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La construcció amb cobertes de làmina metàl·lica autoportant està molt estesa entre la població amb baixos recursos econòmics i tecnològics a causa del seu reduït cost i facilitat d’instal·lació. En latituds amb alta radiació solar directa i difusa, el comportament tèrmic és molt desfavorable a causa de la seva alta transmitància. Crear una coberta de doble fulla amb possibilitat de ventilació pot significar una millora de les condicions de confort interiors. En aquest estudi es defineixen 3 variables de disseny de cobertes ventilades metàl·liques per avaluar-ne el comportament davant la transferència de calor en un clima càlid humit. Les variables estudiades són la separació de les fulles, la inclinació de la coberta i la reflectància de l’acabat superficial exterior. Amb l’objectiu de comparar el comportament tèrmic de les cobertes ventilades, es van mesurar les temperatures superficials i de l’aire en diferents condicions al llarg de 5 mesos, per a això, es van fabricar quatre prototips, un amb coberta simple i tres amb cobertes ventilades, amb la possibilitat de modificar-ne les variables de disseny. Aquestes modificacions van permetre identificar els rangs de configuració que van presentar menors increments de temperatura respecte a la coberta simple de referència. Els resultats obtinguts mostren que una alta reflectivitat del full exterior, una separació més gran de les fulles i un augment de la inclinació de la coberta són factors que permeten disminuir el sobreescalfament per coberta, sent el nivell de reflectància de l'acabat superficial del full exterior el paràmetre amb més impacte., In hot-humid climates, construction of self-supporting metal sheet roofing is widespread among population with low economic and technological resources due to its low cost and ease of installation. In latitudes close to the equator. with high direct and diffuse solar radiation, thermal behavior of metal roofing is very unfavorable because of its high transmittance and the amount of radiation received by the horizontal plane. Duplicating the metal sheet by creating a double sheet roof with the possibility of ventilation can mean an improvement in interior comfort conditions. In this study, 3 design variables of ventilated metal roofs are defined to evaluate their heat transfer behavior in a hot-humid climate. The studied variables are: distance between the metal sheets, roof inclination and reflectance of exterior surface finish. In order to compare the thermal behavior of the ventilated roofs, surface and air temperatures were measured under different conditions over a 5-months period. Hence, four modules were manufactured, one with a single metal sheet roof and three with ventilated cavities, all of them with the possibility of changing the design variables. These modifications allowed to identify the configuration ranges that presented lower temperature records compared with a simple metal sheet roof. Results showed that a high reflectance level of the external foil, a greater distance between the metal sheets and a pronounced roof inclination, are factors that allow reducing roof overheating, in which surface reflectance level of the external sheet was the parameter with the greatest cooling impact., La construcción con cubiertas de lámina metálica auto portante está muy extendida entre la población con bajos recursos económicos y tecnológicos debido a su reducido costo y facilidad de instalación. En latitudes con alta radiación solar directa y difusa, su comportamiento térmico es muy desfavorable debido a su alta transmitancia. Crear una cubierta de doble hoja con posibilidad de ventilación puede significar una mejora de las condiciones de confort interiores. En este estudio se definen 3 variables de diseño de cubiertas ventiladas metálicas para evaluar su comportamiento ante la transferencia de calor en un clima cálido húmedo. Las variables estudiadas son: la separación de las hojas, la inclinación de la cubierta y la reflectancia del acabado superficial exterior. Con el objetivo de comparar el comportamiento térmico de las cubiertas ventiladas, se midieron las temperaturas superficiales y del aire en distintas condiciones a lo largo de 5 meses, para lo cual, se fabricaron cuatro prototipos, uno de ellos con cubierta simple y tres con cubiertas ventiladas, con la posibilidad de modificar sus variables de diseño. Dichas modificaciones permitieron identificar los rangos de configuración que presentaron menores incrementos de temperatura con respecto a la cubierta simple de referencia. Los resultados obtenidos muestran que una alta reflectividad de la hoja exterior, una mayor separación de las hojas y un aumento de la inclinación de la cubierta son factores que permiten disminuir el sobrecalentamiento por cubierta, siendo el nivel de reflectancia del acabado superficial de la hoja exterior el parámetro con mayor impacto., Esta publicación es parte del proyecto de I+D+i PID2020-116036RB-I00, financiado por MCIN/AEI/10.13039/501100011033 y ha contado con el apoyo del Consejo Nacional de Humanidades Ciencias y Tecnologías (CONAHCYT) del Gobierno Mexicano. ACE_52_11811_ESCOBAR_ET_AL, Peer Reviewed

The thermal design of small satellite missions is critical for ensuring the performance and longevity of onboard instruments. This thesis focuses on the thermal design of Foresail-2, a 6U CubeSat mission to Geostationary Transfer Orbit (GTO), specifically addressing the thermal challenges associated with the magnetometer located at the end of a long boom featured on the satellite. The objective of this research is to estimate the orbital loads, study its effects and develop an effective thermal control strategy to maintain the frame, boom and magnetometer temperature within an optimal operational range throughout the mission duration. A steady state thermal analysis is conducted to evaluate the effects of the GTO environment on the satellite structure under different operational scenarios and design conditions. To achieve the desired thermal control, several potential regulation strategies are investigated, including passive thermal coatings, insulation materials, and active cooling methods. Furthermore, thermal simulations are performed to predict the temperature profiles and gradients within the boom and magnetometer assembly, enabling the identification of potential hotspots or areas prone to thermal stress using ANSYS software package. These findings contribute to the implementation of thermal design modifications and the optimization of the configuration of the boom and magnetometer to enhance thermal performance. The results of this thesis contribute to the development of a robust thermal design for Foresail-2 mission satellite. Moreover, the methodologies and insights gained from this research can be extended to other CubeSat missions with similar thermal requirements and constraints.

Present as well as future challenges of space exploration point to the need for improved thermal control systems. The “Effect of Marangoni Convection on Heat Transfer in Phase Change Materials” experiment, which is approved by ESA for execution on board the International Space Station, aims to contribute directly to current knowledge and basic understanding of heat and mass transport in phase change materials (PCMs) that incorporate a free surface in reduced gravity. The experiment will apply fixed temperatures to opposite ends of PCM samples held in cuboidal and cylindrical containers in order to drive controlled melting and solidification cycles that will be observed by means of optical cameras. The recorded images will be complemented by thermal measurements at key positions along the samples, which will allow different thermocapillary flow regimes to be distinguished according to their temporal dynamics. It is anticipated that thermal Marangoni (thermocapillary) convection will increase the heat transfer rate in these PCM devices by a significant factor (on the order of two or more) compared to melting governed by thermal diffusion (conduction). If the PCM designs prove robust, the experiment results can be expected to lead to substantial improvements in future designs for passive PCM applications in space missions.

Spacecraft thermal management is critical for ensuring mission success, as it affects the performance and longevity of onboard systems. A comprehensive overview of the state of the art in spacecraft thermal control solutions, as well as a design methodology framework for efficient and effective thermal management, is provided. Various thermal control solutions, including coatings, insulation, heat pipes, phase-change materials, conductive materials, thermal devices, actively pumped fluid loops, and radiators, are discussed along with the primary sources of heat loading in space. The need for accurate modeling and analysis of the thermal environment to identify appropriate thermal control solutions and design pathways is highlighted. Future innovations in thermal management, such as new materials and technologies that have the potential to further improve the efficiency and effectiveness of thermal control solutions for spacecraft, are explored.

The Deployable Space Telescope (DST) project aims to reduce the stowed volume compared to other Earth observation satellites with a similar resolution. The DST demonstrator functions in the thermal infrared (TIR) domain, which imposes stringent thermal requirements on the detector. The detector must be cooled to 150 K, and the instrument box to 200 K. This thesis documents the lowering of the detector and instrument box temperatures by minimizing the heat input on the detector and the radiators. The addition of a (deployable) Earth shade door minimizes the external heat input on the radiator surfaces. The impact of the satellite's orbit on the thermal environment and the minimum and maximum worst-case scenarios were investigated, which determined that constellation flight was possible. The proposed thermal control system design is fully passive and results in stable detector and instrument box temperatures that meet the set requirements., DST Project, Aerospace Engineering

The traditional single-phase fluid loop (SFL) and traditioanl thermal control algorithm can barely control the temperature rapidly. Thermoelectric cooler (TEC) has been proved to be a good thermal controller because of its high reliability, liquid-free characteristics, and fast response. This paper proposes a TEC-based precooling module that resides in front of the cold plate (CP), and consists of a TEC-CP system, manifesting a high compatibility between the novel precooling module and traditional SFL. The TEC-CP system was designed, and a mathematical model of heat and mass transfer was developed to numerically investigate the effects of the geometric parameters, TEC operating conditions, and liquid cooling states of the precooling module upon payload thermal performance. Through analysis, an optimal TEC-based precooling module with optimal geometric dimensions was attained, where the coolant temperature was decreased by 13.04 K, resulting in a 28.98% reduction compared to that without the precooling module. Transient results also demonstrate that the temperature response time can be within 3 min, indicating a fast response system for temperature control. Results outlined in this paper provide structural and data references for future designs of scientific rack-level thermal control loops in space stations. © 2023 Elsevier Ltd

Present as well as future challenges of space exploration point to the need for improved thermal control systems. The “Effect of Marangoni Convection on Heat Transfer in Phase Change Materials” experiment, which is approved by ESA for execution on board the International Space Station, aims to contribute directly to current knowledge and basic understanding of heat and mass transport in phase change materials (PCMs) that incorporate a free surface in reduced gravity. The experiment will apply fixed temperatures to opposite ends of PCM samples held in cuboidal and cylindrical containers in order to drive controlled melting and solidification cycles that will be observed by means of optical cameras. The recorded images will be complemented by thermal measurements at key positions along the samples, which will allow different thermocapillary flow regimes to be distinguished according to their temporal dynamics. It is anticipated that thermal Marangoni (thermocapillary) convection will increase the heat transfer rate in these PCM devices by a significant factor (on the order of two or more) compared to melting governed by thermal diffusion (conduction). If the PCM designs prove robust, the experiment results can be expected to lead to substantial improvements in future designs for passive PCM applications in space missions.

The latest generation wafer scanners use extreme ultraviolet light to project a pattern of electronic connections onto a silicon wafer. A significant part of the projection light is absorbed by the mirrors in the projection system. This causes the mirrors to heat up and expand, which leads to a significant reduction in the imaging quality of the wafer scanner. The imaging quality can be improved by applying an additional actuation heat load to the mirrors. Because the wafer scanner can be used with a large number of different illumination settings (which lead to different load cases) and the number of thermal actuators is limited, designing an effective actuation heater layout is an important but nontrivial task. To assist this design process, this paper proposes a computational framework to optimize a small number of spatial actuation heat load shapes with their corresponding intensities for a large number of load cases. It is guaranteed that the obtained actuation heat load shapes can keep the steady-state temperature in the optical surface of the mirror sufficiently close to a desired temperature in all considered load cases. The proposed computational framework is applied to a representative three-dimensional finite element model of a mirror. The obtained actuation heat load shapes and their corresponding intensities provide insights for the design of a thermal actuation layout for mirror heating.

This textbook is steered towards higher educational course entailed in Commercial Space Operations. This textbook will be covering in detail Orbital Satellites, and Spacecraft. These topics are discussed according to their application, design, and environment. The power system, shielding and communication systems are reviewed along with their missions, space, environment and limitations. Any vehicle, whether manned or unmanned, intended for space travel is a spacecraft. A spacecraft's required systems and equipment depend on the information it will acquire and the tasks it will perform. Although their levels of sophistication vary widely, they re all subject to the harsh conditions of space. Depending on the missions that each spacecraft is designed to carry out, they can be broadly classed.

Ground thermal tests are always mandatory before any space mission is flown into space. The collected results of these tests are mainly temperatures of the different parts of the spacecraft (nodes) for different mission scenarios. The measured temperatures always show differences with the expected values coming from the computer thermal mathematical models. The origin of these differences is partially related to the inherent error coming from physical measurements. The thermal parameters that compose the computer thermal mathematical models must always be correlated with the results coming from tests. This paper studies, through three thermal models, the difficulties that are found in the correlation process when the measured temperatures reach a certain level of error. Thermal parameters become more difficult to be identified when the measurement error level increases. However, the temperature fields obtained with these poor thermal parameters are good enough for the mission thermal analysis. Several error levels, different load cases and correlation for steady-state and transient cases are studied to probe these findings.

There are always differences between the computer predicted temperatures of a spacecraft thermal model and the temperatures measured during the mandatory laboratory thermal tests. As a consequence, the model must be correlated before the spacecraft is launched to space, in order to identify the correct parameters that match the experimentally measured temperatures. A new technique is presented to identify the parameters, based on the minimization of the error of the transient equations which governs the heat transfer in the spacecraft. The steady state minimization was pre-sented in a previous work, but the transient techniques presented hereafter enable a better and more extended identification of parameters despite the higher complexity of the computational problem. The use of a set of available subroutines (TOLMIN), which permits the constrained optimization of a general function, makes possible to ensure that the obtained parameters are non-negative, a requirement to have physical sense. The gradient function must be calculated for each problem, but this can be done automatically. Results show that for small and medium size transient Thermal Mathematical Models (TMM), a good corre-lation of thermal parameters can be achieved even if some of the nodes temperatures are not measured in the thermal tests.

To achieve the automation of blast furnace operation, an automatic control system for hot metal temperature (HMT) was developed. Nonlinear model predictive control (NMPC) which predicts up to ten-hour-ahead HMT and calculates appropriate control actions of pulverized coal rate (PCR) was constructed. Simulation validation showed that the NMPC algorithm generates control actions similar to those by the operators and that HMT can be maintained within ±10 °C of the set point. The automatic control system using NMPC was then implemented in an actual plant. As a result, the developed control system suppressed the effects of disturbances, such as the changes in the coke ratio and blast volume, and successfully reduced the average control error of HMT by 4.6 °C compared to the conventional manual operation. The developed control system has contributed to the reduction of reducing agent rate (RAR) and CO2 emissions., Control & Simulation

In spite of high solar radiation being an advantage for the performance of solar photovoltaic (PV) panels, the caused high surface temperature of the panel surface reduces their efficiency, as well as lifetime span due to cyclic thermal stresses. PV panels are deteriorating due to two setbacks from a harsh climate: shallow temperatures during the night leading to condensation and overheating during the day leading to reduced efficiency. The present paper discusses and resolves the two setbacks in the PV performance by cooling the panel during the day and heating the panel during the night using water circulation in a ground embedded heat exchanger. Experimental and numerical methods were used to carry out the investigation on the influence of the proposed technique on the PV performance. Following the experiments, a computational model has been developed to simulate the experimental set-up. Two PV modules have been tested simultaneously in outdoor environment; one is bare and the second is integrated with ground heat exchanger. Results revealed that the integrated heat exchanger has managed to reduce the PV surface temperature by around 8oC during the daytime and rise the PV surface temperature by around 3oC more than the due temperature, at which condensation takes place during the night time. The developed technique has proved to be highly efficient as a PV thermal control method.

This thesis is on the subject of how propellant heating considerations affect the design of a CubeSat cold gas propulsion system. Computer simulation tools are used to analyse heat flow through the system, as well as the fluid flow and phase change of butane. The heating performance is presented for different operational states and different designs. Finally, an optimal system design is suggested. The propulsion system in question is the deep space heading Hera Juventas 6DOF CGPS. The Juventas spacecraft will as part of ESA’s Hera mission be the first to perform radar measurements of an asteroid. It will determine the result of the NASA DART mission and will give insights to the internal structure of the Dimorphos minor- planet moon., Detta examensarbete behandlar utformningen av ett CubeSat kallgasframdrivningssystem med avseende på drivmedelsuppvärmning. Datorsimuleringsverktyg används för att analysera värmeflöde genom systemet samt flödet och fasförändringen av butan. Värmningsprestanda presenteras för olika driftstillstånd och olika konstruktioner. Slutligen föreslås en optimal systemdesign. Framdrivningssystemet i fråga är Hera Juventas 6DOF CGPS. Rymdfarkosten Juventas kommer som en del av ESA:s Herauppdrag att vara den första som utför radarmätningar av en asteroid. Den kommer att avgöra resultatet av NASA:s DARTuppdrag och kommer att ge insikter om den interna strukturen i asteroidmånen Dimorphos.

Дана магістерська дисертація складається з вступу, 4 розділів, висновків, списку використаної літератури та додатків. Повний обсяг роботи склав 130 сторінок, містить 64 ілюстрації та 24 таблиці. Опрацьовано 54 джерела літератури. Як результат роботи над магістерською дисертацію було розроблено функціональну схему та оптичній тракт тепловізійної системи з мультиспектральним комплексуванням зображення, розроблено 3 повноцінних програми та навчено нейронну мережу. Також було розроблено стартап-проект, для аналізу можливого комерційного використання розробленої системи. Головною функцією розробленої системи має стати масовий контроль температури тіла людей в місцях скупчень, для виявлення підвищеної температури – головним симптомом інфекційного захворювання. Події останнього року продемонстрували нам актуальність даної проблеми., This master's dissertation consists of an introduction, 4 chapters, conclusions, list of references and appendices. The total volume of the work was 130 pages, contains 64 illustrations and 24 tables. Processed 54 sources of literature. As a result of work on the master's dissertation the functional scheme and optical tract of thermal imaging system with multispectral image fusion were developed, 3 full-fledged programs were designed and the neural network was trained. A startup project was also developed to analyze the possible commercial use of the designed system. The main function of the designed system should be mass control of body temperature of people in places of accumulation, to detect fever - the main symptom of an infectious disease. The events of the last year have shown us the urgency of this problem.

This paper puts forward an approach for boosting the efficiency of energy management strategies (EMSs) in fuel cell hybrid electric vehicles (FCHEVs) using an online systemic management of the fuel cell system (FCS). Unlike other similar works which solely determine the requested current from the FCS, this work capitalizes on simultaneous regulation of current and temperature, which have different dynamic behavior. In this regard, firstly, an online systemic management scheme is developed to guarantee the supply of the requested power from the stack with the highest efficiency. This scheme is based on an updatable 3D map which relates the requested power from the stack to its optimal temperature and current. Secondly, two different EMSs are used to distribute the power between the FCS and battery. The EMSs' constraints are constantly updated by the online model to embrace the stack performance drifts owing to degradation and operating conditions variation. Finally, the effect of integrating the developed online systemic management into the EMSs' design is experimentally scrutinized under two standard driving cycles and indicated that up to 3.7% efficiency enhancement can be reached by employing such a systemic approach. Moreover, FCS health adaptation unawareness can increase the hydrogen consumption up to 6.6%.

Active thermal control is crucial in achieving the required accuracy and throughput in many industrial applications, e.g., in the medical industry, high-power lighting industry, and semiconductor industry. Thermoelectric Modules (TEMs) can be used to both heat and cool, alleviating some of the challenges associated with traditional electric heater based control. However, the dynamic behavior of these modules is non-affine in their inputs and state, complicating their implementation. To facilitate advanced control approaches a high fidelity model is required. In this work an approach is presented that increases the modeling accuracy by incorporating temperature dependent parameters. Using an experimental identification procedure, the parameters are estimated under different operating conditions. The resulting model achieves superior accuracy for a wide range of temperatures, demonstrated using experimental validation measurements.

As the CubeSats have been getting more energy dense over the years, a greater need has come for thermal control on CubeSats. Phase Change Materials (PCMs) are researched in this thesis as an energy dense passive Thermal Storage Device (TSD). This energy density comes from the melting of the PCM. To determine the feasibility of this TSD. The thermal storage device needed to be able to keep certain components from overheating while keeping other components from getting too cold. This thesis successfully tested that the PCM was able to store heat from a radio and use that heat to keep a CubeSat battery warm. The TSD is meant to stabilize the temperature of all components connected to it by maintaining a temperature around the melting temperature of the PCM. Prototypes were made using eicosane wax, it is a paraffin wax with a melting temperature of 36.7∘C. This PCM was chosen due to its safe and predictable properties, and because of its previous use in the space industry. Two different casings where tested with two different filler materials and casing sealing methods. Although the filler materials had a relatively small effect on the thermal response of the casing at the heat fluxes tested. The fin filler material used less mass and was simpler to manufacture than the honeycomb filler. There was a large difference in the sealing method of the casing that was glued together sealed better than the one laser welded together, the casing which had fill ports that were clamped with a thread with a rubber filament O-ring between them sealed better than the one that was glued on. Although the degree to which this could be tested was limited and is therefore difficult to draw definitive conclusions over. The tests proved that the TSD was much more effective than traditional heat sinks at storing heat. This will allow energy dense CubeSats with large intermittent heat-loads to be designed for their average temperatures and not for extreme peaks and valleys. The complexity this, Aerospace Engineering

The Deployable Space Telescope (DST) project aims at producing a competitive telescope by using segmented deployable light weighted optics which reduces launch volume and mass, and thus launch costs. Due to the criticality of heat management to the performance of the telescope, a thermal model had to be built in order to determine the expected temperatures throughout the telescope in orbit. Further, the premature baffle design required a supportive thermal analysis such that its critical parameters could be determined., Aerospace Engineering

The purpose of the thesis was to design a deployable thermal shielding baffle for the Deployable Space Telescope to reduce thermal gradients on the optical elements. As a result of a trade-off, the deployment was chosen to be based on an inflatable structure. The baffle consists of aluminium-kapton booms that form a cylindrical shape, and are rigidised after deployment through overpressurisation. Thermal shielding is provided by a blanket of multi-layer insulation surrounding the cylinder. Numerical analysis has shown that the baffle can withstand expected static and vibrational loads during operations, and preliminary thermal analysis results show that temperatures on the telescope are stabilised., Deployable Space Telescope, Aerospace Engineering | Astrodynamics & Space Missions

With the ever-increasing laser power and repetition rate, thermal control of laser media is becoming increasingly important. Except for widely used air cooling or a bonded heat sink, water cooling of a laser medium is more effective in removing waste heat. However, how to protect deliquescent laser media from water erosion is a challenging issue. Here, novel waterproof coatings were proposed to shield Nd:Glass from water erosion. After clarifying the dependence of the waterproof property of single layers on their microstructures and pore characteristics, nanocomposites that dope SiO 2 in HfO 2 were synthesized using an ion-assisted co-evaporation process to solve the issue of a lack of a high-index material that simultaneously has a dense amorphous microstructure and wide bandgap. Hf 0.7 Si 0.3 O 2 /SiO 2 multifunctional coatings were finally shown to possess an excellent waterproof property, high laser-induced damage threshold (LIDT) and good spectral performance, which can be used as the enabling components for thermal control in high-power laser cavities.

At present, an urgent task is to reduce errors in non-contact thermal control. The article suggests a model of an extended infrared emitter as a working tool for calibration with thermal control of copper surfaces. The emitter is made of double-sided foil-coated glass-textolite measuring 5x5 cm. The heating element is made in the form of a conductive path. The calculated thermogram of the theoretical model of the emitter, made in the program ANSYS Workbench, is presented. During the simulation, a necessary and sufficient number of heating zones and their size are determined. A structural diagram of the automatic temperature control system for the emitter has been developed. Experimental data were obtained during the experiment: the temperature distribution of the real model of the infrared emitter and the quality of the PID regulator regulation. The real and theoretical models of the emitter are compared. The unevenness of the temperature distribution on the surface in both cases was not more than 1 K., В настоящее время актуальной задачей является уменьшение погрешностей при бесконтактном тепловом контроле. В статье предложена модель протяженного инфракрасного излучателя как рабочего средства калибровки при тепловом контроле поверхностей из меди. Излучатель выполнен из двустороннего фольгированного стеклотекстолита размером 5x5 см. Нагревательный элемент выполнен в виде токопроводящей дорожки. Представлена расчетная термограмма теоретической модели излучателя, выполненная в программе ANSYS Workbench. В ходе моделирования определено необходимое и достаточное количество зон нагрева и их размер. Разработана структурная схема системы автоматического регулирования температуры для излучателя. В ходе эксперимента получены опытные данные: распределение температуры реальной модели инфракрасного излучателя и качество регулирования ПИД-регулятора. Произведено сравнение реальной и теоретической моделей излучателя. Неравномерность распределения температуры на поверхности в том и другом случае составила не более 1 K.

In the article, there was considered the reliability of the operation of high-temperature aggregates in the context of the reliability of the operation of its lining. The determination of the reliability of the thermal operation of the lining and prediction of its further operation without exceeding the operational limits is carried out in various ways. The specificity of the lining of high-temperature units limits the application of methods of thermal control of their operation. Thus, the authors of the article proposed for these purposes a method for determining the thermal state of the lining of a high-temperature aggregate, which allows to determine with sufficient accuracy the temperature fields in the lining of a high-temperature aggregate with minimal disruption of the lining integrity. Its use in laboratory conditions showed its sufficient accuracy and simplicity. In order to determine the reliability of high-temperature units, there were determined the most significant factors affecting the service life. These are the values of the temperature stresses (both compression and expansion) that exceed the permissible values; the point of transition from the compression zone to the zone of action of the tensile forces and the duration of the action of the critical stresses (that is, the stresses exceeding the permissible level for the given material). Further, a criterion was developed for evaluating the reliability of the lining operation, which includes the three factors listed above, and a procedure was developed to determine this factor for the lining of high-temperature units during their operation. The reliability criterion is the total index for all the time points of the thermal operation of a high-temperature aggregate, under which the temperature stresses exceed the ultimate strength. The procedure involves determining the thermal state of the lining according to the developed method and calculating the reliability criterion. Taking into account the sta, В статье рассмотрена надёжность работы высокотемпературных агрегатов в рамках надёжности работы его футеровки. Определение надёжности тепловой работы футеровки и прогнозирование её дальнейшей работы без допущения превышения эксплуатационных пределов, осуществляется различными способами. Специфика эксплуатации футеровок высокотемпературных агрегатов ограничивает применение способов теплового контроля их работы. Авторами статьи для этих целей предложен способ определения теплового состояния футеровки высокотемпературного агрегата, который позволяет с достаточной точностью определять температурные поля в футеровки высокотемпературного агрегата с минимальным нарушением целостности футеровки. Его применение в лабораторных условиях показало его достаточную точность и простоту. Для определения надёжности работы высокотемпературных агрегатов были определены наиболее значимые факторы, влияющие на продолжительность эксплуатации. Это – значения величин температурных напряжений (как сжатия, так и растяжения), превышающих допустимые; точка перехода из зоны сжатия в зону действия растягивающих усилий и продолжительность действия критических напряжений (то есть напряжений, превышающих допустимый уровень для данного материала). Далее были разработан критерий для оценки надёжности работы футеровки, включающий три вышеперечисленных фактора, а также создана методика по определению данного фактора для футеровки высокотемпературных агрегатов при их эксплуатации. Критерий надёжности является суммарным показателем для всех моментов времени тепловой работы высокотемпературного агрегата, при которых температурные напряжения превышают предел прочности. Методика включает определение теплового состояния футеровки по разработанному способу и вычисление критерия надёжности. С учётом статистики по выводу высокотемпературных агрегатов в ремонт по неудовлетворительному состоянию футеровки производится определение минимально допустимых критериев для оценки надёжности работы футеровки, при достижении

An active fluid heat exchanger can be controlled effectively using Peltier elements to condition the temperature of the fluid flowing through the heat exchanger. The thermal resistance of the heat exchanger can be reduced to increase the speed of controlling the fluid's temperature. Topology optimization is used in this study to find the geometry of a heat exchanger with reduced thermal resistance. The design of a heat exchanger using topology optimization requires the coupling of the fluid flow equations and the energy equation in a finite element model with a continuous design variable. The existing optimization models perform well when the goal of the optimization problem is to minimize viscous dissipation. A weighted sum multi-objective function is however necessary to optimize the thermal performance of a design, and the correct choice of weights to meet design specifications is difficult to arrive at. The drawback in the existing model is that the conductivity distribution is defined as a function of the design variable of the optimization problem. This results in infeasible designs when the goal of the optimization problem is to minimize only thermal resistance, and this is demonstrated with several numerical examples along with a motivation for a new formulation. A new formulation for conductivity distribution is proposed in this thesis. The new formulation defines the conductivity distribution in terms of the velocity field in the design domain. The new formulation is capable of significantly reducing the thermal resistance of the heat exchanger, and this is demonstrated with a numerical example. Finally, a 3d design case is implemented, the results of the optimization routine are post-processed and the performance of the baseline design from ASML is compared with the topology optimized design., Mechanical Engineering

Two-phase thermal control systems are used for payloads that require temperature stability under high and fluctuating heat output. However, the complex interaction between the two phases in a flow makes it hard to predict the performance of such a system. The goal was to develop a numerical model able to predict the transient behaviour of such a system within a 30% error margin. An existing explicit one-dimensional finite-difference simulation was expanded using new correlations from literature. The performance of this model was validated using experimental measurements gathered with the NLR two-phase demonstrator setup. The resulting numerical simulation can predict the transient behaviour of the pressure drop and liquid level in the accumulator with a mean error of 7.7% and 1.3% respectively. The goal therefore has been reached.While room remains for further improvement and validation, this model can significantly shorten the development time of new two-phase systems., Aerospace Engineering

This document contains the design of a solar sail. Three main parts will be studied in this project: structural design, thermal design and deployment . The first one will be based in studying the different materials that can be used nowadays to build a solar sail, they will be compared and finally, one will be chosen. The loads on the sail will be also evaluated and the place of all the components too ; the components that will be on the film and the ones that will be placed on the main structure, always taking into account the different interactions that will exist between them and the assembly requirements. The second one will study the thermal equili brium. This equilibrium is based on computing not only the temperature reached on the film, also th e temperature reached at all those components exposed to the Sun. Once the result will be found, some changes will be done in order to accomplish the functio nal requirements listed by the mentioned components. On the other hand, the different types of deployment will be evaluated an compared. Finally one of them will be selected according to the characteristics that our project needs. At the same time, this deployment mechanism will add more components that will be studied in the first chapter. The final result will be a solar sail that, even though the efforts made to reduce the global mass, is heavier than 100 grams so, the conclusion will be that nowadays it is impossible to build this kind of spacecraft. However, the possibility of a solar sail completely func t ional , spending long time periods in mission (analyzing the magnetic camp) will be ratified . The project will end with a built and deployed sola r sail which will be composed for a thin film of Mylar (at 44ºC) with two coatings; one of aluminum and the other of chromium. The deployment system that is going to be chosen is the one that uses the inertia of the Booms to deploy the sail, avoiding any k ind of extreme loads

Numerous species in Family Dermestidae (Coleoptera) are important economic pests of stored goods of animal and vegetal origin, and museum specimens. Reliance on chemical methods for of control has led to the development of pesticide resistance and contamination of treated products with insecticide residues. To assess its practicality as an alternate method of control, we review the literature on the tolerance of dermestids to extreme hot and cold temperatures. The information for dermestid beetles on temperature tolerance is fragmentary, experimental methods are not standardized across studies, and most studies do not consider the role of acclimation and diapause. Difficulties in determining the diapause status of dermestid larvae may explain the lack of studies. The few studies that do examine these factors show that they can greatly increase tolerance to cold temperatures. The use of extreme temperatures will need to target the most tolerant life stage, which for dermestids at cold temperatures will potentially be the cold-acclimated individuals in diapause. The development of effective protocols will be facilitated by studies that clearly and completely describe experimental and statistical methods, consider factors (life-stage, acclimation, diapause) that increase tolerance to extreme temperatures, and assess the mortality at various temperatures to develop mathematical models.

Modern office buildings commonly have fully glazed façades in order to reflect a luxurious appearance while maximizing the daylight penetration to the interior space. Though glass façades provide plentiful natural light, the amount of energy needed to maintain indoor thermal comfort poses a great challenge to the designers with the cost of what is called environmental services (those services devised to control the internal thermal and ventilation environment) to be respectively high. The effect of responsive building fabrics to complement, reduce and in some cases render unnecessary, mechanical and electrical environmental systems, may result in effective redeployment of a building’s construction and maintenance budget. In the same time, it can increase occupant comfort and control. The “Water Wall” is an experimental system which was designed to explore the potentials of water as a construction material to regulate the exchange of energy between a building and its environment. The concept originates from research done on the field of biomimetics and inspiration gained by the way living organisms maintain their body’s temperature within comfort limits; it is motivated by the thought that the challenge of having a constant interior environment while the temperature and the weather outside fluctuate has been tackled many times in nature and this could provide inspirational solutions to the design process. The idea of introducing variability into the fabric of a building to respond to changes, rather than relying on building services, offers tremendous advantages; it actually extends the ideas and principles already well-established in building and accords with the propositions of Darwin, who held that the capacity to survive depends on the ability to adapt to a changing environment. All in all, “Water Wall” is an easy to install modular frame system that controls the heat energy flow by the use of variable thermal mass (water) and the direct solar heat gain through a, Architecture and The Built Environment, Architectural Engineering +Technology, Building Technology

The CubeSat platform has long since its introduction surpassed its original intend of being an educational and technology demonstration platform only. The recognition and acknowledgement of its potential has led to an everlasting hunger for more performance, which translates directly into a demand for more power. The power density of CubeSats is rapidly increasing leading to thermal hotspots that can be destructive for any CubeSat mission. The solution proposed to cope with this increase in power density is the water heat pipe: A two-phase, passive thermal control device that is able to transport a large amount of heat without introducing a large thermal gradient over the heat source and sink. For CubeSat application performance characterization tests have been carried out including investigation on its behaviour when bent, tilted against gravity, and frozen. Tests were carried out with commercial copper heat pipes with a diameter of 6mm and 200mm in length (fitting the CubeSat’s structural dimensions) for three different wick structures; axial grooved, mesh, and sintered. The results showed that the axial grooved and sintered heat pipes were easily capable of transporting more than the expected heat loads (10W OAP) for nextgeneration CubeSats without introducing large thermal gradients between heat source and sink. The performance of heat pipes is characterized by an increase in heat transfer coefficient for higher heat pipe temperatures, while at temperatures below the freezing point of water only pure copper conduction remains. Successful start-up from the frozen state was accomplished while repetitive freeze/thaw cycling showed no internal or external damage. Finally, CubeSat integration tests showed that the heat pipe was able to achieve ?T reduction of 45.6°C for a heat load of 3W. It also proved to be successful in removing a continuous 10W heat input, while keeping the PCB chip temperature within limits. The critical aspect in integrating a heat pipe in the, Aerospace Engineering, Space Engineering

The increasing power consumption of integrated circuits (ICs) enabled by technology scaling requires more efficient heat dissipation solutions to improve overall chip reliability and reduce hotspots. Rapidly growing 3-D IC technology strengthens the requirement with more devices stacked per unit area. Thermal interface material (TIM) and MicroChannel are widely adopted strategies to resolve the heat dissipation problem. In recent years, carbon nanotubes (CNTs) have been proposed as a promising TIM due to their superior thermal conductivity. Several CNT-based thermal structures for improving chip heat dissipation have been proposed and demonstrated significant temperature reduction. In this project, we developed an improved CNT TIM structure which includes a CNT grid and thermal vias. It collaborates with MicroChannel to dissipate heat more efficiently in 3-D chips and at the same time, obtain more uniform chip thermal profiles. We present simulation-based experimental results that indicate up to 19.88% peak temperature reduction, 7.81% average temperature reduction, over 66% maximum temperature difference reduction on chip and 17.26% improvement in chip reliability for IBM-PLACE 2.0 circuit benchmarks, showing the effectiveness of our proposed thermal structure for resolving thermal challenge and improving chip reliability in 3-D IC.

The session included presentations on approaching space development as a newcomer, which were obviously different from the approach taken by existing large industries in the space field. It was pointed out that one of space development technologies developed by an industrial corporation was systems integration. NASA adopted the management methods for research and development used by the US military. These methods were accepted subsequently by engineering corporations in the US. In Japan they were said to be accepted first by engineering corporations rather than by space development agencies. In addition, the utilization of lunar resources and the technology of looped capillary heat pipes in thermal control were discussed. Another topic was the TARA Center (Center for Tsukuba Advanced Research Alliance) of the University of Tsukuba, in which a rolling tenure system, the abolition of the retirement system, and the heavy emphasis on the outside evaluation system were adopted., 本セッションで、新参者として宇宙開発に参加することについての発表があった。これは宇宙分野に経験のある大企業によって取られるアプローチとは当然違っていた。技術系企業によって採用された宇宙開発技術の1つはシステム統合であると指摘された。NASAは米国軍隊によって使用されている研究開発の管理方法を採用した。この方法はその後米国の技術系企業によって採用された。日本では、この方法がはじめに宇宙開発事業組織にではなく、技術系企業によって採用されたと言われている。また、月資源の利用および熱制御におけるループ状毛細管熱パイプの技術も議論された。もう1つのトピックスとして、筑波大学TARAセンター(先端学際領域研究センター)で、回転テニュア制、定年制の廃止、外部評価の強調が採用されているとの報告があった。

Usable computers for small scaled landing experimental vehicle, the usability of small-sized computer on the market, and the fundamental structure of onboard computer system were investigated. It became clear that the system construction by the utilization of small-sized computer on the market was difficult due to the necessity of substantial improvement for interface circuit, mechanical reinforcement, and thermal control. This report concluded that the procedure such as procurement of Central Processing Unit (CPU) board or manufacturing of CPU from chip, and furthermore the manufacturing of special interface circuit was essential to construct the small-sized onboard computer for landing experimental vehicle., 小型着陸実験機に使用できる可能性のある計算機の調査、市販小型計算機の使用可能性の検討、および搭載計算機システムの基本的構成の検討を行った。その結果、インターフェース回路の大幅な改修の必要性と機械的補強および熱的制御の必要性により、市販の小型計算機を流用しシステムを構築することは困難であり、CPUボードレベルを調達するかチップレベルからCPUを製作し、さらに専用インターフェース回路を制作することにより、小型着陸実験用搭載計算機を構築する必要があるという結論が得られた。

This study reports the system concept of a lunar rover, an unmanned vehicle to explore the lunar surface. The lunar rover missions were defined as precursor missions for future lunar resource utilization and lunar activities. They include resource exploration, environment observations, terrain observation, ground survey, and resource utilization experiment. Various mission scenarios were suggested based on the expected requirements of the lunar missions. Various options for the possible configurations of the lunar rover systems were proposed. The operation concept of the lunar rover was studied, where types of daytime and nighttime operations was considered. The power requirements to satisfy these operating conditions were discussed and the necessary power supply system was investigated. One of the lunar environmental characteristics which may affect the rover system is the regolith. The effects of the regolith deposit on the rover and its surface equipment were discussed and evaluated. Among the problems are the increase in the radiater temperature and associated degradation of the radiation ability, and the degradation of the solar cell performance. However, the regolith coverage increases insulation, and therefore it was considered to give no adverse effect on the nighttime operations. The considerations in the design to cope with the problems were discussed. The critical technology for the thermal control during the rover driving was investigated. A method to attach phase change materials to the exterior of the motor housing to prevent heat build-up was investigated and tests performed. It was shown that the temperature difference between the motor section and the phase change materials was only a few degrees Celsius. The use of the phase change materials was proved to be effective in preventing the motor heat build-up., 本研究は月面探査を目的とした無人の月面車のシステム概念について報告した。月面車計画を将来の月資源の有効利用および月面活動の予備段階として定義づけた。月面活動には資源の開発、環境観察、地表調査、および資源活用実験を含む。月面車計画が満たすべき目標の検討に基づいて種々の計画のシナリオを提案した。月面車システムの構成について検討し、種々の可能性について考察した。昼間および夜間の月面車操作について検討した。その場合の電力消費量を想定し、電力の供給システムについて考察した。月面車システムに影響を及ぼす月の環境特性の1つは表層土の問題である。月面車とその装備への表層土沈着の影響について検討した。放射板の表面温度の上昇とそれに伴う影響、および太陽電池の性能の劣化が問題となる。この問題を解決するための設計上の配慮を研究した。しかしながら、表層土による月面車の被覆は絶縁効果を増大させ、夜間の操作には不利にはならない。月面車の運転中における熱制御の重要な技術を研究した。モータ格納箱の外側に相変化物質を着装して熱蓄積を防止する技術を研究し、実験を行なった。この結果、モータ部分と相変化物質間の温度差はわずか摂氏数度であった。この材料の使用がモータの過熱防止に効果的であることを証明した。

Implementación de un interferómetro láser homodino de fase modulada., [ANGLÈS] Gravitational waves were predicted by Albert Einstein as a direct implication of the theory of General Relativity (1915). Although there are compelling experimental evidences of its existence, its detection has not been possible to the date. LISA (Laser interferometer Space Antenna) mission and its precursor mission LISA Pathfinder were designed as a complementary to terrestrial detectors, like LIGO and VIRGO, in order to obtain direct detection of gravitational waves at the frequency range of 100 μHz < f < 0.1 Hz. In this spectral range, the Universe is rich in gravitational waves sources and the sensitivity of terrestrial detectors is severely degraded. This project describes an implementation of homodyne deep phase modulation interferometer in the context of the space mission LISA, which aims to detect gravitational waves through laser interferometry. In order to do so, a laser diode control has been developed, besides an optical bench where the interferometer is implemented. This interferometric technique is based in a pathlength phase modulation of one interferometer arm with a sinusoidal modulation signal. When the interference is obtained, an algorithm, designed as an extension of the ""J1 … J4" method is applied in order to extract the phase value from the interfered signal. This technique has been proposed like an alternative to heterodyne interferometry to be used in some subsystems of the LISA mission due to the ability to achieve similar performances transferring complexity from optics to electronics. The study represents a starting point for future implementation of a test bench with a stable environment to develop a deep phase modulation interferometer operative with picometer sensitivity at the desired frequency range. This sensitivity value is the minimum required by LISA mission to detect gravitational waves in the space., [CASTELLÀ] Las ondas gravitacionales fueron predichas por Albert Einstein como una consecuencia de la Teoría de la Relatividad General (1915) y a pesar de que se han obtenido evidencias experimentales de su existencia, hasta el día de hoy no se ha logrado su detección. La misión LISA (Laser Interferometer Space Antenna) y su misión precursora LISA Pathfinder, se proponen como complemento a los detectores terrestres, tales como LIGO y VIRGO, para conseguir detectar ondas gravitacionales en el rango de frecuencias entre 100 μHz < f < 0.1 Hz. En esta región del espectro, el Universo es rico en fuentes de ondas gravitacionales y los detectores terrestres ven su sensibilidad gravemente disminuida. El presente proyecto describe la implementación de un interferómetro homodino de fase modulada en el contexto de la misión espacial LISA cuyo objetivo consiste en detectar ondas gravitacionales en el espacio mediante interferometría láser. Para obtener el interferómetro se diseña e implementa la electrónica de control necesaria para el correcto funcionamiento del láser, además del banco óptico donde se situará el interferómetro. La técnica de interferometría utilizada tiene como principio la modulación del camino óptico mediante una señal sinusoidal portadora. Una vez obtenida la interferencia, para poder extraer el valor de la fase de la señal modulada se utiliza un algoritmo que consiste en una extensión del método conocido como "J1 … J4". La implementación de esta técnica ha sido propuesta como alternativa al uso de la interferometría heterodina en subsistemas en la misión LISA debido a que es posible conseguir prestaciones similares trasladando la complejidad del nivel óptico al electrónico. Este estudio sirve como punto de partida para la futura implementación de un banco de pruebas que contenga las condiciones necesarias para obtener un interferómetro de fase modulada operativo con una sensibilidad del orden de picómetros en el rango de frecuencias de interés comentado. E, [CATALÀ] Les ones gravitatòries van ser predites per Albert Einstein com a una conseqüència de la Teoria de la Relativitat General (1915) i encara que s’han obtingut evidències experimentals de la seva existència, fins avui en dia, no s’ha aconseguit la seva detecció. La missió LISA (Laser Interferometer Space Antenna) i la seva missió precursora LISA Pathfinder, es proposen com a complementaris als detectors terrestres, com LIGO i VIRGO, per aconseguir detectar ones gravitatòries al rang de freqüències entre 100 μHz < f < 0.1 Hz. En aquesta regió de l’espectre, l’Univers és ric en fonts d’ones gravitatòries i els detectors terrestres veuen la seva sensibilitat greument empitjorada. El present projecte descriu la implementació d’un interferòmetre homodí de fase modulada en el context de la missió espacial LISA, l’objectiu de la qual consisteix en detectar ones gravitatòries a l’espai mitjançant interferometria làser. Per obtenir l’interferòmetre es dissenya i s’implementa l’electrònica de control necessària per al correcte funcionament del làser, a més del banc òptic on es situarà l’interferòmetre. La tècnica d’interferometria utilitzada té com a principi de funcionament la modulació del camí òptic mitjançant una senyal portadora sinusoïdal. Un cop obtinguda la interferència per extreure el valor de la fase del senyal modulat, s’utilitza un algoritme que consisteix en una extensió del mètode conegut com a "J1 … J4". La implementació d’aquesta tècnica ha estat proposada com alternativa al ús de la interferometria heterodina en subsistemes a la missió LISA degut a que és possible, aconseguir prestacions similars traslladant la complexitat del nivell òptic a l’electrònic. Aquest estudi serveix com a punt de partida per la futura implementació d’un banc de probes que contingui les condicions necessàries per obtenir un interferòmetre de fase modulada operatiu amb una sensibilitat de l’orde de picòmetres al rang de freqüències d’interès esmentat. Aquest valor de sensibili

We present a Stochastic Model Predictive Control (SMPC) algorithm that maintains predefined comfort levels in building Heating, Ventilation and Air Conditioning (HVAC) systems while minimizing the overall energy use. The strategy uses the knowledge of the statistics of the building occupancy and ambient conditions forecasts errors and determines the optimal control inputs by solving a scenario-based stochastic optimization problem. Peculiarities of this strategy are that it does not make assumptions on the distribution of the uncertain variables, and that it allows dynamical learning of these statistics from true data through the use of copulas, i.e., opportune probabilistic description of random vectors. The scheme, investigated on a prototypical student laboratory, shows good performance and computational tractability., QC 20140131

The appropriate choice of the type of glazing and glazed area in a façade depends on many factors. They include amongst other criteria: location, orientation, climatic condition, energetic efficiency, usage of the building, required user comfort, and the architectural concept. All requirements cannot be fulfilled at all times and priorities have to be set to find a compromise between occupant comfort, design objective, cost and energetic efficiency. An innovative glazing system combining daylighting, glare protection, seasonal thermal control and clear view was developed [1] and patented by the authors. This design was developed using a novel ray tracing approach to obtain a strongly angular dependent transmission with specific angular distribution. Taking advantage of the changing elevation of the sun between seasons, a seasonal variation is created by a strongly angular dependent transmittance. In this paper we present the mixed dimensionality approach used to achieve a very fast and accurate ray tracing of any lamellar structure that has a two dimensional profile. The originality of the presented Monte Carlo algorithm is the separation of intersection and interaction. Intersections are computed using only the two dimensions of the profile thereby increasing significantly computational speed. Interactions are computed using vector calculus in three dimensions and provide accurate results with very little computational load. With such optimizations, the user interface could be designed to give an instantaneous idea of the light path in the modelled system. The model also calculates an accurate bidirectional transmittance distribution function that is used in a Radiance simulation to obtain a rendering of the daylighting distribution in an office space. Hereby we can compare the daylighting performances of the novel design based on optical microstructures with those of other CFSs. Finally the combination of simulated angular dependent transmittance and Meteonorm dat

Severe thermal conditions can exist within ground combat vehicles; although these vehicles are generally equipped with heating, ventilation, and cooling (HVAC) systems, the HVAC systems often lack sufficient cooling capacity under conditions of thermally severe weather, open-hatch operations, and significant amounts of on-board electronics., Submitted to 2012 NDIA Ground Vehicle Systems Engineering and Technology Symposium, August 14-16, Troy, Michigan.

RIVM rapport:De groei van legionellabacteriën in een drinkwaterinstallatie kan met uiteenlopende technieken worden beperkt. Zo kunnen drinkwaterleidingen die weinig worden gebruikt regelmatig worden doorgespoeld (thermisch beheer). Een ander voorbeeld is het gebruik van filters in douchekoppen (fysisch beheer). Daarnaast bestaat de zogeheten koper/zilver-ionisatie, waarbij koper- en zilverionen door de leidingen worden geleid (elektrochemisch beheer). Ook kan chloor aan het leidingwater worden toegevoegd (chemisch beheer). Sommige technieken kunnen problemen geven bij de uitvoering ervan. Vooral bij thermisch beheer moeten handelingen vaak worden herhaald en gecontroleerd. Dit gebeurt in de praktijk niet altijd, wat de effectiviteit kan beïnvloeden. Ook bij andere beheerstechnieken is de effectiviteit afhankelijk van een continue uitvoering, controle en onderhoud op de locatie. Dit blijkt uit een onderzoek van het RIVM. Hierin zijn alle bestaande technieken geïnventariseerd en zijn wetenschappelijke bevindingen over de effectiviteit van beheerstechnieken op een rij gezet. Daarnaast zijn enkele partijen in Nederland ondervraagd die te maken hebben met het toetsen of uitvoeren van legionellabeheer. De studie is uitgevoerd in opdracht van de Inspectie Leefomgeving en Transport (ILT, voorheen VROM-Inspectie)., Growth of Legionella in water supply systems can be controlled by several measures. Water pipes can be flushed regularly (thermal control). Another example of a control method is the use of filters on faucets where aerosolisation takes place (physical control). Copper-silver ionization is a method in which copper and silver ions are passed through pipes (electrochemical control). Also chlorine can be added to the water (chemical control). Some control measures can lead to problems in the execution. Especially for thermal control many actions have to be performed and checked regularly. This is not always performed correctly what can affect the effectiveness of the control method. Also for other control methods correct implementation, control and maintenance are important. This is concluded from a study that was conducted by the RIVM. Existing control methods were taken into account and scientific studies on the effectiveness with respect to control of Legionella were investigated. Also, several parties in The Netherlands, involved in the inspection or execution of control measures for Legionella, were interviewed. The study was conducted by order of the "Inspectie Leefomgeving en Transport (ILT)".

In this final report we provide a detailed account of how to call the subroutines of the Mutation library in the context of a practical computational fluid dynamics (CFD) application. The subroutines which were documented in the previous report are shown how to be called in a detailed, step-by-step fashion, from computation of the thermodynamic properties to the transport properties. Specific emphasis is given to integrating the Mutation library with external CFD solvers provided by the user. This is accomplished by providing detailed source code which shows exactly how the library subroutines are to be called. The source code is fully-functioning and may serve as a template for users to build their solvers around that will enable researchers working with the Mutation library to integrate their applications with ease. The subroutines and example code herein, provided in three different computing languages, are a direct implementation of the theory discussed in the second report. Every attempt has been made to use consistent nomenclature and notation, so that the code provided here can be easily compared with the theoretical description., EOARD grant no. 08-3070.

An adaptive resource management system combined with a thermal controller is presented. The aim of the system is to dynamically allocate computing resources to applications competing for the same computing resources in such a way that the system is not overheated. The approach has been implemented on a mobile robot. Experimental results are presented showing the feasibility of the approach.

This design document describes the current status of the Cathode/Anode Satellite Thruster for Orbital Repositioning (CASTOR), which is at the Critical Design Level. The mission of CASTOR is to validate the performance and application of Diverging Cusped Field Thruster (DCFT) technology. The mission will be achieved by taking on-orbit state data to compare the degradation experienced by the DCFT to that of similar technologies. Specifically, the mission objects, with corresponding minimum success criteria are shown below: *Operate the DCFT on orbit for 1500 hours, which is comparable to similar technologies *Minimum Success: Demonstrate that the DCFT will operate on-orbit *Measure the on-orbit performance, efficiency, and degradation of the DCFT during orbital maneuvers *Minimum Success: Use the DCFT to provide a measurable change in velocity, The original document contains color images.

The objective of this work is to develop the capability of testing and characterization of ablative materials exposed to high enthalpy plasma flows including both classical and spectroscopic based measurement techniques. Two different ablative material specimens, a newly developed carbon resin composite ablator (MONA, Lockheed Martin) and a cork compound (AMORIM Cork composites), were selected to perform the measurements. A comprehensive setup of measurement techniques was applied to the Plasmatron facility (chapter 3) to determine and characterize temperature evolution inside and at the surface of the sample as well as the recession rate. Further, the chemical composition of the freestream and the surrounding gas layer in front of the sample during the ablation process was determined using emission spectroscopy. The obtained results are presented in chapter 5, which depicts the degradation of the samples due to ablation (mass loss & surface recession), different temperature measurements (surface & inside) and spectroscopic results (freestream & ablation). A final conclusion of the whole test campaign is made in chapter 6 summarizing the results obtained., EOARD grant no. 08-3069. The original document contains color images.

Turbine blades with controlled textures such as directionally solidified and single crystal structures have proven to have much improved ductility and longer thermal and fatigue life. It has been further reported that the benefits of single-crystal over conventionally cast as well as directionally solidified components critically depend on avoiding the introduction of defects, such as stray grains, freckles, or deviations from the required crystal orientation. Laser-based direct metal deposition (DMD) process equipped with proper sensors and NC devices helps in overcoming those hurdles to fabricate the blades with controlled texture. It appears that thermal control to provide uniform heat flow as well as spatial control of crystal texture by process feedback control is essential. The paper discusses about how to establish process conditions and thermal control requirements, development of a laboratory scale DMD process for spatial control of crystal texture, and mechanical properties of texture-controlled Ni-based superalloy turbine blade components., See also ADM002300. Presented at the Minerals, Metals and Materials Annual Meeting and Exhibition (138th) (TMS 2009) held in San Francisco, CA on 15-19 Feb 2009. Sponsored in part by the Navy. U.S. Government or Federal Purpose Rights. The original document contains color images. Published in Supplemental Proceedings: Volume 1: Fabrication, Materials, Processing and Properties, p405-412, 2009.

This report results from a contract tasking Angstrom Aerospace Corporation as follows: This proposal offers to investigate in greater detail the properties between liquid metals and phase-change materials in nano-micro scale volumes on a fundamental level. Investigations of novel metal-alloy combinations and phase-change materials will be performed through three proposed phases, where the phases go from fundamental research to an experimental device. Properties of such as wetting, adhesion, surface deformation, tension, diffusion, in-stability (mixing) in the boundary interface will be studied. The research will focus on the properties between liquid metal-phase change materials where the melting point of the metal is below the phase change material. A common feature of long hydrocarbon chains (Paraffin and similar) is the distinct volume increase during the phase change from solid to liquid, 15% or more is not unusual. The volume expansion is hydraulic or incompressible to its nature. The metals to be tested are Low Melting Point alloys based on Bismuth/Tin/Indium compositions, but other alloys and even pure metals such as Mercury could beconsidered. The wetting properties between a thin-film of solid metal and the boundary layer created between the LMP and the phase change material will also be investigated., The original document contains color images.

This paper aims at assessing the importance of sorption processes in space applications and the necessity of intelligent control systems for sorption processes. Thermal control and life support systems use extensively sorption processes, taking advantage of their intrinsic stability, their lack of vibrations and their regenerability. ESA's Darwin and Herschel missions' use of sorption cryocoolers is presented. Several life support subsystems employed on ISS are reviewed. A ground based adsorption chiller developed at Shanghai Jiao Tong University is described along with its nonlinear mathematical model. Based on this, a control system that will provide intelligent switching between the dierent operation phases of the chiller is designed. A Java software model of the chiller is used as an internal state estimator and as a source of information for a fuzzy inference module., Validerat; 20101217 (root)

The purpose of this final report is to provide a summary of the University Nanosat 4 Program's AggieSatI. Nanosat 4 was a joint program among AFOSR, AIAA, NASA GSFC, and AFRL/VS. The objectives of the program were to educate and train the future workforce through a national student satellite design and fabrication competition, and to enable small satellite R&D, payload development, integration, and flight test. Nanosat 4 had two distinct stages. The first part was a design and build phase involving 11 Universities, which lasted two years and culminated in the AIAA Student Satellite Flight Competition in March 2007. The competition winner was to be integrated with the AFRL Internal Cargo Unit (ICU) for flight on the Space Shuttle. The second part consists of construction and test of the flight unit and culminates in launch of the Nanosat. The selected Nanosat from Cornell is expected to be flight-ready by September 2007.

The aim of this project is to elucidate the mechanism of thermal runaway in VRLA batteries and especially the eventual role of the AGM separator. The oxygen evolution (OER) and oxygen recombination reactions (ORR) proceed in the cells, and the only work done by the input power is to transfer water from anode to cathode through these reactions, the remaining energy being dissipated as heat. The heat generators in the cell are the electrochemical reactions through their activation overpotentials, the exothermic chemical reactions and the exothermicity of ORR plus Joule Ohmic heating in electrolyte and solid phases. We have shown that, within the range of currents used (up to 1C), the major contribution comes from electrochemical reactions. The cell temperature is at most in a first order dependence of recombinant current. The OER at constant applied voltage and fixed ambient temperature is accelerated by the rise of internal cell temperature and overpotential, as the negative plate is depolarized by ORR due to enhanced separator permeability for oxygen flow by electrolyte displacement and/or drying and negative plate local desaturation. If the negative plate potential is stabilized at Pb/PbSO4 potential and cannot be shifted by any current applied, the cell behaviour is controlled solely by OER reaction. Thus, a lower applied voltage is enough to produce a current sufficient to generate conditions for thermal runaway. The results obtained in this study suggest strongly that by modification of separator properties it is possible to achieve better thermal control, in concert with other cell design improvements, plus the usual external measures as power input management and passive/active cooling., The original document contains color images.

All complex systems, which includes buildings and the built environment, possess emergent properties. Complex systems are systems that are composed of numerous interacting parts. Emergent properties are high-level behaviours that arise spontaneously as a result of the structural organisation of, and the interactions between, the individual parts and properties of the system. Thermal performance is an emergent property of buildings and of the built environment. It is the result of the way in which the physical components of a built environment and their thermal properties interact. Understanding the emergent thermal properties of the built environment is important because there has been an empirically verifiable long term trend in the way classes of buildings have altered over time. Vernacular buildings that have persisted for long spans of time possessed technologies that ‘managed’ the emergent thermal properties, and their inherent thermal contradictions, whether their builders or occupants have been aware of this or not: they are silent technologies. Classes of buildings that did not possess these silent technologies have, over time, fallen out of use and have not reappeared. As buildings have become ever more complex, these silent technologies have become ever more sophisticated overall in their ‘management’ of the emergent thermal properties. This has allowed the overall level of thermal choices and control available to building occupants to increase over time, regardless of their contradictory natures.