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The H+ + HD(v, j) reaction has been investigated in detail by means of a statistical quantum method. State-to-state cross sections and rate constants for transitions between reactants and rovibrational states HD(v′, j′) of the product arrangement with energies below 0.9 eV collision energy [that is, HD(v = 0, j = 0–11) and HD(v = 1, j = 0–6)] have been calculated. For the other product channel, D+ + H2(v′, j′), rovibrational states up to (v′ = 0, j′ = 9) have been considered for the calculation of the corresponding thermal rate. Present predictions are compared with previously reported theoretical and experimental rates. Finally, cooling functions for HD due to proton and atomic hydrogen collisions are computed in the low-density regime. We find that the much larger HD–H+ cooling function, as compared with that of HD–H, does not compensate for the low H+/H abundance ratio in astrophysical media so that HD cooling is dominated by HD–H (or HD–H2) collisions. [ABSTRACT FROM AUTHOR]

High temperature and humidity of many reason of India in the summer season is the major challenge for human comfort also in the drying. In the present work, experiments have been performed to examine the cooling and dehumidification process in the summer season for human comfort and industrial application with the help of calcium chloride (CaCl2) based desiccant material solid desiccant wheel integrated with solar heating arrangements. In this study experimental findings are also evaluated by the mathematical model. During the dehumidification of air in the process unit humidity changes from 17.75 to 29.03 g H2O/kg dry air to 2.8–3.9, 6.8–8.15, 8.92–10.9 & 9.79–11.87 g H2O/kg dry air for flow rate at 1, 2, 3 & 4 m/s, respectively. The process air outlet temperature is increased in the range of 2.58–3.53 K for all air flow rates. After humidification of process outlet air, human comfort condition (HCC) is produced with temperature and humidity in the range of 30–33 °C and 7.77–12.47 g H2O/kg dry air for different air flow rates. Overall airflow for velocity 2–4 m/s can be recommended for the HCC condition. The proposed modelled expression indicates less than 10 % error between the actual and modelled value for different sections. [ABSTRACT FROM AUTHOR]

Energy consumption is an important factor in the operation of machine tools. Recent studies showed that in average, 1 / 5 of the machine tools total energy demand is caused by internal cooling systems. The continually rising performance of machine tools, together with the importance of thermal stability, reasons the requirement for demand oriented cooling approaches, which could significantly reduce the energy consumption for internal machine cooling. This study applied classic and demand oriented cooling strategies on a machine tool frame, which is one of the most complex machine tool components from a thermal point of view. The demand oriented cooling is based on volume flow control and can either be configured close to the environmental temperature or close to the thermal steady state, which can be obtained by loss forecast in combination with an FE model or measurement. The impact of the strategies on the thermal reaction as well as the energy consumption is compared, showing a significant reduction of energy demand without significant impairment of the thermal stability. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the effects of temperature and dissolved oxygen on juvenile largemouth bass during transportation. The experiment involved four temperature groups: 20, 15, 10, and 5 °C. We analyzed the effects of acute and uniform cooling on fish behavior to determine the optimal approach for cooling. Then, we simulated transport under different temperature conditions while measuring the dissolved oxygen level and metabolic rate until all the fish died. The results showed that acute cooling significantly influenced the tail-beat frequency of fish compared with uniform cooling, while abnormal behaviors such as increased swimming, attempted jumping out of the water, and loss of balance were observed. As the transport temperature reduced, the oxygen consumption rate of fish significantly changed at 10 °C, being 2.6 times lower than at 15 °C, with values of 0.10 ± 0.02 and 0.47 ± 0.07 mg·g−1·h−1, respectively. The critical oxygen threshold (Pcrit) of fish were 1.90 ± 0.12, 1.61 ± 0.04, 1.15 ± 0.09, and 1.12 ± 0.25 mg·L−1 at 5, 10, 15, and 20 °C. In addition, below Pcrit, hypoxia-led behavior changes and oxygen consumption rate reduction were observed at every transport temperature. The findings suggest that the optimal low temperature can reduce metabolism and improve the hypoxia tolerance of juvenile largemouth bass. We recommend transporting largemouth bass at an optimal low temperature (15 °C), monitoring fish behavior, and maintaining oxygen levels above Pcrit during transport to prevent stress. [ABSTRACT FROM AUTHOR]

An analytical model to find the temperature field that has been developed for friction systems consists of a strip and semi-space. The strip is made of a two-component functionally graded material (FGM) with an exponentially changing coefficient of thermal conductivity. In contrast, the material of the semi-space is homogeneous. An appropriate boundary-value problem of heat conduction with constant specific friction power was formulated and solved using the Laplace integral transform method. The model takes into consideration the imperfect thermal friction contact between the strip and the semi-space, and also the convective cooling on the exposed surface of the strip. The appropriate asymptotic solutions to this problem for low and high values of Fourier number were obtained. It is shown how the determined exact solution can be generalized using Duhamel's formula for the case of a linearly reduction in time-specific friction power (a braking process with constant deceleration). Numerical analysis for selected materials of the friction pair was carried out in terms of examining the mutual impact on the temperature of the two Biot numbers, characterizing the intensity of the thermal contact conductivity and convective heat exchange on the exposed surface of the strip. The obtained results can be used to predict the temperature of friction systems containing elements made of FGM. In particular, such systems include modern disc braking systems. [ABSTRACT FROM AUTHOR]

The paper considers stresses emerging in the skin of a continuously cast steel billet, as well as their values under the influence of temperature expansions in a novel patented design of a nickel mold with a two-circuit cooling system. According to the known values of heat flux densities at various distances from the top of the mold, the temperature of the slag-forming mixture and the average temperature of the steel billet skin are determined. Based on the established thickness of the billet skin, the temperature gradient therein is determined. At a steel casting speed of 4 m/min, the values of temperature stresses in the billet skin at various distances from the top of the mold were established not to exceed the values of the metal flow stresses at corresponding temperatures. [ABSTRACT FROM AUTHOR]

With the development of eddy current brake (ECB), they are widely used in life and military. Through the ECB, the resistance is converted into thermal energy and dissipated in the air. Thermal energy will make the temperature rise and the heat cannot be dissipated quickly. The electromagnetic characteristics of many parts in the ECB are very sensitive to temperature. Therefore, the study of temperature field is very important for it. This paper takes the linear cylindrical ECB as an example to study the heat generated under the intense impact and high speed condition. The temperature field is calculated through finite element method (FEM) ways. According to the temperature distribution characteristics, the cooling measures of permanent magnet brake are studied to effectively reduce the temperature rise of the brake, ensuring its reliability. [ABSTRACT FROM AUTHOR]

The vertical structure of Arctic warming is of great importance and attracts increasing attention. This study defines two types of Arctic warming events (deep versus shallow) according to their temperature profiles averaged over the Barents–Kara Seas (BKS), and thereupon compares their characteristics and examines their difference in generation through thermodynamic diagnoses. A deep Arctic warming event—characterized by significant bottom-heavy warming extending from the surface into the middle-to-upper troposphere—emanates from the east of Greenland and then moves downstream toward the BKS primarily through zonal temperature advection. The peak day of deep warming event lags that of the precipitation and resultant diabatic heating over southeast Greenland by about four days, suggesting that the middle-to-high tropospheric BKS warming is likely triggered by the enhanced upstream convection at the North Atlantic high latitudes. In contrast, a shallow warming event—manifested by warming confined within the lower troposphere—is preceded by the meridional advection of warm air from inland Eurasia. These anomalous southerlies over Eurasian lands during shallow warming events are related to the eastward extension of the deepened Icelandic low. During deep warming events, the in situ reinforcement of the Icelandic low favors abundant moisture transport interplaying with the southeast Greenland terrain, leading to intense precipitation and latent heat release there. Both deep and shallow warming events are accompanied by Eurasian cooling, but the corresponding cooling of the deep warming event is profoundly stronger. Further, intraseasonal deep Arctic warming events could explain nearly half of the winter-mean change in the warm Arctic–cold Eurasia anomaly. Significance Statement: Divergent conclusions on whether Arctic warming is influencing the midlatitudes impede a clear understanding of the warm Arctic–cold Eurasia (WACE) phenomenon. Recent findings that on the interannual or longer time scales, Eurasian cooling tends to occur in the presence of deep rather than shallow Arctic warming have attracted increasing concern regarding the vertical structure of Arctic warming. On this basis, here we classify intraseasonal Arctic warming events into deep and shallow groups and contrast them from various aspects. Emerging near eastern Greenland and associated with upstream convection activities, intraseasonal deep Arctic warming events are accompanied by significant Eurasian cooling, largely determining the seasonal-mean WACE condition. However, caused by meridional temperature advection from Eurasian lands, shallow warming events less correlate with Eurasian cooling. [ABSTRACT FROM AUTHOR]

The booster-driven hybrid cooling unit using ambient energy for free cooling can work for a whole year as one unit and reduce the annual cooling energy consumption effectively in data centers. Two different type booster and its hybrid cooling units were developed and tested. The suction/discharge pressure and mass flow rate of two different boosters were studied under the annual temperature difference range. The performance and differences of two hybrid cooling units were analyzed. The results indicate that the suction/discharge pressure ratio of the large torque booster (No.1) is less than that of the small torque booster (No.2). In the test temperature difference range, the suction/discharge pressure ratio of No.1 booster decreases by 53.56%,which of No.2 booster decreases by 32.89%. The cooling capacity and energy efficiency ratio of No.1 booster-driven hybrid cooling unit (14.8 kW) is higher than that of No.2 booster unit（9.2 kW） at the same temperature difference（30℃） [ABSTRACT FROM AUTHOR]

An exact solution of the boundary-value problem of heat conduction was obtained with consideration of heat generation due to friction and convective cooling for the strip/semi-space system. Analytical solutions to this problem are known for the case with both friction elements made of homogeneous materials or a composite layer with a micro-periodic structure. However, in this study, the strip is made of a two-component functionally gradient material (FGM). In addition, the exact, asymptotic solutions were also determined at small and large values of the Fourier number. By means of Duhamel's theorem, it was shown that the developed solution for a constant friction power allows to obtain appropriate solutions with a changing time profile of this value during heating. Numerical analysis in dimensionless form was carried out for the FGM (ZrO2—Ti-6Al-4V) strip in combination with the cast iron semi-space. The influence of the convective cooling intensity (Biot number) on the temperature field in the considered friction system was investigated. The developed mathematical model allows for a quick estimation of the maximum temperature of systems, in which one of the elements (FGM strip) is heated on the friction surface and cooled by convection on the free surface. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide OBJECTIVES Core temperature monitoring is critical during cardiopulmonary bypass (CPB). In this prospective observational study, we investigated the performance of the transoesophageal echocardiography (TOE) probe for core (oesophageal) temperature monitoring during CPB. METHODS Thirty adult patients, 18–70 years of either gender, undergoing cardiac surgery with CPB were enrolled. All patients received a reusable nasopharyngeal probe for monitoring core temperatures. In addition, the oesophageal temperatures were monitored with the TOE probe. The arterial outlet temperatures at the membrane oxygenator were also monitored and taken as the reference standard. Monitoring was performed every 5 min until 20 min, and then at 30 min during both the cooling and rewarming periods. RESULTS During cooling, the oesophageal and nasopharyngeal temperatures lagged behind the arterial outlet temperatures. However, the intra-class correlation of the oesophageal temperatures with the arterial outlet temperatures was better (range 0.58–0.74) than the correlation of the nasopharyngeal temperatures with the arterial outlet temperatures (range 0.46–0.62). During rewarming, the performance of the TOE probe was significantly superior to the nasopharyngeal probe. After 15 and 20 min of rewarming, there was a difference of ∼1°C between the oesophageal and nasopharyngeal temperatures. At 30 min of rewarming, the oesophageal and the arterial outlet temperatures were similar, while the nasopharyngeal temperatures still lagged by 0.5°C. Bias was significantly less both during cooling and warming between the oesophageal temperatures and arterial outlet temperatures. CONCLUSIONS Performance of the TOE probe as an oesophageal temperature probe is superior to the nasopharyngeal probe during CPB. Clinical trial registration number CTRI no 2020/10/028228; ctri.nic.in. [ABSTRACT FROM AUTHOR]

Ambient temperature control and active internal cooling can effectively reduce the impact of spindle thermal error. At the same time, the residual spindle thermal error fluctuates violently, which makes it difficult to predict the thermal error accurately. To combat this issue, experiments to identify the spindle thermal error with constant and variable spindle speed spectrums were designed. A deep learning model is proposed for thermal error prediction, wherein speed parameter is incorporated as an input variable alongside temperature variables. The proposed model adopts a 1D convolutional neural network-gated recurrent unit-attention (1DCNN-GRU-Attention) architecture. Within this model, the 1DCNN module is responsible for managing the highly collinear input data and extracting spatial information, followed by the GRU module which extracts temporal information. Furthermore, the attention mechanism of the model can re-weight the learned features. Ultimately, the regression layer is responsible for predicting thermal error. To verify the proposed model's effectiveness, it was compared against seven other thermal error prediction models. The experimental results revealed that the convolutional module of the proposed model is highly effective and can replace the traditional temperature-sensitive point selection (TPS) method. Under multiple coupled factors, the proposed method achieved a prediction accuracy of 81.53%, with root-mean-square error (RMSE) lower than the traditional method by 40%. [ABSTRACT FROM AUTHOR]

All sections of a single-screw extruder must be operating well to maintain the maximum profitability of the line. The solids conveying section must be able to operate at a rate high enough to keep the metering section full of resin and pressurized. Optimal solids conveying depends on the forwarding and retarding forces on the solid bed, and these forces depend on the barrel and screw temperatures. Usually, a considerable level of care is given to setting the barrel and feed casing temperatures. The temperature of the screw, however, is typically not controlled. Instead, the screw temperature is unknown and often hotter than optimal. Screw cooling can improve solids conveying for many processes. This paper discusses the fundamentals and operational practices for using screw cooling. [ABSTRACT FROM AUTHOR]

Environmental challenges faced early in life can both activate and shape the development of the hypothalamic-pituitary-adrenal axis. Activation of this axis is characterized in part by elevated levels of glucocorticoids, exposure to which can have profound effects throughout an animal's life. We have demonstrated that in nestling eastern bluebirds (Sialia sialis), bouts of environmentally relevant cooling result in elevations of corticosterone (the primary avian glucocorticoid) very early in life. Nestlings repeatedly exposed to cooling also exhibit dampened corticosterone secretion later in life in response to restraint compared to control nestlings. We explored the mechanistic basis of this phenomenon. Specifically, we asked whether early-life cooling alters adrenal sensitivity to adrenocorticotropic hormone (ACTH), the primary controller of corticosterone synthesis and release. To this end, we subjected nestlings to repeated bouts of cooling (cooled nestlings) or brooding temperatures (control nestlings) early in life and, before fledging, assessed (1) the capacity of the nestlings' adrenals to produce corticosterone following ACTH injection, (2) the effect of cooling on corticosterone responses to restraint, and (3) the effect of cooling on adrenal sensitivity to ACTH. We found that both cooled and control nestlings secreted substantially higher levels of corticosterone following ACTH treatment than they did following restraint. We also confirmed that cooled nestlings had reduced corticosterone secretion in response to restraint compared to control nestlings; however, sensitivity to exogenous ACTH did not differ between temperature treatments. We hypothesize that early-life cooling alters later corticosterone secretion by affecting higher levels of the hypothalamic-pituitary-adrenal axis. [ABSTRACT FROM AUTHOR]

Simple Summary: Despite recommendations for, and the prevalence of, passive rest amongst heat-exposed occupational groups to mitigate heat stress, there is limited information regarding the effectiveness of this control measure. This systematic review of post-work core temperature cooling rates conferred by passive rest reports that 8 of the 50 included datasets failed to indicate cooling. Of the remaining 42 datasets, only 10 indicated core temperature cooling rates exceeding 0.034 °C min−1 or ~0.5 °C per 15 min, with participants wearing athletic attire or similar in each of these studies. Cooling during passive rest while wearing more insulative work attire or similar was only achieved in 7 of 13 datasets. Irrespective of its widespread implementation, these findings indicate that passive rest does not reverse the elevated core temperatures of heat-exposed workers in a timely manner. Alternative cooling methods are required to mitigate heat stress now and into the future. Physical work increases energy expenditure, requiring a considerable elevation of metabolic rate, which causes body heat production that can cause heat stress, heat strain, and hyperthermia in the absence of adequate cooling. Given that passive rest is often used for cooling, a systematic search of literature databases was conducted to identify studies that reported post-work core temperature cooling rates conferred by passive rest, across a range of environmental conditions. Data regarding cooling rates and environmental conditions were extracted, and the validity of key measures was assessed for each study. Forty-four eligible studies were included, providing 50 datasets. Eight datasets indicated a stable or rising core temperature in participants (range 0.000 to +0.028 °C min−1), and forty-two datasets reported reducing core temperature (−0.002 to −0.070 °C min−1) during passive rest, across a range of Wet-Bulb Globe Temperatures (WBGT). For 13 datasets where occupational or similarly insulative clothing was worn, passive rest resulted in a mean core temperature decrease of −0.004 °C min−1 (−0.032 to +0.013 °C min−1). These findings indicate passive rest does not reverse the elevated core temperatures of heat-exposed workers in a timely manner. Climate projections of higher WBGT are anticipated to further marginalise the passive rest cooling rates of heat-exposed workers, particularly when undertaken in occupational attire. [ABSTRACT FROM AUTHOR]

The utilization of automotive engine components for the development of a reverse Brayton cycle is shown in this study. The well-known characteristics of turbochargers and electrical centrifugal compressors commonly used in the automotive industry are a starting point for developing an experimental cycle configuration of a reverse Brayton refrigeration cycle with the ability to achieve up to 115 K after a multistage compression with intermediate cooling and a single-stage expansion in a radial turbine using air (R-729) as working fluid. The use of a variable nozzle turbine allows us to evaluate the optimum rack position for each operating point, as well as having control over refrigeration capacity. Studies over the minimum cycle pressure at the inlet of the first stage of compression have been performed to assess the possible benefit of creating vacuum or pressurize the working fluid. A 1 m³ cooling chamber was attached to the installation to test the ability of cooling different thermal loads working under different operation ways, open or closed cycle, this is, letting the working fluid interact with the thermal load or cooling it through a heat exchanger. The evaluation of thermodynamic parameters allows us to obtain the coefficient of performance (COP) of the installation as well as the efficiency of each component. The analysis of turbomachinery performance will allow identifying weak points to improve cycle performance, and improve the coupling model between the rotatory machines as well as adapt the size of the installation to the refrigeration capacity required for different applications. [ABSTRACT FROM AUTHOR]

The integration of a heat pump (HP) with a combined cycle gas turbine (CCGT) to control the inlet air temperature is a promising technology to meet the requirements imposed by the current electricity systems in terms of efficiency and flexibility. If the HP is coupled with a thermal energy storage (TES) in an inlet conditioning unit (ICU), it can be exploited in different modes to enhance the off-design CCGT's efficiency or to boost the power output at full load. Furthermore, fuel-saving would be reflected in avoided emissions. The optimal sizing of the ICU, as well as an accurate estimation of the benefits, is a complex problem influenced by several factors such as the local climate and electricity market prices. This paper aims to systematically investigate, utilizing a mixed integer linear programming (MILP) model for optimal dispatch, the feasibility of an ICU integration in different scenarios (EU and US). Different electricity markets have been analyzed and classified according to the parameters describing the average and variability of prices, the interdependency with the gas market, the ambient temperature, or the local carbon pricing policy. The most favorable conditions are identified and the dependency of the optimal ICU sizing on the climate and the electricity market is highlighted. This paper provides information for a first viability assessment: the concept appears to be highly profitable in hot regions with high price variability. Additionally, even in less profitable conditions (i.e., stable low prices in a cold climate), the system increases operating hours and reduces economic losses. [ABSTRACT FROM AUTHOR]

Purpose: Foot sole cooling increases vestibular-evoked balance responses, but less is known about foot dorsum temperature alterations. The purpose was to determine whether decreasing cutaneous receptor sensitivity via foot dorsum cooling modulates the vestibular control of balance. Methods: Eighteen participants (9 males; 9 females) stood quietly on a force plate with feet together, eyes closed, and head rotated leftward during 4, 90-s trials (2 control; 2 cooled) of continuous electrical vestibular stimulation (EVS). Icepacks placed on the dorsum of both feet for 15 min induced cooling and remained throughout the EVS trials. Monofilament testing was performed at multiple locations before and after cooling to determine tactile detection thresholds. T-type thermocouples monitored skin temperature over the tibialis anterior, soleus, foot dorsum and arch of the right leg. Vestibular-evoked balance responses were characterized using time (cumulant density) and frequency (coherence and gain) domain analyses to determine the relationship between the EVS input and motor output (anteroposterior force—AP force; right medial gastrocnemius electromyography—MG EMG). Results: Skin temperature of the foot dorsum and arch decreased ~ 70 and 15%, respectively during cooling (p < 0.05), but was unaltered at other locations (p ≥ 0.10). Detection thresholds for the foot dorsum increased following cooling (p < 0.05). Surprisingly, cooling reduced EVS-AP force and EVS-MG EMG coherence and gain at multiple frequencies, and peak-to-peak amplitude compared to control (p < 0.05). Conclusion: Our results indicate that vestibular-driven balance responses are reduced following foot dorsum cooling, likely owing to alterations in cutaneous mechanoreceptor sensitivity and subsequent alterations in the transformation of vestibular cues for balance control. [ABSTRACT FROM AUTHOR]

Among the technologies for carbon capture and storage (CCS) from natural gas, oxy-turbine plants are a very promising solution thanks to the high efficiency, absence of stack, and nearly 100% capture rate. This aper investigates the efficiency which can be achieved by the semi-closed oxy-combustion combined cycle (SCOC-CC) with state-of-the-art and future blade materials. In particular, the analysis considers class-H turbine superalloys with a maximum blade wall temperature of 900 °C and ceramic matrix composites with blade wall temperatures of 1300 °C. Sensitivity analyses are performed to determine the optimal pressure ratio and turbine inlet temperature. The results indicate that state-of-the-art superalloys allow the SCOC-CC to achieve 54% net electric efficiency with a 96% carbon capture rate, while ceramic matrix composite (CMC) blades boost the efficiency up to 60%. For both cases, critical factors are the high temperature gradients across the blade coatings (thermal barrier coating (TBC) for superalloy, environmental barrier coating (EBC) for CMC) and the blade thickness caused by the large heat flux exchanged between hot gases and cooling flows. [ABSTRACT FROM AUTHOR]

Although temperature can significantly affect the stability and degradation of drug nanosuspensions, temperature evolution during the production of drug nanoparticles via wet stirred media milling, also known as nanomilling, has not been studied extensively. This study aims to establish both descriptive and predictive capabilities of a semi-theoretical lumped parameter model (LPM) for temperature evolution. In the experiments, the mill was operated at various stirrer speeds, bead loadings, and bead sizes, while the temperature evolution at the mill outlet was recorded. The LPM was formulated and fitted to the experimental temperature profiles in the training runs, and its parameters, i.e., the apparent heat generation rate Qgen and the apparent overall heat transfer coefficient times surface area UA, were estimated. For the test runs, these parameters were predicted as a function of the process parameters via a power law (PL) model and machine learning (ML) model. The LPM augmented with the PL and ML models was used to predict the temperature evolution in the test runs. The LPM predictions were also compared with those of an enthalpy balance model (EBM) developed recently. The LPM had a fitting capability with a root-mean-squared error (RMSE) lower than 0.9 °C, and a prediction capability, when augmented with the PL and ML models, with an RMSE lower than 4.1 and 2.1 °C, respectively. Overall, the LPM augmented with the PL model had both good descriptive and predictive capability, whereas the one with the ML model had a comparable predictive capability. Despite being simple, with two parameters and obviating the need for sophisticated numerical techniques for its solution, the semi-theoretical LPM generally predicts the temperature evolution similarly or slightly better than the EBM. Hence, this study has provided a validated, simple model for pharmaceutical engineers to simulate the temperature evolution during the nanomilling process, which will help to set proper process controls for thermally labile drugs. [ABSTRACT FROM AUTHOR]

Phenotypic convergence across distantly related taxa can be driven by similar selective pressures from the environment or intrinsic constraints. The roles of these processes on physiological strategies, such as homeothermy, are poorly understood. We studied the evolution of thermal properties of mammalian pelage in a diverse community of rodents inhabiting the Mojave Desert, USA. We used a heat flux device to measure the thermal insulation of museum specimens and determined whether thermal properties were associated with habitat preferences while assessing phylogenetic dependence. Species that prefer arid habitats exhibited lower conductivity and thinner pelage relative to species with other habitat preferences. Despite being thinner, the pelage of arid species exhibited comparable insulation to the pelage of the other species due to its lower conductivity. Thus, arid species have insulative pelage while simultaneously benefitting from thin pelage that promotes convective cooling. We found no evidence of intrinsic constraints or phylogenetic dependence, indicating pelage readily evolves to environmental pressures. Thermoregulatory simulations demonstrated that arid specialists reduced energetic costs required for homeothermy by 14.5% by evolving lower conductivity, providing support for adaptive evolution of pelage. Our study indicates that selection for lower energetic requirements of homeothermy has shaped evolution of pelage thermal properties. [ABSTRACT FROM AUTHOR]

In the current energy scenario, gas turbine combined cycles (GTCCs) are considered key drivers for the transition towards fossil-free energy production. However, to meet this goal, they must be able to cope with rapid changes in power request and extend their operating range beyond the limits imposed by the environmental conditions in which they operate. The European H2020 project PUMP-HEAT (Pump-Heat Project, 2021, D4. 6 - "Validation Results in Energy -Hub of MPC With Cold Thermal Storage,") aims at achieving this goal thanks to the integration of the GTCC with a heat pump (HP) and a thermal energy storage (TES). To study this setup, a dedicated cyber-physical facility was built at the University of Genova laboratories, Italy. The plant includes physical hardware, such as a 100kWel microgas turbine, (mGT), a 10 kWel HP and a 180 kWh change phase material-based TES. These real devices are up-scaled thanks to performance maps and real-time dynamic models to emulate a full-scale heavy-duty 400 MW GTCC with a cyber-physical approach. The control system determines the optimal configuration of the whole plant and the operative point of the real devices to minimize the mismatch with a real electric power demand curve. Different operative configurations are tested: one for reducing the power production of the plant below the minimum environmental load (MEL) and two for augmenting the plant maximum power under certain ambient conditions. From the analysis of these tests, it is possible to verify the effectiveness of the proposed concept and characterize the transient behavior of the real components. [ABSTRACT FROM AUTHOR]

• The literature available on floating photovoltaic (FPV) temperatures is reviewed. • Water-cooled FPV are expected to achieve lower temperatures than air-cooled FPV. • The thermal behaviour of FPV varies depending on the design and the local conditions. • Wind is the main cooling agent for FPV systems installed above water surface. • More experimental and comparative studies on the topic are recommended. In floating photovoltaics (FPV), modules are installed on water to alleviate the land requirement of this energy source. In addition, FPV installations are expected to work at lower operating temperatures compared to land based photovoltaic (LPV) systems, thanks to the cooling effect of water. If confirmed, these lower temperatures would (i) increase the energy yield and (ii) reduce degradation and performance losses, boosting the cost-competitiveness of FPV. However, some recent works have reported cases of FPV systems working at higher temperatures than co-located LPV systems. The present review gathers the literature on the thermal behaviour of FPV, outlining the models and discussing the currently available experimental results. It is found that FPVs of different configurations can experience different thermal behaviours, not always necessarily better than LPV. In particular, air- and water-cooled FPV systems should be always distinguished, considering their diverse cooling mechanisms. Initial comparative analyses make it possible to identify designs and conditions that can favour the heat transfer in FPV compared to LPV. The role of additional factors on the FPV temperature, such as the PV material or the more frequent biofouling, is also discussed. Last, estimations of the economic impact of the thermal behaviour on the FPV costs and competitiveness are presented. [ABSTRACT FROM AUTHOR]

Refrigerant pump-driven free cooling technology can effectively reduce data center cooling energy consumption.But for a pure refrigerant system,it is difficult to meet the need of dynamic high efficient operation facing both the large temperature difference range and multiple operating modes yearly.In order to improve the energy efficiency of the system and the utilization of free cooling source,an experimental system of refrigerant pump driving free cooling for the data center was built up.The thermal performance of the system charged with R410 A mixed refrigerant was tested and analyzed under different working conditions.The results show that the cooling capacity and EER of the system increase with the increasing of the temperature difference between cold and heat sources.The cooling capacity increases firstly and then decreases slightly,then changes little within the pump frequency range of 5～30 Hz.The pump frequency for maximum cooling capacity occurs in the range of 10～15 Hz for R410 A system,which is 25 Hz for R22 system [ABSTRACT FROM AUTHOR]

This paper proposes a load transfer optimization (LTO) model involving hot-spot temperature (HST) and top-oil temperature (TOT) limits of transformers. This work aims to address the overload problem and transformer HST and TOT excursions via LTO. First, the equivalent thermal model for the HST and TOT of transformers under external cooling conditions are discussed, and then the corresponding linearized HST and TOT constraints with varied thermal resistances are derived using the discretization method. Moreover, the proposed LTO model is formulated on the reconfigurable topology of high voltage distribution networks (HVDNs) in China. This proposed LTO model can achieve the optimal network reconfiguration scheme subject to temperature limits and system operation constraints, with the least switching operation cost and the maximum margins of reactive power exchange between HVDNs and transmission systems. Finally, the effectiveness of the proposed LTO model is validated by the modified IEEE-14 node system and the practical HVDNs in China. [ABSTRACT FROM AUTHOR]

Temperature management is an essential element of cardiopulmonary bypass (CPB), as indicated in the Guide to Good Practice in Clinical Perfusion, 'The safe conduct of CPB requires the clinical perfusionist to measure and control... blood temperature... during the period of bypass'. To review current practice, we have conducted a research survey into the management of temperature on CPB. Surveys were distributed to each centre in Great Britain and the Republic of Ireland, investigating numerous temperature management practices, to elucidate current practice and assess if recent research into temperature management marry routine clinical practice. Our results demonstrate that nasopharyngeal temperature is the most common (52%) temperature site used across the many centres, which correlates with previous research as a routine site for cerebral temperature management. The arterial outlet of the oxygenator temperature was used in 33% of centres, however, all centres lacked the knowledge to maintain this temperature below 37°C. There was significant variation between all centres, especially regarding rewarming times (20–40 minutes), demonstrating a lack of uniformity among perfusion centres. Interestingly, most centres have been using the same protocol that has been in place over the previous 10 years. To conclude, the practice of temperature management is changing with the awareness of new research. Lower target temperatures are recommended for rewarming, ensuring a lower temperature gradient and a longer mean rewarming time. [ABSTRACT FROM AUTHOR]

This work presents the design of an inexpensive electronic system to measure water temperature and generate an experimental data set used to verify the fitting between experimental and theoretical curves of a water-cooling process. The cooling constant is computed with three different theoretical methods to check their efficiency and this approach allows the association of theoretical and experimental aspects of physics, mathematics and electronic instrumentation, which can motivate interesting discussions in the classroom. [ABSTRACT FROM AUTHOR]

How do occupants' behaviour and expectations influence energy use for residential geothermal air-conditioning? This detailed study of 40 homes with geothermal AC in Sydney, Australia, during the period 2019-20 covers one of hottest Australian summers and increased daytime occupancy over the winter due to working from home during Covid-19 lockdowns. Monitored data are analysed for ground source heat pump (GSHP)-AC energy, occupancy, indoor conditions, as well as a snapshot resident feedback captured during hot and cold spells. Findings indicate that the homes built to comply with 2011 energy efficiency standards maintain indoor temperatures within 10-12°C of peak summer and minimum winter temperatures, without AC. A general preference to adopt adaptive strategies such as ceiling fans and appropriate clothing before deploying AC is evident for moderately hot and cold days. A heightened dependence on AC is seen for extreme days. However, a significant number of houses adhere to a narrow range of acceptable temperatures, thereby increasing the take-up of GSHP-AC and energy consumption. The replacement of conventional AC with alternate technologies is not a one-stop solution in, and of, itself. There is a need for improved building low energy design and construction based on a better understanding of occupant behaviour and energy consequences. [ABSTRACT FROM AUTHOR]

While building stock modelling has been used previously to investigate the space heating demand implications of national energy efficiency retrofitting, there are also implications for indoor overheating and air quality, particularly in schools, with highly intermittent occupancy patterns. This paper assesses indoor overheating risk and air quality within an English classroom stock model containing 111 archetypes, based on the analysis of the nationwide Property Data Survey Programme (PDSP) containing 9629 primary school buildings in England. Metrics for indoor temperatures, heating demand and concentrations of three contaminants (CO2, NO2, PM2.5) were estimated in naturally ventilated classrooms, while exploring future climate projections, retrofit and overheating mitigation scenarios to analyse school stock resilience. Classrooms with a south-east orientation experience around four to six times the overheating-hours compared with those with a northern orientation. Post-1976 archetypes are most susceptible to overheating, indicative of the conflict between better insulated and airtight classrooms and overheating prevention. A range of retrofit and passive cooling measures can mitigate against overheating alone, although mechanically driven cooling and filtration may be required towards the 2080s. While no single measure predicted universally positive effects for building performance, night ventilation and overhangs were found to be particularly effective passive overheating mitigation methods across the school stock. [ABSTRACT FROM AUTHOR]

We study the translational single particle dynamics of hydration water of lysozyme upon cooling by means of molecular dynamics simulations. We find that water close to the protein exhibits two distinct relaxations. By characterizing their behavior upon cooling, we are able to assign the first relaxation to the structural a-relaxation also present in bulk water and in other glass-forming liquids. The second, slower, relaxation can be ascribed to a dynamic coupling of hydration water motions to the fluctuations of the protein structure. Both relaxation times exhibit crossovers in the behavior upon cooling. For the a-process, we find upon cooling a crossover from a fragile behavior to a strong behavior at a temperature which is about five degrees higher than that of bulk water. The long-relaxation time appears strictly connected to the protein motion as it shows upon cooling a temperature crossover from a strong behavior with a lower activation energy to a strong behavior with a higher activation energy. The crossover temperature coincides with the temperature of the protein dynamical transition. These findings can help experimentalists to disentangle the different information coming from total correlators and to better characterize hydration water relaxations in different biomolecules. [ABSTRACT FROM AUTHOR]

Crystallization of lysozyme is investigated upon rapid cooling to 4°C of undersaturated solutions equilibrated at temperatures in the range 30°C–44°C, and for incubation times varying from 12 to 36 min. The results indicate a tendency for the crystallization systems to respond in such a way that a solution of lower supersaturation may produce crystal populations of higher density. Analysis of the average crystal size shows that higher supersaturations might still be responsible for earlier nucleation, and the effects of solution incubation temperature (and its rapid decrease) are most likely on the dynamics of pre-crystallization protein–protein interactions, e.g. on the processes of formation of clusters/aggregates that could serve as active centers for nucleation, or as structures depleting the effective supersaturation for nucleation. The study demonstrates that lysozyme crystal nucleation could be strongly influenced by sharp temperature variation as long as crystallization systems of relatively low final supersaturation are investigated. [ABSTRACT FROM AUTHOR]

Direct cooling of the windings in a motor using oil offers more effective thermal management than conventional alternatives and can therefore increase the torque density of electric machines; however, this technique is limited by the thermophysical properties of the oil. The use of a direct winding heat exchanger allows a glycol-water coolant mixture to be used, which leads to a significant improvement in heat transfer and a reduction in the pumping losses compared to direct oil cooling. This article proposes ceramic 3-D printed direct winding heat exchangers (3D-DWHX), which can significantly improve the cooling of windings in electric machines due to the unique geometries enabled by 3-D printing. Ceramics are also capable of withstanding extremely high temperatures, which extends the application of the proposed 3D-DWHX. A closed-form analytical thermal model incorporating the temperature dependence of winding losses is proposed and used with empirical heat transfer correlations to design a microfeature enhanced 3D-DWHX. The ceramic 3D-DWHX was built and tested in a motorette that demonstrated a continuous current density of 35.7 ARMS/mm2, corresponding to a continuous specific power in the reference electric machine of at least 12.1 kW/kg while keeping the maximum winding temperature below 200 °C. [ABSTRACT FROM AUTHOR]

Impingement cooling is an effective method for removing heat from a high temperature target surface using sprayed jets oriented to impinge on the surface. Detailed local heat-/mass-transfer distributions are measured using the naphthalene sublimation method. The main parameters of this study are jet hole spacing (s/d = 4, 8) and crossflow rate. The heat-/mass-transfer coefficients on the target surface are significantly influenced by the crossflow volume and pin-fin structures, and the degree of this influence is affected by different jet hole spacings. The results indicate that a small hole spacing increases the heat/mass transfer by 15%–30% than a large hole spacing for the Reynolds number of 15 000. [ABSTRACT FROM AUTHOR]

This study compared neuromechanical characteristics of voluntary (maximum voluntary contraction (MVC) peak torque, rate of torque development (RTD), voluntary activation (VA)) and electrically stimulated contractions (peak torque, RTD) when performed under the same temperature conditions. Twelve physically active males performed two isometric MVCs of the quadriceps muscle group in an isokinetic dynamometer. The MVCs were performed after lower limb submersion for 20 min in hot (40°C) or cold (10°C) water. A control MVC was performed in ambient room temperature (17 ± 0.7°C). Electrical twitches were delivered at rest pre-MVC (Unpotentiated), during the plateau phase of the MVC (Superimposed) and post-MVC (Potentiated). Peak torque for MVC, Unpotentiated and Potentiated was recorded. RTD was calculated for the MVC (at 50, 100, 150, 200 ms and peak torque time points), Unpotentiated and Potentiated twitches, while VA (using the central activation ratio method) was calculated. There was no significant change between conditions in MVC peak torque, MVC RTD, VA and (averaged) twitch peak torque (p > 0.05). Twitch RTD for the hot condition (1025.0 ± 163.0 N·m·s−1) was significantly higher (p = 0.003) than control (872.3 ± 142.9 N·m·s−1). In conclusion, environmental temperature changes, in the range examined, do not affect the ability to generate maximum torque or any of the RTD parameters in maximum voluntary isometric contractions. In contrast, increased heat results in higher RTD in electrically stimulated contractions, most likely induced by reduced contraction time. This has practical implications for the use of electromyostimulation for injury prevention. [ABSTRACT FROM AUTHOR]

Aim: To perform a systematic review and meta-analysis on targeted temperature management in adult cardiac arrest patients.Methods: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched on June 17, 2021 for clinical trials. The population included adult patients with cardiac arrest. The review included all aspects of targeted temperature management including timing, temperature, duration, method of induction and maintenance, and rewarming. Two investigators reviewed trials for relevance, extracted data, and assessed risk of bias. Data were pooled using random-effects models. Certainty of evidence was evaluated using GRADE.Results: The systematic search identified 32 trials. Risk of bias was assessed as intermediate for most of the outcomes. For targeted temperature management with a target of 32-34 °C vs. normothermia (which often required active cooling), 9 trials were identified, with six trials included in meta-analyses. Targeted temperature management with a target of 32-34 °C did not result in an improvement in survival (risk ratio: 1.08 [95%CI: 0.89, 1.30]) or favorable neurologic outcome (risk ratio: 1.21 [95%CI: 0.91, 1.61]) at 90 to 180 days after the cardiac arrest (low certainty of evidence). Three trials assessed different hypothermic temperature targets and found no difference in outcomes (low certainty of evidence). Ten trials were identified comparing prehospital cooling vs. no prehospital cooling with no improvement in survival (risk ratio: 1.01 [95%CI: 0.92, 1.11]) or favorable neurologic outcome (risk ratio: 1.00 [95%CI: 0.90, 1.11]) at hospital discharge (moderate certainty of evidence).Conclusions: Among adult patients with cardiac arrest, the use of targeted temperature management at 32-34 °C, when compared to normothermia, did not result in improved outcomes in this meta-analysis. There was no effect of initiating targeted temperature management prior to hospital arrival. These findings warrant an update of international cardiac arrest guidelines. [ABSTRACT FROM AUTHOR]

This article presents an experimental investigation of two-phase passive liquid cooling, using a miniature-thermosyphon, for the simulated three-dimensional stacked integrated chips (3D-SICs). An evaporator consisting of three heaters separated with two micro-gaps of height 0.178 mm serves as a core component of the miniature-thermosyphon system. The thermosyphon’s cooling performance has been evaluated under multiple parametric conditions, including evaporator tilt angle, vertical separation between the condenser and the evaporator, and inlet-chilled water temperature of the condenser in the auxiliary loop. Boiling regimes at evaporator outlets are presented. All the investigated characteristics except the tilt angle have notable impacts on the cooling performance of each layer of the simulated 3D-SICs. Nonuniform cooling performance between the simulated 3D-SICs layers and within each layer has been observed. This nonuniform cooling performance could require the preferred placement of 3D-SICs with heterogeneous chips in data center cabinets. [ABSTRACT FROM AUTHOR]

In this work, we study the development of vortical structures generated in a rotating cylinder non-homogeneously cooled on the top. In the axisymmetric regime, for moderate vertical temperature differences and any rotation rate, cyclonic and anticyclonic rotations coexist in the flow: a counterclockwise motion at upper levels, giving place to a vertical top-down vortex, and a clockwise rotation at lower levels that generates a spin up motion. For lower rotation rates and high enough vertical temperature differences, only cyclonic top-down vortices survive and get stronger. We perform a force balance analysis to explain the phenomena. In the non-axisymmetric regime, no anticyclonic rotation at the bottom is reported and the cyclonic top-down vortex either disappears or splits up in two top-down vortices, depending on the ambient rotation rate. The intensity of the cooling on the top and how localized this cool region is affect the flow developed. When the horizontal temperature difference on the top is larger than the vertical temperature difference between top and bottom, stable axisymmetric top-down vortices with an inner updraft of warmer air are reported. The more localized the cooling above, the more difficult the development of the inner updraft becomes. Results may contribute to the understanding of the relevance of thermal processes in tornadogenesis. [ABSTRACT FROM AUTHOR]

The maximum firing temperature of a gas turbine (GT) is limited by material constraints. Critical for the operation of the GT is the blade metal temperature, which is impacted by the heat transfer from the combustor outlet gas to the blade surface. In this study, performance characteristics for an H-class-type GT have been established and two correlations for the change in the maximum permissible firing temperature as function of combustor outlet gas composition or flue gas composition and pressure ratio have been derived: (I) for detailed GT modeling with cooling flows and (II) for simplified GT modeling without specifying cooling flows. [ABSTRACT FROM AUTHOR]

Machining with minimum quantity lubrication (MQL) or minimum quantity cooling (MQC) as a subset of green machining is a process in which small volume fluid of high lubrication and cooling properties alongside high pressure air is used in the material removal process. The heat generated in the grinding process has a great impact upon the workpiece quality. Serving lubrication and heat transfer functions, cutting fluids have an essential role in reducing the temperature and thus improving the process of grinding. In this research, nanofluid made of graphene nanoparticles in water-based fluid as a cutting fluid of high heat transfer is utilized to investigate the effects of nozzle number and nozzle geometry of the MQC system on the cutting temperature and surface roughness of the workpiece. The effect of geometry and number of nozzles on grinding with MQC has not been studied so far. The study findings show that the nozzle outlet cross-section of rectangular, compared to circular, decreases the surface roughness and temperature by 30% and 36%, respectively. Moreover, compared to the single nozzle, the use of three nozzles results in a decrease of 19% and 31.7% in the surface roughness and temperature. Under the same machining conditions, the MQC method by 0.15 wt.% nanofluid of graphene in water using a rectangular nozzle outlet of 1.2 mm width makes surface roughness and temperature reduced by 67.2% and 48.3% compared to the dry condition, whereas decreased by 13.4% and 8.8% compared to the wet method, respectively. [ABSTRACT FROM AUTHOR]

Summary: The application of an inorganic phase change material (PCM) on instrument panel for temperature control is reviewed here through numerical simulation. A constant heat flux is provided on one face of the panel, and the inhibited temperature build‐up is studied for different modes of PCM placement. The distribution of microencapsulated PCM over the surface of the panel as embedded in the paint layer reduces the temperature gradient that is unavoidable for lumped placement at one location on the panel, which also affects the average temperature. The effect of the size of microcapsules, ranging from mm to μm scale on characteristics of temperature build‐up, is reported here under two different exposure conditions of upper surface of the paint layer, that is, natural convection and fully insulated condition. The cooling characteristics of the panel in the absence of heat flux are presented. [ABSTRACT FROM AUTHOR]

In several regions worldwide, demand for electricity can be highly dependent on weather conditions. This study investigates the relationships between weather and electricity consumption in three West African cities. Monthly electricity consumption datasets for the cities of Abidjan (Ivory Coast), Cotonou (Benin) and Lomé (Togo) for the 1990-2015, 2000-2015 and 2008-2014 periods respectively were collected from national electricity companies, and meteorological data of the synoptic stations were used to compute Cooling Degree-Days in the three cities. The Cooling Degree-Days indices were estimated using air temperature and two temperature indices (the Humidex and the Heat Index). For the statistical analysis, classical multiplicative decomposition was applied to consumption data for subperiods for which consumption was considered to show relatively homogeneous evolutionary behavior (Abidjan and Lomé from 2011 to 2014 and Cotonou from 2009 to 2014). Regardless of the temperature indices considered in the three cities, the Cooling Degree-Days indices are well correlated with the seasonal variability of power consumption and particularly, the peak consumption observed in March and the lower consumption in August. Slightly better correlations are obtained for Cotonou and Abidjan when the heat index (combining both temperature and relative humidity) are used to calculate the Cooling Degree-Days. [ABSTRACT FROM AUTHOR]

The electric-field-enhanced effect of permittivity is one of the most important physical properties of KTa1-xNbxO3 in paraelectric, thus greatly affecting the performance of electro-optic modulator and deflector. We studied the temperature dependence of the electric-field-enhanced effect and the effect of supercooling on it. We found that this enhanced effect is closely related to the Fröhlich entropy, with a minimum value that corresponds to the strongest field enhancement effect. We further discovered that supercooling could improve the field-enhanced effect by 15%, because of the small polar nanoregion (PNR) size and high polarization. In addition, we propose a novel model to describe the electric-field-enhanced characteristic of the permittivity. The model can well explain the enhanced permittivity under DC electric field and reveal that the field enhancement of permittivity is mainly caused by reorientation of PNRs gradually activated by the DC electric field. [ABSTRACT FROM AUTHOR]

Nanochanneled silicon targets with high positron/positronium (Ps) conversion rate and efficient Ps cooling were produced. Morphological parameters of the nanochannels, such as their diameter and length, were adjusted to get a large fraction of thermalized Ps at room temperature being emitted into vacuum. Ps cooling measurements were conducted combining single-shot positron annihilation lifetime spectroscopy and Doppler spectroscopy of the 13S → 23P transition. 2γ–3γ annihilation ratio measurements were also performed to estimate the positron/Ps conversion efficiency. In a converter with nanochannel diameter of 7–10 nm and depth of 3.89 μm, ∼28% of implanted positrons with an energy of 3.3 keV was found to be emitted as Ps with a transverse kinetic energy of 11 ± 2 meV. The reduction of the nanochannels depth to 1.13 μm, without changing the nanochannel diameter, was found to result in a less efficient cooling, highlighting the presence of Ps reflection from the bottom end of nanochannels. [ABSTRACT FROM AUTHOR]

The electrocaloric (EC) effect is promising for the next-generation solid-state refrigeration, yet it is difficult to improve the EC response near room temperature with either the positive electrocaloric (PEC) or negative electrocaloric (NEC) effect alone. In this work, we propose and demonstrate a strategy that achieves the coexistence of PEC and NEC effects near room temperature via electric-field-induced ferroelectric–ferroelectric phase transition in Ba(ZrxTi1−x)O3 solid solutions, while the PEC effect is generally found around paraelectric–ferroelectric transition and the NEC effect is around ferroelectric–antiferroelectric phase boundaries. Utilizing such a coexistence of PEC and NEC effects, we propose a prototype two-stage cooling device, wherein both the EC cooling temperature change and efficiency are higher than its counterpart with only the PEC or NEC effect, offering a new pathway for EC cooling in practical applications near room temperature. [ABSTRACT FROM AUTHOR]

The lifetime evaluation is strongly influenced by the measurement accuracy of the junction temperature with the Vce(T) method during power cycling test (PCT). However, the measurement delay time tmd, the time between which the load current is switched off and the test pulse is applied, induces a maximum junction-temperature offset ΔTjm. The JEDEC suggested square root t method is found only to be suitable for devices with surface-close heat generation and will induce errors for other devices such as IGBTs. In this article, two novel methods, the simulated ΔZth and the Cauer thermal model, are proposed. The principle and accuracy of these two methods are discussed in detail. Furthermore, the measured Zth curve, or the Foster thermal model method, is proven not suitable for the correction of the maximum junction-temperature offset, as it will induce the same error as the square root t method. [ABSTRACT FROM AUTHOR]

In this article, a water-cooled structure with water-cooled plates between the primary double-layer windings field of the primary structure under short-term high overload conditions and periodic operations is calculated. Second, the heat dissipation effects of two different waterway topologies are designed and compared. Based on the thermal network analysis model and multiphysical field coupling model, the heat dissipation effect of the water-cooled motor is obtained. In order to obtain the maximum sustainable working current that the motor can withstand under water-cooled conditions, a fast calculation model—response surface model—is established and the electromagnetic performance of the water-cooled motor is obtained. The analysis results show that the temperature rise of the water-cooled motor decreases greatly, and the average thrust increases by 2.73 times. Finally, the calculated and tested results of the prototype are compared and analyzed. [ABSTRACT FROM AUTHOR]

The blast furnace (BF) wall temperature field plays a key role in determining whether the operation of the BF is efficient. However, it cannot be measured directly because the BF is an enclosed complex reactor with an extremely harsh environment. To cope with this problem, a soft sensor modeling strategy of the BF wall temperature field based on a novel temporal–spatial dimensional finite-element extrapolation algorithm (TS-FEEA) is designed. A 3-D transient heat conduction model of the BF wall is first established, which considers the layered physical structure of the BF. The large volume of the BF wall causes great calculation burden when solving the 3-D transient heat conduction model of the BF wall, to solve this problem, a TS-FEEA is proposed that realizes a high-speed and accurate model numerical solution. To further improve the 3-D model precision, the measured thermocouple temperatures in the cooling stave are served as the judgment criteria, and a correction strategy for inner wall temperature is finally designed to correct the assumed inner wall temperature through multiple iterations. Simulation results demonstrate the validity of the soft sensor modeling strategy and its applicability in industrial plants. The research achievements provide valuable reference information for the BF operators to judge the furnace conditions and adjust the operation parameters. [ABSTRACT FROM AUTHOR]

A vessel containing a classical non-relativistic ideal gas is studied, which has a small hole. Gas effuses through this hole, but the hole is so tiny that the gas inside the vessel remains homogeneous. The density and the temperature of the gas inside the vessel are obtained as functions of time. [ABSTRACT FROM AUTHOR]