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Thermal comfort is crucial for indoor environmental quality, impacting occupant well-being and intellectual productivity. Despite the widespread use of HVAC technologies in residential and commercial buildings, there is growing awareness of thermal comfort, leading to more studies on this issue. According to international publication indexes nearly 60% of publications belongs to the categories of construction building technology, energy fuels, and civil engineering. It should also be noted that 40% of world energy consumption pertains to construction sector. In this context, radiant cooling and heating systems come forward with their low exergy destruction rates pointing out the potential to be energy-efficient due to their higher and lower operation temperatures. Displacement ventilation, with its low heating and cooling capacity, has not gained widespread preference. However, the increasing consciousness of global warming and energy efficiency, along with the fear of airborne virus contamination, views stand-alone or hybrid applications of radiant heating/cooling and displacement ventilation as potential future solutions. This review study investigates the impact of radiant heating/cooling and ventilation types, mixing, and displacement on thermal comfort performance, focusing on factors affecting thermal comfort in trending radiant cooling and heating applications like radiant walls, ceilings, and floors. The study emphasizes the importance of considering occupant preferences, building characteristics, and energy efficiency when choosing the most suitable heating and cooling systems for different indoor environments. Stand-alone and hybrid applications of radiant heating/cooling and displacement systems can enhance thermal comfort performance, with the exception of specific cases requiring a high thermal load or ventilation rate. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing (WAAM) is a notable process in metal additive manufacturing (MAM) for the fabrication of metal parts that utilizes economically viable equipment and has high productivity compared to other MAM processes. However, excessive heat accumulation during metal deposition and the cooling method can induce residual tensile stresses and the emergence of defects, which can compromise the geometrical and mechanical integrity of components produced by WAAM. A relatively effective solution to reduce the occurrence of defects and increase the production of high-quality, structurally reliable parts with better surface finishes is to implement temperature control between passes in the WAAM process. This work is aimed at implementing and evaluating active cooling techniques using forced air cooling system (FACS) and half-immersion cooling system (HICS) in WAAM. For this purpose, FACS and HICS systems were implemented and WAAM preforms were produced under different cooling conditions. Visual inspection and geometric and microhardness characterization of the obtained preforms were performed, as well as productivity analysis of the system. The results of the geometric evaluation show little discrepancy between the dimensions of the preforms produced with different cooling techniques, with significant reductions in manufacturing time using FACS and HICS compared to natural cooling (NC), by approximately 73.1% and 87.1%, respectively. Similarly, the impact of the cooling mode on the formation of porosities is discernible. When the FACS system is employed, these defects are more susceptible to generation. The transverse hardness profiles of the three preforms exhibited comparable trends along the manufacturing direction. However, the manufactured system used by HICS exhibited higher average hardness values. [ABSTRACT FROM AUTHOR]

Heating or cooling systems are of high demand in many industries. Both types of systems are dependent on the geometry. We characterized the CuO-water nanofluid flow, heat and mass transfer through a horizontal channel when additionally heated through the center. The heat is transferred from the cylinder present along the flow. The velocity slip, thermal and diffusion slip effects on the cylinder are studied. The transverse magnetic field is also applied. The Galerkin finite element method is applied to solve the coupled nonlinear governing equations. The results are presented using stream plots and contour plots. The rate of heat transfer is calculated.30% increase in heat transfer rate is observed when the thermophoresis is doubled. Interestingly heat transfer rate is reduced by 40% when the thermal slip is doubled. So the thermal slip is more useful to include in heating or cooling systems as per the industrial need. [ABSTRACT FROM AUTHOR]

With buildings representing a substantial portion of global energy consumption, exploring alternatives to traditional fossil fuel-based heating and cooling systems is critical. Thermoelectricity offers a promising solution by converting temperature differentials into electrical voltage or vice versa, enabling efficient indoor thermal regulation. This paper presents a comprehensive investigation into the integration of thermoelectric wall systems for sustainable building climate control through numerical simulations and experimental analyses. Numerical simulations using computational fluid dynamics (CFD) techniques were conducted to model fluid flow and heat transfer within the thermoelectric wall systems under various operating conditions. These simulations provided insights into the system's thermal behavior, which were validated through experimental setups designed to measure temperature differentials, airflow rates, and power consumption. The results showed that power consumption is directly correlated with electrical current, ranging from 0.19 W to 77.4 W as the current increased from 0.1 A to 2 A. Additionally, the heat absorbed by the system increased significantly with electrical current, by 706–1044%, depending on the air velocity. The thermal energy released from the hot side of the thermoelectric modules also rose substantially, ranging from 9850 to 5285% with increasing electrical current, and from 275 to 51% with higher air velocities. Moreover, increasing air velocity led to a 6.78–9.37% reduction in power consumption for currents between 0.1 A and 2 A. The coefficient of performance (COP) analysis revealed that optimizing both electrical current and air velocity is essential for maximizing system efficiency. While fan power consumption reduces COP at higher air velocities, neglecting fan power consumption results in COP improvements ranging from 6.5 × 10⁻⁴ to 49.0%. These findings highlight the potential of thermoelectric wall systems to enhance indoor comfort and energy efficiency in buildings. [ABSTRACT FROM AUTHOR]

COSINUS will be among the first underground experiments to operate Transition Edge Sensors in a dry dilution refrigerator, measuring temperature changes on the order of μ K. A pulse tube cryocooler is used to cool down to 3K, trading simplified handling, by not using liquid noble gases, for an increased vibration noise level in the acoustic frequency range. As the signals measured with a TES are in the same frequency region, it is necessary to decouple the detectors from all possible noise sources. In COSINUS, a two-level passive decoupling system was developed and tested using piezo-based accelerometers. At the first level, the refrigerator is mechanically isolated from all external noise sources. For the second level an internal spring-based system was developed and tested on a mockup system. On the first level a reduction of the vibrational background up to a factor 4 below 10 Hz could be measured. On the second level a resonance frequency of 1.2 Hz with damping of higher frequencies was achieved. [ABSTRACT FROM AUTHOR]

A digital twin-driven lifecycle management method is proposed to monitor the lifespan of motorized spindle. The lifecycle management system is designed and developed based on the combined programming of MATLAB, ANSYS, and LabVIEW. The prediction models of lifespan are built according to the digital twin (DT) data of thermal characteristics of the motorized spindle. The DT for thermal characteristics is realized through correcting the thermal boundary conditions according to the correction models which are established according to the measured and simulated temperatures at thermal key points. The temperature domain and threshold models of the cooling channel are constructed using the exponential fitting method to monitor the working status of the cooling system. The experimental results show that the DT-driven lifecycle management system can effectively monitor the status and remaining useful life of the motorized spindle, which provides a basis for the lifecycle management of the motorized spindle. [ABSTRACT FROM AUTHOR]

For a photovoltaic module coupled with thermoelectric generator, a unique wavy cooling channel is proposed, and its performance is numerically assessed by using three-dimensional computations. The cooling channel uses nanofluid of alumina–water with various shaped nanoparticles (spherical, cylindrical and brick). Numerical simulations are performed for a range of parameters for the corrugation amplitude ( 0 ≤ Amp ≤ 0.1 ), wave frequency ( 2 ≤ Nf ≤ 16 ), nanoparticle loading quantity ( 0 ≤ SVF ≤ 0.03 ), and nanoparticle shape (spherical, brick, and cylindrical). We analyze the photovoltaic module's average temperature and temperature uniformity for a variety of parameter variations. When nanofluid and greater channel corrugation amplitudes are utilized, the average panel surface temperature is decreased more. A wavy shape of the cooling channel at the maximum corrugation amplitude yields a cell temperature reduction of 1.88 o C, while frequency has little impact on average cell temperature and its uniformity. The best-performing particles are those with cylindrical shapes, and the drop-in average photovoltaic temperature with solid volume fraction is essentially linear. As utilizing cylindrical-shaped particles, the average temperature of corrugated cooling channels decreases by around 1.9 o C as compared to flat cooling channels with base fluid at the greatest solid volume fraction. As compared to un-cooled photovoltaic, cell temperature drops by around 43.2 o C when employing thermoelectric generator. However, temperature drop value of 59.8 o C can be obtained by using thermoelectric generator and nano-enhanced wavy cooling channel utilizing cylindrical-shaped nanoparticles. An hybrid computational strategy for the fully coupled system of photovoltaic with cooling system is provided, which reduces the computational time by a factor of 75. [ABSTRACT FROM AUTHOR]

The design integration of absorption and adsorption cooling systems is a recently emerging research field in which the inherent advantages of both these systems are intended to be combined so as to maximize system performance. However, a vast majority of the conventional integration approaches reported in the literature still suffer from the following drawbacks: (a) the inability to provide a continuous cooling effect of the integrated design during the switching period of the adsorption component, (b) the lack of incorporation of the mass/heat recovery cycles and its subsequent effects upon the integrated performance, and (c) the lack of functional dependence of all thermodynamic variables including heat capacities and adsorption enthalpy upon operational parameters such as temperature and pressure. This study presents the first attempt of a numerically validated performance prediction of such an integrated system with parallel functionality to facilitate a continuous cooling operation. An empirical model of mass recovery cycle has been formulated for the very first time which adequately describes the sorption dynamics during mass transfer. All thermodynamic variables have been expressed as functions of operational parameters during the cooling cycle. For a mean driving temperature predicted to be as low as 38 °C and a mean cycle time of 11.82 min, the proposed integrated design has been predicted to yield a cycle-averaged specific cooling power of 48.93 W kg−1 and a minimum achievable coefficient of performance of 0.74 compared to the corresponding values of 27.64 W kg−1 and 0.57 for the benchmark stand-alone silica gel/water adsorption chiller. [ABSTRACT FROM AUTHOR]

The conformal cooling channel is more and more favored by the mold enterprises because of its excellent cooling performance. However, the current design of conformal cooling channel generally has the problems of complex, time-consuming, and error prone design process. The spiral cooling channel is a very important cooling channel structure in injection mold, and its application is extremely common in practical mold engineering cases. For a long time, designers have had to rely on manual construction of spiral cooling channel, which is a cumbersome and inefficient design process. Inspired by the spring structure and based on the design characteristics of spiral cooling channel, this paper puts forward an automatic generation method of conformal cooling channel based on the basic requirements of conformal cooling channel design in engineering practice. The basic idea of this method firstly is to generate the initial trajectory lines and store them in a list in the specified order. Then, based on the initial trajectory line as the basic geometry, a series of control points are generated, and all control points, including the inlet and outlet coordinate points, are sorted. Finally, generate a spline curve based on the control points and scan along the spline curve with the specified cross-section to form cooling channels. Experimental results show that this method can significantly decrease the time of design and guide users to quickly complete the design, while reducing design errors to improve working efficiency. [ABSTRACT FROM AUTHOR]

A thermoelectric cooling and thermal control system for electronic devices is considered. Based on a mathematical model using the operating characteristics of a serial thermoelectric module as the initial data, the energy characteristics of a thermoelectric cooling system are calculated, taking into account its thermal resistances. The calculation results are presented in the form of diagrams, which allow for a coordinated selection of the system's thermal resistances, ensuring the specified values of the cooling capacity and temperature difference. [ABSTRACT FROM AUTHOR]

This study examines the efficiency of a microprocessor's cooling system and maintaining the optimal temperature of electronic components. To do this, experiments are carried out on the existing cooling system of the microprocessor with control of all main parameters, primarily such as the temperature and coolant flow, as well as the performance and temperature of the processor. Based on the data obtained, a mathematical model is built that describes the change in the microprocessor's power and allows us to calculate the temperatures and speeds of coolants, as well as obtain the most effective modes for the operation of the cooling system. The obtained experimental data and mathematical model make it possible to predict the required power of the cooling system and the operating parameters of microelectronic components, which is especially important when new generations of microprocessors with the highest performance appear. The data obtained also makes it possible to calculate parameters for existing processors in order to maximize the efficiency and reliability of their operation, which is also relevant for other electronic devices, in particular microcontrollers. [ABSTRACT FROM AUTHOR]

With the continuous advancements in electronics towards downsizing and integration, efficient thermal dissipation from chips has emerged as a critical factor affecting their lifespan and operational efficiency. The fan-less chip cooling system has two critical interfaces for thermal transport, which are the contact interface between the base and the chip dominated by thermal conduction, and the surface of the fins dominated by thermal radiation. The different thermal transfer modes of these two critical interfaces pose different requirements for thermal management materials. In the study, a novel approach was proposed by developing graphene thermal transport functional material whose morphology could be intentionally designed via reformed plasma-enhanced chemical vapor deposition (PECVD) methods to meet the diverse requirements of heat transfer properties. Specifically, graphene with multilevel branching structure of vertical graphene (BVG) was fabricated through the hydrogen-assisted PECVD (H2-PECVD) strategy, which contributed a high emissivity of ∼ 0.98. BVG was deposited on the fins' surface and functioned as the radiation enhanced layer to facilitate the rapid radiation of heat from the heat sinks into the surrounding air. Meanwhile, the well-oriented vertical graphene (OVG) was successfully prepared through the vertical electric field-assisted PECVD process (EF-PECVD), which showed a high directional thermal conductivity of ∼ 53.5 W·m−1·K−1. OVG was deposited on the contact interface and functioned as the thermal conduction enhanced layer, allowing for the quick transmission of heat from the chip to the heat sink. Utilizing this design concept, the two critical interfaces in the chip cooling system can be jointly enhanced, resulting in a remarkable cooling efficiency enhancement of ∼ 30.7%, demonstrating that this novel material possessed enormous potential for enhancing the performance of cooling systems. Therefore, this research not only provided new design concepts for the cooling system of electronic devices but also opened up new avenues for the application of graphene materials in thermal management. [ABSTRACT FROM AUTHOR]

A solid desiccant-based novel dehumidification technique in indoor cooling is a viable substitute for a traditional dehumidification system in regions with high humidity levels. The ozone layer is being steadily destroyed by vapour compression-based conventional dehumidification systems, which also have a number of other disadvantages such as excessive power consumption and a rise in the amount of chlorofluorocarbons type refrigerant leakage in the atmosphere. As compared to traditionally used vapour compression type refrigeration air conditioners, solid desiccant-integrated novel cooling may be more advantageous as it provides more easily accessible, cost-effective, and ecologically sound cooling. It can be more competitive when it is reactivated by freely available renewable heat available from solar power and industrial waste heat. Not only marginally saving energy, but it can also help in drastically lower operational costs. Recently, many studies have been carried out with aim of ameliorating desiccant air conditioners' overall performance through the development of novel system configurations, enhanced system designs and better controls, and the integration of hybrid energy sources for desiccant reactivation as well as sub-systems technological advancements. By this means, the present study offers a thorough analysis of the previously described investigations. This offers detailed study on possible suggestions and recommendations for possible future work direction based on the most recent investigations in the field of the desiccant-powered novel cooling techniques. These recommendations can help to amplify the efforts to find better solutions to concurrent technological issues, which will definitely ameliorate the overall performance of desiccant-integrated dehumidification and hybrid cooling in the field of heating, ventilation and air conditioning. [ABSTRACT FROM AUTHOR]

Vaccines are one of the most effective methods used to prevent many lethal and infectious diseases from past to present. Generally, storage temperatures of vaccines are between 2 and 8 °C. Keeping the vaccines in this temperature range and ensuring reach the end user without deterioration is very important in order to prevent the vaccines from losing their effectiveness. In this regard, various cooling systems are used. One of the devices used to ensure the cold storage of vaccines is a thermoelectric device. Thermoelectric devices attract attention as an energy-efficient technology, as well as their compact structure, silent and vibration-free operation, and suitability for automation. In this study, the design and manufacturing of a photovoltaic solar energy-driven, nanofluid-integrated thermoelectric vaccine cabinet was carried out and its performance data were experimentally examined. The capacity of the vaccine cabinet is 200 vaccine vials and 200 ready-to-use syringes, as well as the battery and inverter parts. In experiments carried out at two different outdoor temperatures, heat removal from the hot surface of the thermoelectric cooler with different refrigerants were examined. In addition, the effects of using fans were also investigated while the heat swept from the surface was transferred to the environment with the help of a water-to-air heat exchanger. In the experiments carried out for a total of 8 different cases, the highest average coefficient of performance value obtained during the experiments was 1.19. Experimental results show that vaccine storage temperatures can be reached under the prepared operating conditions. [ABSTRACT FROM AUTHOR]

Magnetic nanofluids have gained significant attention in recent years due to their unique properties and potential applications in various fields. This review paper provides an in-depth analysis of the utilization of magnetic nanofluids in thermal applications. Article presents a comprehensive overview of the various synthesis methods of magnetic nanofluids and key properties of magnetic nanofluids. The thermal stability of magnetic nanofluids is also highlighted in this review. Additionally, various thermal applications of magnetic nanofluids, such as cooling systems, heat exchangers, and thermal energy storage, solar systems are explored along with their potential benefits and challenges. Finally, future research directions and prospects for magnetic nanofluids in thermal applications are highlighted. [ABSTRACT FROM AUTHOR]

In this paper, a neuro-adaptive PI control strategy for a water-cooled centrifugal chiller system is developed, and its control performance is examined. The system model consists of a flooded evaporator, a flooded condenser, a centrifugal compressor, and an electronic expansion valve. The overall system consists of three control loops: a compressor speed control loop, an inlet guide vane (IGV) control loop, and a condenser liquid level control loop. A neuro-adaptive control strategy for compressor speed control was designed. The control performance of the chiller was tested by carrying out simulation runs using an integrated building and HVAC (IB-HVAC) system model. The major details of the IB-HVAC model are described in this paper. Results show that the neuro-adaptive controller can adapt to new system dynamics of the IB-HVAC system and give good setpoint tracking responses under a wide range of operating conditions. The results show that the neuro-adaptive controller performs better than the constant gain PI controller in terms of speed of response and setpoint tracking properties. [ABSTRACT FROM AUTHOR]

With the increasing demand for heat dissipation of engineering vehicles, a dual-cycle cooling system is introduced in this paper to prevent the adverse effects of engineering vehicles' equipment when operating at the overheating temperature. The performance of the new system is analyzed through tests, and the results show that the dual-cycle cooling system can meet the thermal balance requirements of the engineering vehicle during the shovel operation. Compared with the traditional cooling system, the new cooling system improved performance in terms of volume, engine energy consumption and working oil efficiency. The oil consumption of a wheel loader using the dual-cycle cooling system is reduced by 1% per hour, and the temperature of its transmission oil and hydraulic oil is reduced by more than 10 °C. The new cooling system has bright future in energy saving and emission reduction of engineering vehicles. [ABSTRACT FROM AUTHOR]

The incorporation of conformal cooling systems has significantly enhanced the efficiency and quality of injection molding process. While several automated methods have been developed for creating conformal cooling channels in injection molds, the current optimization process for conformal cooling design parameters is hindered by labor-intensive iterative thermal simulation processes and the substantial reliance on empirical human knowledge. This paper presents an innovative machine learning method to assess the thermal performance of conformal cooling systems by employing a combination of a non-linear regression model and a neural network. By employing a logarithmic regression model describing the temperature graph and a neural network predicting the coefficients of the logarithmic regression model, the thermal performance of specified conformal cooling systems can be assessed and predicted precisely. This methodology empowers designers to evaluate the thermal efficiency of conformal cooling systems efficiently and effectively to further optimize the conformal cooling design parameters without relying on tedious manual thermal and fluid simulation processes. [ABSTRACT FROM AUTHOR]

For the first time pilot castings of an aluminum alloy into a patented mold with an evaporative-condensation cooling system are carried out with extraction of the resulting cylindrical billet obtained with a diameter of 62 mm. It is shown that the flow rate of cooling water to a mold may be reduced by a factor of 2–3 by increasing the temperature of the water leaving the condenser to t = 60–80 °C. Adjustments are made to the design calculation of wall temperatures, taking into account preliminary heating of the crystallizer and experimental values of temperatures. The state of the surface of the workpieces obtained is analyzed in two pouring modes. Calculation and comparison of heat supplied to and removed from the mold, and thickness of a billet skin are performed. [ABSTRACT FROM AUTHOR]

Phase Change Materials (PCMs) have got widespread attention in thermal energy storage (TES) applications as a result of their wide operational temperature range, high energy storage density, and prolonged life cycle at a reasonable cost. They offer a practical solution to mitigate the building energy consumption, addressing interior temperature fluctuations and enhancing demand-side management through the incorporation of renewable energy and off-peak power. This study focuses on evaluating the influence of PCMs on the performance of radiant heating and cooling systems. Based on conducting a comprehensive review, this study explores the current challenges associated with PCM utilization in these systems. The analysis discloses noteworthy discoveries and potential advantages, paving the way for further investigation and wider adoption of PCMs in the construction industry. Notably, the incorporation of a 10-mm PCM resulted in a 2.4% annual reduction in heating energy consumption in comparison with the existing structures. Furthermore, utilizing a 20–50-mm PCM could yield annual heating energy savings ranging from 7.3 to 15.3%. N-eicosane emerges as the most effective PCM for floor heating, achieving an optimal floor temperature and contributing to a substantial 43% reduction in heating energy consumption. Ultimately, radiant floor systems demonstrate the potential to reduce energy consumption by up to 8% and 4% in a comparison with commercial heating and cooling systems, respectively. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive thermodynamic analysis was performed to evaluate and optimize the performance of a solar-powered single-effect lithium bromide-water absorption chiller system. A computational model was developed to systematically investigate various design parameters, including the impact of inlet generator, absorber/condenser, and evaporator temperatures on the system's energy and exergy efficiency. Additionally, the study evaluated the influence of solution heat exchanger effectiveness and hot source temperatures. Key performance indicators such as cooling production capacity, coefficient of performance, exergy efficiency, and overall solar cooling system efficiency were considered. The results indicated that a condenser/absorber temperature of 30 ℃ improved the coefficient of performance to 0.8, and the cooling capacity to 30.05 kW while varying the evaporation temperature between 4.5 to 10.5 ℃ improves the coefficient of performance by approximately 10.38%. Increasing the solution heat exchanger effectiveness resulted in a 16.77 and 16.076% enhancement for both the coefficient of performance and exergy efficiency, with generator temperatures of 74 and 90 ℃. The system achieves its highest performance within a hot source temperature range of 70–75/ ℃. Proper selection of heat exchanger temperatures significantly improved the performance of the absorption subsystem. The intensity of solar irradiance and ambient conditions influenced the system's efficiency. [ABSTRACT FROM AUTHOR]

In this work, a new solar cooling system that is powered by a concentrated photovoltaic thermal module is presented. Given the intermittent nature of solar energy, the essence of this system lies in its capability to offer continuous cooling. Furthermore, the proposed cooling system is versatile in operation, with three alternative modes available depending on the user's demands. Two operating scenarios of the system are presented. In the first scenario, thermal energy is utilized for cooling during the daytime, while electric energy is stored as compressed air for nighttime use. In the second scenario, both thermal and electric energies are employed for cooling during periods of high demand. The system is studied under different evaporator temperatures, various ambient temperatures, and different solar intensities. The results show that at an evaporation temperature of 4 °C, the system can provide continuous cooling, generating up to 10.24 kW of cooling power during the daytime and up to 7.66 kW during the nighttime, with an overall coefficient of performance of 0.612. [ABSTRACT FROM AUTHOR]

In this paper, three photovoltaic (PV) cooling systems are examined. The three cooling systems are (1) a PV frontside passive air (FPA) cooling system that relies on the chimney effect of air to cool the PV module, (2) a PV frontside active water (FAW) cooling where water flows in frontside of the PV panel, and (3) a PV backside active water (BAW) cooling system where water flows in a heatsink (collector) attached to the backside of the PV module. While comparing to the standalone PV, the FPA, FAW and BAW systems have cooled the PV surface temperature by 2.1, 22.4 and 17.8 °C, respectively. The FPA and BAW systems improved the PV electric efficiency by 0.84 and 6.86%, respectively; while, the FAW system degraded the PV efficiency by 26.27 % . The spectrometer measurement showed that the plexiglass and water thickness significantly lower the transmission of ultraviolet and visible light waves to the PV module. In contrast, the FAW system produced water with higher thermal content than that of the BAW system. The results show that to maximize electrical power output, BAW system is recommended, while to maximize thermal energy collection, FAW system is recommended. [ABSTRACT FROM AUTHOR]

An analysis of various system configurations of hydrogen refueling stations and the types of failures that can occur in these stations is presented herein. Although the major components (compressor, storage tank, dispenser and chiller) are the same across various configurations, the numbers of compressors and storage tanks, as well as the system layouts, are different. Because compressors are operated at high pressure, leakage from valves and malfunctioning of lubricant oil pumps occur frequently (−50 % of all failures). Moreover, because hydrogen gas at −40 °C flows through the dispenser, the receptacle at the inlet of the storage cylinder can freeze, and leakage of cold refrigerant from the chiller system occurs frequently (both account for −20 % of all failures). Periodic maintenance of pipes and valves, compressor, and dispenser should be performed to pre-vent leakages and compressor malfunction. The outcomes of this study can help improve the economic feasibility of hydrogen refueling stations. [ABSTRACT FROM AUTHOR]

In this study, we present a new mixed cooling system that combines internal oil with water-cooling, and the effective temperature control of the motor resulted in long-term stable operating conditions. Mass, momentum, and energy equations were obtained by adopting the volume of fluid and moving reference frame methods for an in-depth heat transfer analysis of motor cooling systems. In addition, various cooling systems, such as churning and drop methods were carefully selected by considering the maximum temperature and heat transfer path of the advanced motor. To ensure the reliability of the computational model, the internal thermal resistance of the motor was adjusted based on the analysis results of the reference case. The churning effect facilitated heat transfer through the air gap, thus minimizing the local temperature difference between the rotor magnets and stator coils. The drop effect directly cooled the end coil, thereby resulting in a high cooling efficiency. [ABSTRACT FROM AUTHOR]

A hybrid cooling tower, which is a promising type of coolers, can be used successfully to cool the circulating water of industrial enterprises taking into account the modern requirements for energy efficiency, resource saving, and environmental friendliness. A hybrid cooling tower design has been developed including a sprinkler made of inclined corrugated contact elements and an internal finned tubular radiator. The purpose of the work is to experimentally determine the volumetric coefficients of heat and mass emission in the developed hybrid cooling tower for cooling circulating water. A diagram of an experimental installation of a cooling tower with hybrid cooling system is presented and described. Graphic dependences were constructed for the volumetric coefficients of mass emission and heat emission on the average flow rate of cooling air at various wetting mass densities. A dimensionless equation has been obtained for determining the volumetric coefficients of mass emission in a hybrid cooling tower with transverse finning of radiator pipes. A comparison of volumetric coefficients of mass emission for the developed cooling tower with other water-cooling devices showed the potential of its usage for cooling circulating water, especially at high ratios of gas and liquid phase loads. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of a water sprinkler cooling system for a centrifugal Babbitt lining machine, used to renovate industrial bearings. A three-dimensional and transient numerical simulation was conducted to study the effects of various parameters on the solidification rate, including mold rotational speed, sprinkler flow rate and angle, and initial temperatures of the mold and Babbitt alloy. Results demonstrate that the temperature drop in the Babbitt layer and mold is directly proportional to the rotational speed, with a 15% change in rotational speed from the reference case resulting in a 5 °C change in the average temperature of the Babbitt alloy, while clockwise (CW) rotation of the mold leads to greater temperature reduction. An optimal rotational speed of 550 rpm CW was determined. The study also identified an optimal total water flow rate of 8.7e−5 m3/s, with minimal additional cooling benefits beyond that point. Furthermore, vertical water sprinkler angles were found to provide superior cooling performance. The initial mold temperature was found to have a more significant influence on the final average Babbitt temperature than the initial Babbitt temperature, due to the mold's larger mass and thermal inertia. The qualitative and quantitative results of this research offer valuable insights for enhancing the design of water sprinkler cooling systems in centrifugal Babbitt lining machines, providing a pathway for transitioning from manual to automated cooling processes. This innovative approach has the potential to transform industries in underdeveloped countries, improving their efficiency, quality, and safety. [ABSTRACT FROM AUTHOR]

Effective cooling systems for injection moulding (IM) tools are critical to reducing manufacturing costs and cycle time for the polymer parts produced. This work presents a novel automated methodology for designing conformal cooling channels (CCCs) for IM tools via interlinking commercial moulding simulation tools with custom scripts. These scripts adjust CCC design in response to the spatial variability in global and local temperatures at the mould tool-part interface (MTPI) via generative design (GD). Four tool designs for manufacturing a simplified part were analysed numerically simulation and experimentally, including tools with either straight-drilled (non-conformal) cooling channels (tool steel), a manually designed CCC system (stainless steel or bronze alloy), or an automatically designed CCC system (stainless steel). While both manually designed CCC tools cool the part faster than the non-conformal tool (3–5% predicted vs. 40% measured for stainless steel and 9–12% predicted vs. 40% measured for bronze alloy), the GD-optimised CCC tool outperformed both (15–30% predicted faster cooling vs. 70% measured). The predicted MTPI temperature feature achieves reductions to both maximum and spatial variability in MTPI temperatures, which lead directly to significant reductions in manufacturing cycle time and polymer part warpage. These findings could have a major impact on the IM industry by reducing tool design costs and raw material waste via improving moulded part quality. [ABSTRACT FROM AUTHOR]

Desalination, which converts saline water into freshwater, has been proposed as a possible alternative to address the worldwide freshwater scarcity problem. The humidification–dehumidification (H–DH) desalination technique can provide appropriate quantity of freshwater to the population residing in water-stressed regions. The aim of the current study is to investigate the solar H–DH desalination system performance which consists of a solar air heater based on double-ends open evacuated tube collector, a packed bed humidifier, and a dehumidifier. The packing material used in humidifier is aspen pads. The performance is assessed based on system overall efficacy, gained output ratio (GOR), yield, and efficacy of humidifier and dehumidifier at three distinct process air flow rates. The average overall system efficacy, yield, and GOR are 11.97%, 4.1 kg day-1, and 0.84, respectively, for open-loop system. The closed-loop system reports better performance at low mass flow rate. The average overall system efficiency, daily yield, and GOR at 100 kg h−1 are 32.48%, 11.9 kg day-1, and 2.44, respectively, for a closed-loop system. [ABSTRACT FROM AUTHOR]

The cooling systems contribute to 40% of overall building energy consumption. Out of which, 40% is wasted because of faulty parts that cause anomalies in the cooling systems. We propose a three-stage, non-invasive part-level anomaly detection technique to identify anomalies in both cooling systems, a ducted-centralized and a ductless-split. We use COTS sensors to monitor temperature and energy without invading the cooling system. After identifying the anomalies, we find the cause of the anomaly. Based on the anomaly, the solution recommends a fix. If there is a technical fault, our proposed technique informs the technician regarding the faulty part, reducing the cost and time needed to repair it. In the first stage, we propose a domain-inspired time-series statistical technique to identify anomalies in cooling systems. We observe an AUC-ROC score of more than 0.93 in simulation and experimentation. In the second stage, we propose using a rule-based technique to identify the cause of the anomaly. We classify causes of anomalies into three classes. We observe an AUC-ROC score of 1. Based on the anomaly classification, we identify the faulty part of the cooling system in the third stage. We use the Nearest-Neighbour Density-Based Spatial Clustering of Applications with Noise (NN-DBSCAN) algorithm with transfer learning capabilities to train the model only once, where it learns the domain knowledge using the simulated data. The trained model is used in different environmental scenarios with both types of cooling systems. The proposed algorithm shows an accuracy score of 0.82 in simulation deployment and 0.88 in experimentation. In the simulation we used both ducted-centralized and ductless-split cooling systems and in the experimentation we evaluated the solution with ductless-split cooling systems. The overall accuracy of the three-stage technique is 0.82 and 0.86 in simulation and experimentation, respectively. We observe energy savings of up to 68% in simulation and 42% during experimentation, with a reduction of ten days in the cooling system's downtime and up to 75% in repair cost. [ABSTRACT FROM AUTHOR]

Over the past two decades, extensive research has elucidated the significant contributions of various nanomaterial such as metals, metal oxides, carbon nanotubes (single, double, and multi-wall), nanowires, and graphene in improving the tribological and thermal properties of AC & R systems used in both industrial and domestic settings. A recent research paper has specifically focused on the performance enhancement of AAC through the use of Nano-oxides, namely CuO, ZnO, and TiO2, employing mathematical modeling. This study investigates how dispersed Nano-oxides of CuO, ZnO, and TiO2, when added to a base of POE lubricant and HFC-R134a refrigerant, influence the performance of automobile air conditioning systems. The primary focus is on viscosity, heat transfer rate, and thermal conductivity of the working medium. The experimental results are compared with tested data, and further analysis is conducted using TK Solver 6.0 and Origin Lab software. The findings demonstrate that the incorporation of these Nano-oxides has a positive impact on thermal-physical properties (k-Thermal conductivity, ρ-viscosity, ρ-density and Cp-specific-heat) and heat transfer characteristics compared to systems without Nano-materials. Furthermore, there is a notable increase in Coefficient of Performance (COP) ranging from 23–29% with varying volume concentrations of Nano-oxides (0.5% to 2.5%) under atmospheric temperature conditions. Consequently, the combination of copper oxide, Zinc Oxide, and Titania nanoparticles with HFC-R134a as well as R1234ze (E) proves to be an effective approach for optimizing refrigerant properties and improving the performance of automobile air conditioning systems. Thus, Nano-oxides dispersion offer a promising solution for enhancing energy efficiency and reducing the reliance on conventional energy sources in thermal systems. [ABSTRACT FROM AUTHOR]

The electric drive thermal management system of electric vehicles is an important part of electric vehicles. To improve the cooling effect of the electric drive system and reduce energy consumption, a cooling scheme combining the spray oil cooling of the motor end winding with the cooling water jacket of the motor shell and the water cooling in the motor shaft is proposed. Based on the electric drive cooling system framework of electric vehicles, a fuzzy logic control strategy is established. The flow rate and heat dissipation in the system are optimized by controlling the rotation speed of the oil/water cooling pump and the radiator fan, which further reduces the energy consumption of the system. In addition, through the co-simulation of AMESim and Simulink, under the same simulation time, the simulation comparison and analysis are carried out under SFTP-US06 and WLTC conditions, respectively. The power loss of fuzzy logic control is 9% and 28% lower than that of switching control, and 21% and 25% lower than that of PID control, respectively. [ABSTRACT FROM AUTHOR]

A method for microextraction recovery and concentration of tilmicosin phosphate in washings from surfaces of pharmaceutical equipment for its determination by high-performance liquid chromatography with spectrophotometric detection was proposed. The developed method involved dispersion of the extractant (1-dodecanol) in an aqueous solution of a sample while rotating a cotton disk equipped with an inserted magnetic stirrer followed by crystallization of the extract upon cooling the extraction system. The extractant was applied beforehand to the cotton disk. Effective dispersion of the extractant in the aqueous phase during rotation of the cotton disk ensured a high degree of analyte recovery (94%). The detection limit of tilmicosin phosphate (3σ) reached 0.7 mg/L. The determined concentrations ranged from 2 to 250 mg/L. The analytical capabilities of the developed method were demonstrated using quantitative determination of tilmicosin phosphate in washings from surfaces of pharmaceutical equipment after completion of its cleaning as examples. [ABSTRACT FROM AUTHOR]

Nanofluids are engineered materials which are basically colloidal substances prepared by the dispersion of metallic/metallic oxide nanoparticles into a suitable base fluid. The two different phases in nanofluids (solid and liquid) result in entirely different thermophysical properties from the separated phases. The properties exhibited by nanofluids have inspired the researchers to analyze them under a variety of backgrounds. The effectiveness of CuO/water nanofluids in cooling of a smartphone processor is investigated and compared to water in this work. The cross-sectional area for heat dissipation from a processor is obtained from its datasheet. In the first step, numerical analysis is done with water as the medium of heat transfer with a heat flux, and then, experiment is performed using CuO/water nanofluid as heat transfer medium for four volume fractions 0.1%, 0.2%, 0.3% and 0.4% and fluid gap thicknesses as done in the case of water. The heat transfer through nanofluid will be effective only if both the base fluid and nanofluid are in the same mode of heat transfer—either conduction or convection. The mode of heat transfer depends on a number of factors such as temperature, fluid layer thickness, nanoparticle volume fraction, etc. A numerical and experimental investigation on the impact of these parameters is done in this paper using cupric oxide–water nanofluid. It is concluded that the advantage obtained by the increased thermal conductivity of the nanofluid due to the addition of nanoparticles will be offset by the delayed convection onset resulting in a reduced overall heat transfer enhancement when compared to base fluid. Since the convection process is aided by increased temperature, a nanofluid is suitable for enhanced heat transfer under conditions of high heat flux densities and for miniaturized systems where cooling system space is a significant limitation. [ABSTRACT FROM AUTHOR]

Cryogenic qubit controllers (QCs) are the key to build large-scale superconducting quantum processors. However, developing scalable QCs is challenging because the cooling power of a dilution refrigerator is too small (~10 μW at ~10 mK) to operate conventional logic families, such as complementary metal-oxide-semiconductor logic and superconducting single-flux-quantum logic, near qubits. Here we report on a scalable QC using an ultra-low-power superconductor logic family, namely adiabatic quantum-flux-parametron (AQFP) logic. The AQFP-based QC, referred to as the AQFP-multiplexed QC (AQFP-mux QC), produces multi-tone microwave signals for qubit control with an extremely small power dissipation of 81.8 pW per qubit. Furthermore, the AQFP-mux QC adopts microwave multiplexing to reduce the number of coaxial cables for operating the entire system. As a proof of concept, we demonstrate an AQFP-mux QC chip that produces microwave signals at two output ports through microwave multiplexing and demultiplexing. Experimental results show an output power of approximately −80 dBm and on/off ratio of ~40 dB at each output port. Basic mixing operation is also demonstrated by observing sideband signals. [ABSTRACT FROM AUTHOR]

A new power and refrigeration cycle is examined in the present study. The system proposed is a combination of organic Rankine cycle (ORC) and an ejector refrigeration cycle (ERC). An ERC is introduced into the ORC to recover heat from partial expansion of the ORC fluid. The heat recovery is enhanced with the incorporation of recuperator, evaporator and superheater as heat exchangers. Among the various working fluids opted for, R245fa and R236ea have been considered in the present work. The properties of the combined cycle state points are evaluated through Engineering Equation Solver (EES) software. The impact of decision variables (such as hot source temperature, turbine expansion ratio, extraction ratio, and separator temperature) on performance parameters (such as exergy destruction, energy efficiency of power generation, exergy efficiency of power generation, energy efficiency of combined system, exergy efficiency of combined system, COP, and cooling power ratio) is examined and reported. The series heater configuration in ORC has improved system performance by recovering waste heat more effectively. At the same parametric conditions, the energy and exergy performances of R245fa are higher than those of R236ea. [ABSTRACT FROM AUTHOR]

The thermal error suppression rate depends on the cooling effect of the water cooling system, and the cooling water flow rate is a direct factor affecting the cooling effect. To better reduce the thermal error, a numerical model of cooling water is established to solve for the optimal cooling water flow rate. Firstly, a numerical model of thermal deformation of the pendulum angle milling head is established based on thermoelasticity theory to determine the main heat sources leading to thermal deformation. Then, a numerical analysis model of the cooling water flow rate is established to investigate the cooling water flow rate that has the best effect on the suppression of thermal errors. Finally, five flow rates are used for cooling experiments to verify the accuracy of the numerical model. The results show that the temperature of each measurement point increases with the flow rate from a significant decrease to the basic constant trend of gradual saturation. The reduction rate of thermal error at v=54 cm/s is as high as 73.4%, providing a theoretical basis for enterprises to optimize water cooling system parameters. [ABSTRACT FROM AUTHOR]

In this study, a hybrid absorption chiller was proposed as a part of the energy supply facility for a building with a rooftop greenhouse. Using the exhaust gas and the cooling water from the gas engine, the hybrid absorption chiller supplies the cooling and heating in summer and winter, respectively. Starting from the reference cycle, optimization processes were performed in three steps to maximize the improvements in the cooling capacity and the COP. The COP and the cooling capacity of the finally optimized cycle could be substantially improved compared to those of the initial reference cycle. Additionally, the performance characteristics in off-design conditions were investigated. The hybrid absorption cycle displayed a unique feature, that is, the overall COP decreased with the increasing temperature and the mass flow rate of the hot water due to the crucial role of the single-effect cycle with a low COP. Using the proposed hybrid absorption chiller, a COP of approximately 1.1 can be achieved, which is substantially higher than that of a single-effect absorption chiller. If the present hybrid absorption system is widely applied to places where gas- and liquid-phase waste heat is available, then this system is expected to contribute to energy savings and the reduction of CO2 emissions. [ABSTRACT FROM AUTHOR]

In this study, the thermal comfort and energy consumption of two different terminal units when combined with three different water supply temperatures were studied. Results showed that convection–radiation combined cooling terminals can increase the water supply temperature under the same thermal comfort level compared with convection cooling terminals. When the water supply temperature was fixed at 11 °C, the energy consumption of convection–radiation combined cooling terminals was 9.1 % lower than that of convection cooling terminals. The higher the water supply temperature, the lower the energy consumption under convection–radiation combined cooling terminals. Furthermore, the energy consumption rates at a water supply temperature of 15 °C were 18.2 % and 8.8 % lower than those at 7 °C and 11 °C, respectively. Meanwhile, the comfort and system operation efficiency were optimal when the water supply temperature was 15 °C, and the energy consumption was lower when combined with the cooling of the dual terminals. [ABSTRACT FROM AUTHOR]

Compared with the single-stage compression, the two-stage compression cycle shows high efficiency and application potential under both severe heating and refrigerating conditions. Therefore, to improve the performance of the two-stage vapor-compression cycle furtherly, this study introduces three ejector-assisted two-stage compression cycles (E1, E2, and E3), and a conventional two-stage vapor-compression cycles (C1) also selected as the comparison. The energetic and exergetic efficiency of the systems using various refrigerants (R152a, R1234yf, R32 and R290) is investigated and compared based on the validated theoretical model for both the severe refrigerating and heating application. The result shows that the ejector improves the system's performance significantly. Under the refrigerating mode, System E3 using R32 is recommended to be applied. Compared with Systems C1, E1, and E2, the maximum refrigerating coefficient of performance (COPR) of System E3 using R32 is improved by 16.1, 12.4, and 9.1%, respectively, with the evaporation temperature of −40 °C and condensation of 30 °C. Systems E2 and E1 using R152a are recommended under the heating mode. Compared with Systems C1 and E3, the heating coefficient of performance (COPH) of Systems E1 and E2 using R152 is improved by 3.0 and 4.5%, respectively, with the condensation temperature of 70 °C and evaporation temperature of −5 °C. The result provides a deep understanding of the potential advantages of the ejector-assisted two-stage compression cycle applied in the refrigerating and heating field. [ABSTRACT FROM AUTHOR]

Thermal errors, due to temperature rise, account for about two-thirds of the machining error of the motorized spindle. Cooling is an important means of improving the temperature properties of motorized spindles. It is important to study the effect of cooling system parameters on the temperature characteristics of the main shafts when designing the cooling system. First, we analyze the heat transfer from the motorized spindle, calculate the heat transfer coefficient, and simulate the spindle cooling system. The optimum water coolant parameters for the T-type cooling system are then obtained by analyzing the inlet and outlet temperatures of the spindle coolant, the maximum temperature of the motorized spindle system, and the radial deformation of the spindle. For the C01.10 high-speed electric spindle, the optimal cooling medium parameters for the T-type cooling system are a temperature of 20 °C and a cooling medium flow rate of 8 L/min. Finally, experiments are designed to compare experimental data with simulation data to determine the accuracy of simulation results. [ABSTRACT FROM AUTHOR]

Nuclear power plants (NPPs) use large amounts of water for cooling; recirculating cooling water systems (RCWS) take water and discharge it to the environment, concentrate natural constituents, and introduce chemicals used to maintain the chemical regime of the NPP. Changes in organic matter (OM) content can be caused by natural processes as well as human activities. The subject of the research is OM discharges with return water from RCWS NPPs. The research was carried out using the example of the RCWS Rivne NPP and the water of the Styr River, from which the Rivne NPP uses water. The relevance of the research lies in the assessment of the nonradiative environmental impact of the NPP, with the establishment of a correlation between the OM content and the technological modes of operation of the Rivne NPP. The study results show that the concentrations of the total organic carbon (TOC), the chemical oxygen demand (COD), and the 5-day biochemical oxygen demand (BOD5) are significantly related to the technological mode of operation of the RCWS of the NPP, which is determined by the concentration cycles (in the range of 1.5–5.0) using regression analysis. Therefore, the changes in OM content are correlated with the technological modes of water intake and discharge. The values of the measured environmental concentration (MEC) and the predicted environmental concentration (PEC) are comparable, and the difference between MEC and PEC does not exceed 16%. The proposed formulas were statistically tested by comparing the observed with the predicted BOD5, TOC, and COD and ranged from 27% (COD) to 6–75% (BOD5 and TOC). Moreover, according to the environmental assessment, the Styr River water in the area of influence of the Rivne NPP discharges is classified as class IV, category 6—"poor," and BOD-5–class II, category 2—"good." The novelty of the research is the multicomponent evaluation of the OM content by various indicators of TOC, COD, and BOD5 control and determination of the dynamics of their changes with the establishment of variability factors. Thus, the practical value of the study lies in the possibility of applying the methods to other power plants using RCWS. [ABSTRACT FROM AUTHOR]

Composites are driving positive developments in the automobile sector. In this study investigated the use of composite fins in radiators using computational fluid dynamics (CFD) to analyze the fluid-flow phenomenon of nanoparticles and hydrogen gas. Our world is rapidly transforming, and new technologies are leading to positive revolutions in today's society. In this study successfully analyzed the entire thermal simulation processes of the radiator, as well as the composite fin arrangements with stress efficiency rates. The study examined the velocity path, pressure variations, and temperature distribution in the radiator setup. As found that nanoparticles and composite fins provide superior thermal heat rates and results. The combination of an aluminum radiator and composite fins in future models will support the control of cooling systems in automotive applications. The final investigation statement showed a 12% improvement with nanoparticles, where the velocity was 1.61 m/s and the radiator system's pressure volume was 2.44 MPa. In the fin condition, the stress rate was 3.60 N/mm2. [ABSTRACT FROM AUTHOR]

An algorithm for estimating tritium emission during the evaporation of water from spray cooling ponds of nuclear power plants is considered. The factors determining the intensity of evaporation and intake of tritium into the atmospheric air are analyzed. For the considered meteorological and technological factors of area source operation, the intensity of tritium emission averages 6.2 Bq/h from each 1·m2 of the spray cooling pond area per each 1 Bq/L of specific water activity. The possibility of regulating the emission activity is demonstrated taking into account the data of controlled technological parameters for the water-cooling system of spray cooling ponds and the meteorological parameters of the atmosphere in the NPP location area. [ABSTRACT FROM AUTHOR]

Olivine (Fo80-88) from the Shitoukengde deposit exhibits low levels of Ca, Cr, and Al (< 220 ppm) and varying Ni content. The low Ca-Cr-Al contents in olivine and subsolidus temperatures (600–900 °C) indicated by olivine-spinel thermometers align with subsolidus equilibria, emphasizing substantial postcumulus modifications. Therefore, the postcumulus effect must be considered when applying olivine-spinel oxybarometers to intrusive rocks. Back-calculating the spinel Fe–Mg contents to magmatic temperature, the estimated oxidation fugacity (fO2) range between FQM − 1.5 and FQM − 3.0, approximately 0.5 to 1.5 ΔFQM more reduced compared to those calculated from the raw spinel composition. Moreover, the fO2 aligns with results obtained from the olivine-sulfide pair (FMQ − 3.0 to FMQ 0). The considerably reducing state and wide oxidation variation are consistent with the graphite occurrence within the reduced intervals and the systematic fO2 indicated by olivine V/Sc ratios. Combined with the wide olivine Ni range (200–1500 ppm) and the restricted Ni tenor in coexisting sulfides, those findings imply that the olivine-sulfide interaction was predominantly controlled by fO2. Diffusion modeling at magmatic temperatures reveals that the core-level Fe–Ni re-equilibration after crystallization requires hundreds of years. The homogeneous olivine composition suggests that re-equilibrium has been achieved in Shitoukengde. However, in fast cooling systems, olivine may record the status approaching olivine-sulfide equilibration, leading to extensive intragrain Ni variation (up to 1000 ppm). This study highlights that extreme Ni depletion in olivine from sulfide-bearing rocks is a sign of reducing conditions. Strongly Ni-rich olivine, such as those in the Kevitsa deposit, could result from interaction with high-Ni tenor sulfides at oxidizing conditions. [ABSTRACT FROM AUTHOR]

The utilization of cold plate radiators as a prevalent method for indirect liquid cooling has been extensively investigated and implemented in server cooling systems. However, there is a lack of comprehensive study on the application of this technology at the chip size, indicating a need for more development and exploration in this area. A proposal was made for a grid-channel chip cold plate heat sink to facilitate the dissipation of heat from a chip. tests were conducted to investigate the impact of the flow rate of the cold plate and the layout of the inlet and outlet on various thermal parameters, including the average temperature, maximum temperature, thermal resistance, and uniformity coefficient of the cold plate. The tests were specifically conducted under a chip power of 150W, and the accuracy of the simulation was confirmed through the use of FLUENT. The findings indicate that the cold plate effectively regulates the temperature of the chip, ensuring it remains below 85 °C throughout all experimental groups. In contrast to the single in single out configuration, the single-in multiple-out layout exhibits a higher degree of temperature uniformity within the cold plate. Nevertheless, it is important to note that augmenting the quantity of exits does not guarantee an improvement in heat transfer efficiency. This outcome is contingent upon the presence of a longitudinal flow channel shared by the outlet and intake, as well as the dispersion characteristics of the outlet. Enhancing the dispersion of the exit can significantly enhance the thermal transfer efficiency of the cold plate. Furthermore, a strategy for adjusting the aperture of the orifice is proposed as a solution to address the challenges related to flow uniformity and the issue of high pressure drop in the cold plate. [ABSTRACT FROM AUTHOR]

This study presents an innovative approach to enhance thermal control in the blow molding production process, specifically focusing on achieving rapid and precise temperature regulation. To address the significant time consumption during mold closure, strategically deploying thermoelectric modules (TEMs) arranged according to the mold's geometry enables meticulous temperature monitoring through integrated thermocouples. The configuration forms a matrix of interconnected TEMs, thermocouples, and controllers, orchestrating precise temperature adjustments across the mold surface. The research integrates fuzzy algorithms to facilitate seamless communication between thermoelectric devices and thermocouples for precise mold temperature control. Simulation of thermoelectric devices using COMSOL Multiphysics and implementation of fuzzy controllers in Matlab, connected through a live-link, enables real-time. I have adjustments and precise control. This integrated approach allows for a comprehensive analysis and optimization of the thermal control system, ensuring effective and adaptive temperature regulation. TEMs, operating as solid-state heat pumps, offer size versatility, adaptability to diverse mold shapes, and maintenance-free operation. Leveraging individual control capabilities significantly enhances heat transfer resolution, enabling precise manipulation of heat flux. Emphasizing the reduction of cooling time and achieving high-gloss surface quality, the study introduces the Advanced Precise Rapid Thermal Cycling in Blow Molding (APRTC) method. APRTC strategically employs TEMs to expedite cooling and elevate temperature determination accuracy, guaranteeing enhanced temperature resolution on the core mold surface. Furthermore, the study optimizes energy utilization through a closed-loop fluid circulation system, harnessing waste energy from other stages. Comparative analysis highlights APRTC's superiority, revealing a remarkable 91 % reduction in temperature differentials during the cooling cycle and an 89 % decrease in the heating stage. These findings underscore APRTC's efficacy in maintaining minimal temperature variations throughout the entire molding process. [ABSTRACT FROM AUTHOR]

The urbanization of cities, the corroding of green areas, and the increasing demand for electric energy lead to the formation of heat islands in cities and the appearance of the global climate change phenomenon. Therefore, it was necessary to resort to the use of renewable energy sources, such as geothermal energy, to be used in different applications, as it can be used to cool buildings in cities during the summer. This research deals with the benefits of using geothermal energy systems, their different types, and the possibility of their application in Egypt. Also discussing the effectiveness of the vertical closed geothermal system in residential buildings in Alexandria Governorate in Egypt to reach an answer to a question. The effectiveness of the geothermal energy system in residential buildings is to reduce the problem of rising temperatures, energy consumption for cooling, and carbon emissions and thus reduce the problem of the formation of heat islands in cities and the appearance of the global climate change phenomenon and reaching a sustainable, environmentally friendly building that achieves thermal comfort for humans through the use of a simulation program called TRNSYS-17, through which the current situation of the building was compared and the addition of a vertical closed geothermal system was assumed, the extent of its effectiveness was compared in the whole building, and the cost of a vertical closed geothermal system and a traditional air conditioning system (HVAC) in a building was compared (case study). Hence, the efficiency of the vertical closed geothermal system appeared to reduce electric energy consumption and carbon emissions in the whole building at Alexandria in Egypt, especially the ground floor, which reached thermal comfort for humans and worked to reduce electricity consumption and carbon emissions by up to 22.93% in the building as a whole. [ABSTRACT FROM AUTHOR]

Concentrating photovoltaic (CPV) technology is a promising approach for collecting solar energy and converting it into electricity through photovoltaic cells, with high conversion efficiency. Compared to conventional flat panel photovoltaic systems, CPV systems use concentrators solar energy from a larger area into a smaller one, resulting in a higher density of solar radiation and increased electrical output. However, the use of concentrators can lead to nonuniform radiation and high temperatures that may damage the solar cells. Therefore, implementing a suitable thermal management solution is crucial to ensure optimal performance of CPV systems. This review article aims to provide a comprehensive overview of recent research and technical challenges in solar concentrators, trackers, and cooling systems for mitigating temperature effects and enhancing the efficiency of CPV cells. It will explore the causes and potential solutions for temperature effects in CPV systems, particularly focusing on the components involved. [ABSTRACT FROM AUTHOR]

The manufacturing industry is rapidly moving towards sustainability, emphasizing the need for an innovative cooling system and medium that does not lead to undesirable consequences during disposal. Cooling of the tool-work interface is an essential process in machining which is traditionally accomplished using cutting fluids with various application strategies. Over the years, several techniques have been proposed and utilized to serve the purposes such as cooling the aforesaid region while washing away the chips produced through machining. However, several undesirable consequences to human and environmental wellness due to the use of cutting fluids have been reported in a number of research articles. Efforts to address this chronic issue have yielded seemingly viable solutions, such as minimum quantity lubrication (MQL) and cold air cooling (CAC), which have apparently produced surface characteristics in workpieces close to those achieved with conventional tool cooling techniques. In the light of above, the current study utilizes a thermoelectric cooling system to evaluate the after-machining effects in the absence of cutting fluids during the machining of Inconel 825 superalloy, thereby demonstrating its feasibility and potential in further research. [ABSTRACT FROM AUTHOR]