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Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The performance of critical components in a sensor testing system may be compromised in a thermal vacuum environment as a result of the impact of extreme temperatures. Moreover, the precision of the angle measurement may be influenced by the thermal deformation effect. This paper presents a simulated analysis of the temperature regulation impact of the thermoelectric cooler (TEC) and outlines the design and optimization process of a sensor test chamber that can function within a consistent temperature range. The mathematical model of TEC is utilized to suggest a design choice, taking into account the aforementioned model, in a temperature-controlled environment with thermal vacuum circumstances. Moreover, the orthogonal test method is employed in combination with the FloEFD finite element analysis to validate the effectiveness of temperature control. In addition, the parameters of the radiation radiator are tuned and designed. Therefore, the temperature range difference inside the test system decreased by 20%. The thermoelectric temperature control system's steady-state model is investigated using the PSpice simulation, based on the equivalent circuit theory. The discovered conclusions establish a theoretical foundation for improving the efficiency of temperature regulation. The design concepts presented in this work, particularly the optimization technique for radiation radiators in aerospace test equipment using thermoelectric cooling temperature control research and development, hold promise for practical implementation. [ABSTRACT FROM AUTHOR]

The energy crisis and related environmental issues due to the increasing power demand are the primary concerns in today's evolving globe. Modern energy conversion systems need dependability and scalability to overcome obstacles. This manuscript systematically examines recent research on high-performance thermoelectric materials, including novel alloys, nanostructured composites, and flexible materials designed to enhance energy conversion efficiency and adaptability across diverse environments. The literature selection spans peer-reviewed articles, patents, and emerging studies, emphasizing innovations in material properties, manufacturing methods, and design adaptations for transportation-specific challenges. In addition, this paper is organized to provide a dual perspective on both material innovation and practical integration in transportation systems, highlighting recent advancements in manufacturing processes and design. The unique structure of this review illuminates current limitations and prospective research pathways, offering insights for enhancing TEG performance and fostering sustainable, energy-efficient transportation technologies.

In the medical field, refrigeration systems are used to store and transport vaccines, blood, and other medical supplies that require specific temperature ranges to remain effective. As technology continues to advance, the demand for more efficient and sustainable refrigeration systems is also increasing. The freezer compartment is typically designed to maintain a temperature of −18°C to −23°C for storing frozen items. Consequently, this work aims to develop a hybrid refrigeration system that combines a thermoelectric cooler system (TEC) and a vapor compression refrigeration cycle (VCC) system to achieve lower temperatures than conventional refrigerators. Also, the performance of the proposed hybrid refrigeration system is experimentally assessed with various operating conditions, including varying the voltage delivered to the system. The experimental results exhibited that the temperature inside the freezer room reached −33°C, while the cold side temperature is −47°C. Also, the maximum coefficient of performance of the VCC system, TEC, and hybrid system is 2.07, 1.06, and 0.37, respectively, at a DC voltage applied of 6 V. Moreover, the results revealed that the hybrid system combining a TEC and a VCC system can be a valuable technology for specific applications with low temperatures and limited capacity requirements. [ABSTRACT FROM AUTHOR]

The simulation of energy conversion in the branches of a thermoelectric cooler is carried out. The influence of various distributions of the active impurity along the branch of the thermoelement on its efficiency in the mode of maximum temperature drop is considered. The calculation is carried out within the framework of a two-band standard model of the band structure of a semiconductor for non-degenerate charge carriers. The Thomson effect was not taken into account. [ABSTRACT FROM AUTHOR]

This work aims to describe the development of a prototype laser diode system along with its driver circuit and a stable microcontroller-based thermoelectric cooling system. The laser diode driver circuit was designed and simulated by using NI Multisim. The driver circuit was built using two LM317 ICs to control the voltage across the laser diode and current through the laser diode. The laser diode output power varies by varying the current across the laser diode through the driver circuit. The temperature of the laser diode rises with time, affecting the output power of the laser diode during a long period of operation. A microcontroller-based cooling system was designed and fabricated using thermoelectric coolers. The microcontroller controls the cooling system ON/OFF period to maintain the laser diode at a particular temperature by removing the excess heat produced during the lasing action. The laser diode with a microcontroller-based cooling system shows that the laser diode output power remains stable during a long period of operation. [ABSTRACT FROM AUTHOR]

In recent years, thermoelectric cooling has seen significant growth, driven by advancements in nanoscience and manufacturing. Concurrently, the increasing water crisis in various regions has led to a surge in research on Atmospheric Water Harvesters (AWHs) for decentralized water harvesting. This study presents a comprehensive thermodynamic and economic analysis of Thermoelectric-based Atmospheric Water Harvesters (TAWHs) with different Heat Exchanger (HX) configurations with different flow configurations. Our research identifies five types of HXs, each characterized by its own optimal geometrical and controlling parameters. These HXs are evaluated based on economy, eco-friendliness, productivity, air cooling efficiency, and compactness. We provide new insights into the hidden potential and performance of Thermoelectric Coolers (TECs) in desalination, particularly highlighting the effect of increasing the ratio of surfaces mounted with TECs to the total surface area of the channels. Our results indicate that among the HX configurations, the counter flow HX is the most economical option, capable of water harvesting at a cost of $0.230 USD per liter from an 80 % humidity level. The parallel flow HX demonstrates higher efficiency according to the second law of thermodynamics and environmental friendliness, while the crossflow HX exhibits lower overall efficiency. We found that the optimum cold channel incoming air flow rate varies with humidity in a detailed analysis of a counter flow HX with 2 columns and 15 rows. Interestingly, we found that humidity and incoming air mass flow rate have a negligible effect on power consumption. This work can be used as a guideline for future engineering problems involving the design and optimization of TAWHs.

The combined use of Extreme Gradient Boosting (XGBoost) algorithm, one of the machine learning (ML) methods, and a generalization of Hermite-Biehler theorem to obtain a novel PID controller that will ensure robustly stable and optimized operation of a micro thermoelectric cooler (Micro-TEC), which is the main part of a Polymerase chain reaction (PCR) device, is a unique approach of our study compared to previous studies. Therefore, we first established a mathematical model of the micro-TEC by making real-time measurements and then, a new data set was created to find the optimum parameter values of PID controller, and finally, XGBoost Hyperparameters with GridSearchCV was used for the first time to predict PID controller parameters. The XGBoost algorithm achieved 97% training success and 91% test success in estimating the parameters of the PID controller. Moreover, the novel controller developed using the XGBoost algorithm in this study has an impressive speed of 3 seconds. Additionally, our proposed method was compared with various metaheuristic optimization algorithms in terms of error percentage. The error percentages of XGBoost, the equilibrium optimization, the particle swarm optimization and the artificial bee colony optimization algorithms were found to be 0.4%, 1.1%, 3.7% and 11.1%, respectively. It is observed the settling times of micro-TEC with ML-PID controller for all five PCR cycles are 4.86, 44, 83.4, 123 and 162.5 seconds, respectively, and the overshoot values are below 5%. The proposed method gave the smallest settling time, error and overshoot percentages compared to these metaheuristic optimization algorithms.

Abstract In this study, a technique is suggested to enhance the temperature difference for cooling and energy efficiency of thermoelectric cooler (TEC) used in cooled detectors when subjected to high current conditions. Embedding a structure for storing heat during phase change is the basis of this method at the heat sink. A simulation model was created for a common two‐stage series TEC with an asymmetrical design, which is coupled with a structure for storing heat through phase change. The research examined how phase transition heat storage impacts the coefficient of performance (COP) and refrigeration temperature difference across various phase‐change substances, heat transfer coefficients at the hot end, currents, and the height of the phase‐change material (PCM). The findings suggest that the suggested approach of combining PCM with TEC can efficiently lower the cold end temperature of TEC by a maximum of 20 K, enhance the temperature gap by a maximum of 16 K, and preserve the consistency of the optimized quantity across various hot end heat transfer coefficients. During the phase‐change process of PCMs, the COP of TECs integrated with PCM is found to increase by an average of 2%–3% compared to TECs without PCM integration. Under the maximum current operating condition, the cryogenic temperature can be optimized to a minimum of 238 K. In summary, the proposed method of integrating phase‐change heat storage with TECs provides a promising solution for improving their cooling performance and energy efficiency in cooled detectors under high current conditions. Additional investigation can be conducted to explore the practical application of this approach and enhance the design parameters for various uses.

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Linear cooling of continuous microfluidic was achieved based on a single TEC. • Multi-structure TEC was proposed to generate a linear temperature gradient. • Numerical model was established and verified by experiment. • Linearity, cooling rate and temperature of linear cooling were analyzed. • Cooling rate can be controlled by changing the current and microfluidic velocity. Linear cooling of continuous microfluidic is crucial to the microfluidic analysis of cell cryopreservation and homogenous ice nucleation. This study presents a method to establish a linear temperature gradient for linear cooling of continuous microfluidic based on a single thermoelectric cooler. A novel multi-structure thermoelectric cooler was proposed to generate a stable linear temperature gradient. Furthermore, a numerical model was established to explore the performance of linear cooling of continuous microfluidic. Meanwhile, experiments were carried out to validate the model. Based on the proposed multi-structure thermoelectric cooler, linear cooling of continuous microfluidic can be successfully achieved, even if the current of the thermoelectric cooler or microfluidic velocity changes. For the case of current equal to 3 A and microfluidic velocity equal to 50 mm/s, microfluidic can be linearly cooled from 297 K to 251 K with a cooling rate of 64.5 K/s and linearity of 0.9912. It was also found that the temperature gradient decreases slightly with increasing microfluidic velocity while the cooling rate increases and is approximately proportional to the microfluidic velocity. With the increase of microfluidic velocity , the linearity increases at first and then decreases. Maximum goodness of fit equal to 0.9942 appears at the microfluidic velocity of 20 mm/s. [ABSTRACT FROM AUTHOR]

An oxygen-free copper-based cell has been designed to perform X-ray scattering experiments from the solid-supported lipid membranes immersed in water. This cell can be used to investigate the structural changes in the membrane depending on the composition of the lipids, the effects of temperatures, and the changes in arrangements of the lipids in the membrane on the addition of the external molecules. The design of the cell has been optimized to get a good signal-to-noise ratio (SNR) for the measurements of X-ray reflectivity and grazing incidence diffraction by controlling the X-ray path within the liquid in the cell and easy operation for variable liquid temperature. This very low-cost temperature-controlled setup, developed in our laboratory, can perform in situ X-ray measurements at various temperature ranges—starting from around 4°C up to 70°C which is very relevant to study the phase transition temperature of the lipids constituting the cell membranes. The detailed mechanical design of the cell and electrical control mechanism of the temperature of the liquid inside the cell has been discussed here. One such X-ray reflectivity measurement is shown here to express the capability of the cell for the study of the solid-supported bilayer sample composed of dipalmitoyl phosphocholine lipid at two different temperatures, below its phase transition temperature. [ABSTRACT FROM AUTHOR]

Most laser diodes experience fluctuations in intensity, phase, and wavelength, predominantly due to heating from energy conversion to thermal energy and changing ambient temperatures. This study primarily focuses on countering the effects of temperature variations through the design and implementation of a laser diode temperature controller (LDTC) for the fiber optical interferometer system. Additionally, there are other contributing factors, including the injected current, noises, and acoustic disturbances, that play significant roles in these fluctuations. Despite these additional factors, our findings emphasize that temperature remains the principal contributor to these fluctuations. The LDTC developed in this work is cost-effective and rapidly responsive to temperature changes, ensuring precise control over the laser diode's temperature. The findings show the ability of this controller to maintain the temperature of a laser diode at a constant value with a precision (steady-state error) of 0.0013°C (0.0396°C without the laser diode) and an average fluctuation of 0.0567°C (0.0742°C without the laser diode). Furthermore, the study establishes a relationship between the length of the measurement object and temperature. This laser diode controller was investigated to measure the wavelength-dependent temperature changes at the interferometric point sensor. [ABSTRACT FROM AUTHOR]

Thermoelectric coolers (TECs) have a high potential to dominate traditional air conditioning and become the future of HVAC (heating, ventilation, and air conditioning). TECs offer several advantages over traditional air conditioning systems, most notably in terms of zero greenhouse gas emissions, a leak-free environment, and cost efficiency. Despite all these concerns, efficient cooling performance and energy consumption are two major barriers for the rapid adoption of TECs. This article provides a comprehensive literature review of recent developments and challenges in implementing TECs to increase energy consumption and cooling performance. In particular, through the development of components and physical parameters such as thermoelectric material, the effect of fluid flow and the geometry of the heat sink of the thermoelectric cooling system. In addition, the articles will highlight the significant opportunities for thermoelectric applications to achieve economic and environmental benefits. Thermoelectric cooling with the latest conversion efficiency is technically practical and economical for small and micro applications in the current scenario. If thermoelectric cooling is applied on a large and medium scale in commercial practice, it would further develop green technology that improves environmental conditions as well as the energy supply. [ABSTRACT FROM AUTHOR]

In this study, a technique is suggested to enhance the temperature difference for cooling and energy efficiency of thermoelectric cooler (TEC) used in cooled detectors when subjected to high current conditions. Embedding a structure for storing heat during phase change is the basis of this method at the heat sink. A simulation model was created for a common two‐stage series TEC with an asymmetrical design, which is coupled with a structure for storing heat through phase change. The research examined how phase transition heat storage impacts the coefficient of performance (COP) and refrigeration temperature difference across various phase‐change substances, heat transfer coefficients at the hot end, currents, and the height of the phase‐change material (PCM). The findings suggest that the suggested approach of combining PCM with TEC can efficiently lower the cold end temperature of TEC by a maximum of 20 K, enhance the temperature gap by a maximum of 16 K, and preserve the consistency of the optimized quantity across various hot end heat transfer coefficients. During the phase‐change process of PCMs, the COP of TECs integrated with PCM is found to increase by an average of 2%–3% compared to TECs without PCM integration. Under the maximum current operating condition, the cryogenic temperature can be optimized to a minimum of 238 K. In summary, the proposed method of integrating phase‐change heat storage with TECs provides a promising solution for improving their cooling performance and energy efficiency in cooled detectors under high current conditions. Additional investigation can be conducted to explore the practical application of this approach and enhance the design parameters for various uses. [ABSTRACT FROM AUTHOR]

This document discusses a study that investigated the integration of thermoelectric coolers (TECs) into a solar air heater (SAH) to improve its performance. The study conducted outdoor tests and found that the integration of TECs improved the heat collection and energy efficiency of the SAH. By using the output energy from a photovoltaic (PV) module to power the TECs, the SAH achieved a higher outlet air temperature and reduced heat loss. The study concludes that incorporating TECs into solar air heaters is a viable means of improving their thermal performance. The document also includes a list of symbols used and acknowledges the funding sources for the research. [Extracted from the article]

With the development of 5G technology and increasing chip integration, traditional active cooling methods struggle to meet the growing thermal demands of chips. Thermoelectric coolers (TECs) have garnered great attention due to their rapid response, significant cooling differentials, strong compatibility, high stability and controllable device dimensions. In this review, starting from the fundamental principles of thermoelectric cooling and device design, high-performance thermoelectric cooling materials are summarized, and the progress of advanced on-chip TECs is comprehensively reviewed. Finally, the paper outlines the challenges and opportunities in TEC design, performance and applications, laying great emphasis on the critical role of thermoelectric cooling in addressing the evolving thermal management requirements in the era of emerging chip technologies.

The thermoelectric cooler (TEC) operating under the transient mode showed a stronger short term cooling effect than that of the steady state mode. In this study, a chip cooling experimental setup with the chip modeled by a ceramic heater was constructed using a commercial Bi2Te3-based TEC. A transient three-dimensional numerical model was established for the system optimization. The impacts of the pulse voltage amplitude, pulse voltage trigger time, pulse voltage time span, and the power magnitude of the chip on the peak temperature of the chip were analyzed in detail. The results showed that the experimental and numerical simulations were in high agreement with an error of only 3.6 %. When a pulse voltage of 12 V was applied to the TEC, the experimental results showed that the peak temperature of the chip with a pulse power of 48 W was reduced by 15.3 °C, while the simulation results demonstrated a reduction of 15.6 °C. The increase in the pulse voltage width and the pulse thermal power resulted in a larger temperature reduction. The transient cooling effect of the TEC presented a promising solution for temperature regulation in modern chips operating under dynamic power conditions.

The current need, from the point of view of increasing the sustainability of electric vehicles (more and more present in the car market), makes the research in the field to be focused on the analysis of the factors that can lead to an increase electric vehicle batteries' lifespan. Since this is directly related to the temperatures reached during operation and the thermal gradients inside the battery packs, this paper presents the analysis of the cells' lifespan through artificial intelligence methods and techniques, evaluating the influence of the constructive and functional characteristics of two air-based hybrid thermal management systems (CHA - composite material + heat pipe + forced air convection and CTA - composite material + thermoelectric cooler + forced air convection). The construction of the thermal management system is a special and innovative one, being a composite material (epoxy flame-retardant resin and 2 wt% hexagonal boron nitride nanoparticles) chosen as the primary thermal energy dissipation element. The research was carried out experimentally on individual cells and on a battery module (consisting of 12 cylindrical Li-ion 18650 cells), the battery module being discharged at a rate of 3C with the temperatures recorded from 15 locations inside the battery module, which allows assessing the local and global influence of the thermal management systems. Predictions on the lifetime of the cells in the battery module were made using a convolutional neural network and showed that by using the proposed fireproof thermal management systems, the cells’ lifespan increases by 26.9 … 154.4% (depending on the implemented thermal management system and the location of the cell in the battery module).

Abstract As for improving the heat diversion capacity of the hot side heat sink of the thermoelectric cooler (TEC), thereby improving the operational performance of the TEC, this study designed a type of double‐embedded flat heat pipe (EFHP) finned heat sink and compared with a standard aluminum (Al) heat sink. In experimental studies, TEC under two heat sinks were placed under different operating currents for heat transfer analysis and performance comparison. The experimental results demonstrated that the EFHP heat sink had better heat diversion ability, effectively improving the operational performance of TEC. When the TEC was input with a current of 6A, the thermal resistance of the double EFHP finned heat sink decreased by 19% compared to the Al heat sink; cooling capacity and coefficient of performance increased by 8.3% and 9.46%, respectively. Further, TEC's cold and hot surface temperatures decreased by 10.83% and 10.2%, respectively, and the heat uniformity of the heat sink improved. In addition, the CFD software Icepak was used to analyze the effects of double flat heat pipe spacing and length on the heat sink and TEC and the performance of two heat sinks and TEC under different heat dissipation conditions and obtained good agreement. This study can provide further guidance and assistance in designing the TEC cooling system.

The performance of critical components in a sensor testing system may be compromised in a thermal vacuum environment as a result of the impact of extreme temperatures. Moreover, the precision of the angle measurement may be influenced by the thermal deformation effect. This paper presents a simulated analysis of the temperature regulation impact of the thermoelectric cooler (TEC) and outlines the design and optimization process of a sensor test chamber that can function within a consistent temperature range. The mathematical model of TEC is utilized to suggest a design choice, taking into account the aforementioned model, in a temperature-controlled environment with thermal vacuum circumstances. Moreover, the orthogonal test method is employed in combination with the FloEFD finite element analysis to validate the effectiveness of temperature control. In addition, the parameters of the radiation radiator are tuned and designed. Therefore, the temperature range difference inside the test system decreased by 20%. The thermoelectric temperature control system’s steady-state model is investigated using the PSpice simulation, based on the equivalent circuit theory. The discovered conclusions establish a theoretical foundation for improving the efficiency of temperature regulation. The design concepts presented in this work, particularly the optimization technique for radiation radiators in aerospace test equipment using thermoelectric cooling temperature control research and development, hold promise for practical implementation.

Solar air heating systems are continuously being improved by combining them with other energy conversion technologies. In this paper, outdoor tests were carried out on a thermoelectric heat-pumping solar air heater (TE-SAH), with four (04) TECs (TEC1–12706) attached to the backside of the absorber plate, and powered by a 40Wp mono-Si PV module to pump heat from the absorber plate into the heated air. The thermal energy production, energy efficiency, heat loss coefficients, and heat removal factor were evaluated and compared with a reference system without TECs. The heat collection and energy efficiency of the solar air heater were improved by 7.14 % and 66.71 %, respectively, with the integration of TECs. Heat losses also decreased by 0.46 MJ. Furthermore, the estimated heat removal factor for the TE-SAH was 0.55, higher than 0.49 obtained for the reference SAH. These results showed that PV-TE heat-pumping is a viable means of improving the thermal performance of solar air heaters.

The extraction of water from the atmosphere is considered as a potential solution to alleviate the problem of water shortages. Therefore, it is crucial to improving the efficiency of water production from atmosphere. In this work, the effect of temperature of the condensing surface below 0 °C on the water productivity of thermoelectric water generator (TWG) has been studied for the first time. The experimental results indicate that the average water productivity increases with the decrease of the condensing fin surface temperature and there is a maximum increase of 186 % in the average water productivity of TWG when the temperature of condensing fin surface decreases from 5 °C to −10 °C, which is due to the increased temperature difference and the enhanced thermal conductivity of the ice layer. When the form of condensation on the surface of condensing fins is changed from condensing to frosting, the water productivity is increased by 22.1 % at maximum, which can be attributed to the higher thermal conductivity of ice than water. The effect of the sampling time on average water productivity of TWG has also been studied. With the increase of sampling time (0.5 h–3.5 h), the average water productivity of the device gradually decreases by 30.3 %. And the highest average productivity of TWG has been observed at a sampling time of 0.5 h. In addition, the effects of flow rate of water in water block heat exchanger, air flow rate of the cooling fan, voltage of TEC on water productivity are experimentally investigated as well. This study provides a strong theoretical foundation for enhancing the water productivity from humid air.

As for improving the heat diversion capacity of the hot side heat sink of the thermoelectric cooler (TEC), thereby improving the operational performance of the TEC, this study designed a type of double‐embedded flat heat pipe (EFHP) finned heat sink and compared with a standard aluminum (Al) heat sink. In experimental studies, TEC under two heat sinks were placed under different operating currents for heat transfer analysis and performance comparison. The experimental results demonstrated that the EFHP heat sink had better heat diversion ability, effectively improving the operational performance of TEC. When the TEC was input with a current of 6A, the thermal resistance of the double EFHP finned heat sink decreased by 19% compared to the Al heat sink; cooling capacity and coefficient of performance increased by 8.3% and 9.46%, respectively. Further, TEC's cold and hot surface temperatures decreased by 10.83% and 10.2%, respectively, and the heat uniformity of the heat sink improved. In addition, the CFD software Icepak was used to analyze the effects of double flat heat pipe spacing and length on the heat sink and TEC and the performance of two heat sinks and TEC under different heat dissipation conditions and obtained good agreement. This study can provide further guidance and assistance in designing the TEC cooling system. [ABSTRACT FROM AUTHOR]

This research study is the preliminary phase of an effort to develop a generic data transfer method via human haptic thermal sensation (i.e., a coded language such as Morse or Braille). For the method to be effective, it must include a large variety of short, recognizable cues. Hence, we propose the concept of cues based on sequences of thermal pulses: combinations of warm and cool pulses with several levels of intensity. The objective of this study was to determine the feasibility of basing a generic data transfer method on haptic thermal cues using sequences of short pulses. The research included defining the basic characteristics of the stimuli parameters and developing practical methods for generating and measuring them. Several patterns of different sequences were designed considering the relevant data known to date and improved by implementing new insights acquired throughout the tests that were conducted. The final thermal cues presented to the participants were sensed by touch and clearly recognized. The results of this study indicate that developing this new method is feasible and that it could be applicable in various scenarios. In addition, the low impact measured on the user's skin temperature represents an inherent advantage for future implementation. This report presents promising findings and offers insights for further investigations. [ABSTRACT FROM AUTHOR]

The effect of the arrangement of thermoelectric cooler （TEC） on the natural convection characteristics of air in the cooling chamber of airborne avionics is studied by experimental research and numerical simulation. The results show that when the air is cooled, its temperature decreases while its density increases, and it begins to sink at a slow speed. Its motion form gradually transitions from deformation to rotation. It is more beneficial to the development of flow field to arrange all the TECs at the top of the chamber. However, when the air sinks to the bottom of the cooling chamber, it is easy to produce oscillation solutions, fork flow and secondary flow, and the flow enters the chaotic state. Through comparative analysis of six design cases, the best arrangement of TEC in the cooling chamber of the airborne avionics with the minimum temperature inhomogeneity coefficient and the lowest average air temperature is given. [ABSTRACT FROM AUTHOR]

Abstract This study produced a numerically optimum design of a mini refrigerator with a thermoelectric cooler (TEC) powered by a thermoelectric generator (TEG) system in a turbocharged tractor. The effect of the cross-sectional areas of the thermocouples constituting the TEC on the energy transformation from electricity to thermal was examined. Analyses were performed for five different modules; the p- and n-type thermocouple numbers of each of these were also the same. Thus, the effect of the distance between thermocouples on the performance of the TEC module could be determined. This is the significance of the current study for the literature. The results of the analysis using the Ansys-Thermal-Electric software were for one TEC module of each different size. According to the results of the numerical analysis, the increase in electric current in the TB-127-1.2-1.3 module was 42% compared to the TB-127-1.0-1.3 commercial module. Moreover, the cooling power of the TB-127-1.2-1.3 module was 42.72% higher than the cooling power of the TB-127-1.0-1.3 commercial module. The electrical power requirement of the TEC modules, except for the TB-127-1.1-1.3 and TB-127-1.2-1.3 TEC modules, could be met with all the TEG modules at an outdoor temperature of 30 °C. [ABSTRACT FROM AUTHOR]

In this study, a hybrid BTMS (battery thermal management system) that combines TEC (thermoelectric cooler) and PCM (phase change material) is shown. The PCM absorbs heat and occurs in phase change, which stores the heat from batteries. The TECs act as a heat pump, takes away the excess heat in the PCM through the fins, and control the temperature of the PCM below the phase transition temperature as much as possible, which can prevent it from melting completely and losing the ability to keep the battery temperature stable. By comparative analysis, the addition of PCM can obtain better temperature uniformity, the temperature difference was controlled below 6 °C, and CPCM with higher thermal conductivity was more suitable for the hybrid BTMS, at 1200 s, the maximum temperature of the model with 30% EG/RT44HC was 10.3 °C lower than that with pure RT44HC. When the fill thickness of CPCM increases, the temperature control time can be extended, but the performance of TEC will decrease. For this model, the arrangement direction of the fins should be perpendicular to the direction of the battery which has higher thermal conductivity, heat from batteries can be effectively transferred to the fins more and faster.

In recent studies, Thermo-Electric Coolers (TEC) have been utilized for dehumidification purposes, which is mainly based on the extraction of moisture from humid atmospheric air. The reviewed literature showed that the rate of water collection from the TEC-based system can be affected by various parameters such as the module’s input voltage, the heat sink orientation, and tilt angles. In this research, the analysis of variance (ANOVA) was used to examine the significance of these factors and their interaction within the system on the TEC-based dehumidification system. Four levels were investigated for both, the Peltier’s input voltage and the rotation angle, and three levels for the tilt angle. This study indicated the significance of the studied factors and their interactions within the dehumidification system along with performing an overall numerical optimization. The experiments were conducted under the same working conditions in an enclosed environment to minimize errors. According to the overall numerical optimization, which was validated experimentally, the optimum system performance was predicted to be obtained at approximately 6.8V Peltier input volt, 65° rotation angle, and 90° tilt angles, with predicted optimum productivities of 0.32278 L/kWh and 13.03 mL/hr. For the same set of parameters, the variation between the experiment and the numerical optimization was less than 4%. The experiments show that when optimizing water collection rates for thermoelectric cooling heat sinks​ under high humidity conditions, the orientation of the heat sink should be considered.

Thermoelectric (TE) technology is promising for reducing thermal discomfort of workers during their routine professional activities. In this manuscript, a preliminary evaluation of a newly developed personal cooling system (PCS) with flexible TE modules is presented based on an analysis of cooling efficiency and power consumption. For this purpose, tests with human participation were performed involving the monitoring of local skin temperature changes and electrical parameters of the controller. Thanks to TE cooling, a significant reduction of local skin temperature was observed at the beginning of the experiment, reaching as much as 6 °C. However, the observed effect systematically became weaker with time, with the temperature difference decreasing to about 3 °C. Cooling efficiency stayed at the same level over the ambient temperature range from 25 °C to 35 °C. The obtained results showed that a proper fitting of the PCS to the human body is a crucial factor influencing the PCS cooling efficiency. [ABSTRACT FROM AUTHOR]

Air conditioning has become a necessity in people's daily life. The performance of the compressor determines the energy efficiency ratio of this electrical equipment, but the heat generated during the operation of its internal core power components will greatly limit its performance release, so it is urgent to carry out research on the heat dissipation of power devices. In this work, we explore the application of thermoelectric coolers (TECs) in the field of power device heat dissipation through finite element simulation. First, we geometrically modeled the structure and typical operating conditions of core power devices in air conditioners. We compared the temperature fields in air-cooling and TEC active cooling modes for high-power-consumption power devices in a 319 K operating environment. The simulation results show that in the single air-cooling mode, the maximum temperature of the 173.8 W power device reached 394.4 K, and the average temperature reached 373.9 K, which exceeds its rated operating temperature of 368.1 K. However, the maximum and average temperature of the power device dropped to 331.8 K and 326.5 K, respectively, at an operating current of 7.5 A after adding TECs, which indicates that TEC active cooling has a significant effect on the temperature control of the power device. Furthermore, we studied the effect of the TEC working current on the temperature control effect of power devices to better understand the reliability of the TECs. The results show that TECs have a minimum working current of 5 A, which means it has no significant cooling effect when the working current is less than 5 A, and when increasing the current to 10 A, the average temperature of the power device can be reduced to 292.9 K. This study provides a meaningful exploration of the application of TECs in chip temperature control and heat dissipation, providing a new solution for chip thermal management and accurate temperature control. [ABSTRACT FROM AUTHOR]

Similar to biological muscles in nature, artificial muscles have unique advantages for driving bionic robots. However, there is still a large gap between the performance of existing artificial muscles and biological muscles. Twisted polymer actuators (TPAs) convert rotary motion from torsional to linear motion. TPAs are known for their high energy efficiency and large linear strain and stress outputs. A simple, lightweight, low-cost, self-sensing robot powered using a TPA and cooled using a thermoelectric cooler (TEC) was proposed in this study. Because TPA burns easily at high temperatures, traditional soft robots driven by TPAs have low movement frequencies. In this study, a temperature sensor and TEC were combined to develop a closed-loop temperature control system to ensure that the internal temperature of the robot was 5 °C to cool the TPAs quickly. The robot could move at a frequency of 1 Hz. Moreover, a self-sensing soft robot was proposed based on the TPA contraction length and resistance. When the motion frequency was 0.01 Hz, the TPA had good self-sensing ability and the root-mean-square error of the angle of the soft robot was less than 3.89% of the measurement amplitude. This study not only proposed a new cooling method for improving the motion frequency of soft robots but also verified the autokinetic performance of the TPAs. [ABSTRACT FROM AUTHOR]

A compressor is the most power-consuming component in a refrigeration system, and energy scarcity in the form of electricity has become a grave challenge in today's world. Replacing the compressor with solar-powered clean energy could be an efficient alternative to reduce energy consumption significantly. The system presented comprises a Solar-powered Thermal Refrigeration System based on the Peltier Effect, functioning on a cooling module. Since the system is solar-powered, an automatic solar tracker that incorporates Light Dependent Resistors and a servo motor is integrated to supply maximum power by continuously orienting the panel in the direction of sunlight and thus always keeping it charged. This research aims to analyse the performance of a solar-powered thermoelectric refrigeration system. The model developed is a promising alternative for domestic refrigerators, accounting for a 44–63% drop in power consumption to cool a commensurate capacity refrigerator of 2.6L. From definitive experimentation, the lowest temperature of 15.15°C was achieved within the refrigeration chamber after powering the circuit for 136 seconds. Initially, the air inside the refrigeration chamber at 22.48°C (ambient temperature) was dropped by 7.33°C. A high COP of 0.54 is achieved on experimentation. [ABSTRACT FROM AUTHOR]

Mass-produced thermoelectric modules are mainly fabricated with Bi2Te3-based materials. Due to the limited world reserves and the high price of tellurium, it must be saved. The miniaturization of thermoelectric converters is one of the modern trends to diminish the use of tellurium, reduce the cost of modules and expand the range of their applications. The main disadvantage of miniature thermoelectric converters operating in cooling or generating modes is their low energy efficiency, caused by the effect of electrical and thermal resistances of contacts, interconnectors and insulating plates. We propose an improved method for evaluating the maximum efficiency that takes into consideration the impact of these unwanted resistances. This method can also be used to design the modules with the optimal structure for cooling and energy generation, and not only to study their performance. The effect of undesirable electrical and thermal resistances on the maximum efficiency of cooling and generating converters made of Bi2Te3-based materials is analyzed. It is shown that the efficiency of miniature modules can be significantly improved if these resistances are reduced to their rational values. The decrease in electrical contact resistance is the predominant factor. The rational values to which it is advisable to decrease the electrical contact resistance have been determined. In the development of miniscale module technology, it is necessary to focus on such rational contact resistance values. [ABSTRACT FROM AUTHOR]

Electric motors and generators underpin life in today's world. They are numerous and widespread and consume approximately 45% of the world's energy. Any improvements in efficiency or reductions in their whole-of-life costs are actively and continually being sought. While designs accommodate the removal of heat caused by internal losses because of inefficiencies, temperature variations due to load changes and environmental temperature fluctuations, and system harmonic content still stresses electrical insulation systems. This causes the fretting of insulation, combined with moisture ingress, which leads to leakage currents and, consequently, the early failure of the electrical insulation. This paper explores the addition of thermoelectric coolers/heaters (TECs) or Peltier effect devices. We show that these solid-state devices can actively support the thermal management of a motor by keeping its internals hot, reducing moisture ingress when off, and assisting in heat removal when under load, resulting in a more thermally stable internal environment. A thermally stable environment inside the electrical machine reduces the mechanical stresses on the electrical insulation, resulting in a longer operational life and reducing the whole-of-life costs. [ABSTRACT FROM AUTHOR]

The direct additive manufacturing, such as Direct Ink Writing (DIW), of silicone parts holds cost and complexity advantages. However, for extruding strands of low viscosity heat curing silicone rubbers, a build plate temperature of up to 90°C is used, which comes with the challenge of early vulcanization inside the printhead. Thus, this paper presents a thermoelectric cooler for universal printheads. At a build plate temperature of 90°C it prolongates vulcanization by 198.5 % (∆t pot life = 508.8 s), which allows a reduction of print speed for higher quality. Additionally, the influence of external temperature is reduced and the viscosity can be controlled. [ABSTRACT FROM AUTHOR]

The thermoelectric cooler (TEC) and thermoelectric generator (TEG) modules have several appealing features, including fixed parts, high reliability, low maintenance costs, and seamless connection with other heating equipment, accompaniment, can be powered by a variety of low-energy renewable energy sources such as solar water/air collectors, ground heat exchangers or heat from biomass. The thermoelectric assembly was integrated into the TEC using the TEG in this study. A prototype was developed in which recently developed thermoelectric modules were integrated into a thermoelectric cooler. For this purpose, a TEC sandwiched between two TEGs with different heat transfer conditions was established, to simulate the heat transfer and thermoelectric behavior of both the TEG and the TEC system, and evaluate the effect of the combined TEG-TEC on the performance parameters of the good system by comparing different cooling modes ranging from natural convection, forced convection, and water-cooling tests. It was shown that to the natural convection of heat transfer, as the TEC voltage increases, the hot surface temperature of the upper TEG increases, and the cold surface temperature of the lower TEG decreases, where the lowest TEC temperature reaches 1.36 A. When using forced convection (by using a fan), the temperature profile decreases over time, starting at around 70 ° for 7V, and after almost 60 minutes, the temperature drops to around 45 ° for 3V. This turned out to be a match between experiment and theory in all traces shown, with a voltage difference of 25 mV for 3V TEC and ending at 70 mV for 8V TEC. [ABSTRACT FROM AUTHOR]

Thermoelectric coolers (TEC) are devices that conversion of electrical power into a temperature gradient. TEC modules have the benefits of high dependability, small dimensions, lightweight, absence of mechanical moving parts and working fluid. Thermoelectric cooling systems have experienced significant utilisation in recent years. These technologies have been used in automobiles to cool and maintain the quality of goods during transportation and in portable cooling bags, computers, and medical apparatus. The TEC manufacture datasheet only offers limited data on characteristics and maximum parameters, which is insufficient for studying thermoelectric systems. This paper presents an analytical modelling methodology that provides a direct method for assessing the performance of module parameters and determining the fundamental thermal physical parameters of a TEC. Furthermore, this article outlines the procedure for choosing the appropriate TEC module from a selection of three options to integrate it with a vapour compression refrigeration (VCR) system. The objective is to attain low temperatures while reducing power consumption and improving performance. The findings indicates that The TEC1-12706 module was the most suitable option among three different types of TEC modules for integration with the VCR system to achieve low temperatures. This choice was based on its lower power consumption than the TEC127010 and TEC127015 modules, resulting in 36.5% and 59.3% energy savings, respectively. Additionally, the heat dissipation from the hot side of the TEC12706 is lower than the TEC12710 and TEC12715 modules by 32.2% and 59%, respectively.

The lithium-ion battery is now abundantly available in the market due to its excellent performance. However, battery overheating is increasingly prominent when the battery discharges at high speed. In this study, an active-passive BTMS (Battery Thermal Management System) combining PCM (Phase Change Material) and TEC (Thermoelectric Cooler) was proposed. The effects of different TEC currents and delayed cooling at different PCM melting rates were analyzed under the 4C discharge condition to enhance the thermal performance. The results demonstrate that battery temperature gets effectively controlled as the TEC current increases, but the temperature difference and PCM utilization are poor. However, applying a delayed current after the PCM melting rate reaches 80% reduces energy consumption and provides better temperature uniformity. Considering the large battery heat under 4C discharge, combined with the transient supercooling effect of TEC, a continuous pulse current was used to provide additional cooling power. Results show that the battery with TEC pulsed current operates 57.8% longer at 40 °C with a temperature difference maintained at 2.5 K under 4C discharge conditions compared with the PCM model.

The advent of innovative engineering concepts and technologies to improve traditional systems for refrigeration, storage, and transportation of foods is inevitable to reduce energy consumption and thus reduce greenhouse gas emissions from the food sector. In this study, a Phase Change Material (PCM) based Thermoelectric (TE) refrigerator has been presented. As a novelty, the proposed prototype is evaluated experimentally with different tests by using the wind tunnel and temperature controller. The results indicate that the PCM-based TE refrigerator can maintain the temperature of a variety of food products for applications such as refrigerator vehicles. The suggested system can keep materials at temperatures below 5 ºC for 7 h without electricity. Based on the findings, by using PCM, the proposed refrigerator can maintain the temperature of the food items below 5 ºC without electricity for 29.4% of one week's hours facilitating the system for applications with unstable access to electricity. Furthermore, the life cycle environmental impacts (including global warming potential and ozone depletion) of the PCM-based TE refrigerator have been determined and compared with conventional refrigerators. The global warming potential, ozone depletion, smog, acidification, and eutrophication of the proposed refrigerator are found to be, 1190 kg of CO2 e, 1.29E-06 kg of CFC-11, 58.5 kg of O3, 15.8 kg of SO2, and 0.242 kg of nitrogen, respectively, which is about 28% lower than the magnetic refrigerator's CFC-11 emissions. Consequently, the results conclusively demonstrate that transitioning to a PCM-based TE refrigeration system significantly reduces the environmental impacts of the food transportation and storage sector.