Thermoelectric Cooling System Research Articles

Performance and regression analysis of air-cooled thermoelectric cooling system using response surface methodology and numerical simulation

In this study, the response surface methodology (RSM) combined with numerical simulation (NS) techniques is used to perform regression model of an air-cooled thermoelectric cooler (TEC) system. To obtain the interaction models between the thermal resistance (Rh) of the external hot-side heat sink and the internal structure parameters of the TEC (leg height, h; leg width, w; numbers of P/N leg pairs, N), regarding the key performance of the TEC. According to the NS and RMS results Imax, Qcmax, and Qh decline with the rise of Rh under different N, h, and w. The decline rate is rise with the elevation of N, the increase of the w, and the decrease of the h. COP and Tcmin decrease with an increase in h, while increase with an increase in w, N, and Rh. The key factors Rh, w, h and N in the air-cooled TEC system are studied using RSM. The second-order response models for the response variables (COP, Tcmin, Qcmax,Imax and dTmax) with respect to the influencing factors (Rh, w, h and N) are established using the Box-Behnkn Design (BBD) method in RSM.

Thermal Performance Investigation of Thermoelectric Cooling System with Various Hot-Side Cooling Methods

Thermal Performance Investigation of Thermoelectric Cooling System with Various Hot-Side Cooling Methods

A Smart Jacket with Portable Thermoelectric Cooling System

This paper introduces a cutting-edge, self-contained cooling jacket design and its practical implementation. The jacket utilizes Peltier modules and a water circulation system to efficiently transfer heat, completely eliminating the need for traditional compressors or refrigerants. The key components of this innovative system include aluminum blocks housing Peltier modules, dual-loop water coolant systems, a compact suction fan, a radiator, two submersible pumps, and a rechargeable Lipo battery. The cooling process involves water circulating through the aluminum blocks to effectively dissipate heat generated by the Peltier modules. The heated water then traverses a path through plastic pipes, the radiator, and a holding tank, and ultimately returns to the aluminum blocks, while the cold water travels from the tank to the aluminum blocks via copper tubing. This ingenious configuration delivers remarkable cooling performance without relying on conventional cooling components. Extensive laboratory testing of the system confirmed its capability to achieve cooling temperatures up to 10°C below the ambient temperature. These results signify the promising potential of the cooling jacket across various applications, especially those requiring a portable and self-contained cooling solution. Such applications include critical scenarios like military and first responder operations, demanding industrial and construction settings, and scenarios involving individuals with medical conditions exacerbated by heat. The innovative cooling jacket offers a highly efficient and versatile solution for a wide range of practical needs.

EXPERIMENTAL AND NUMERICAL STUDY ON EFFECTS OF NEW-GENERATION FINNED HEAT EXCHANGER ON THERMAL PERFORMANCE OF THERMOELECTRIC COOLING SYSTEMS

In this study, an attempt has been made to increase the efficiency of the thermoelectric refrigerator by designinig a new-generation finned heat exchanger. Surface extension, which is one of the most applied passive heat transfer enhancement techniques, was applied for this finned heat exchanger. In this application, the heat absorbed from the cooling room is transferred to the external environment more effectively. In addition, by using an external thermoelectric element (which is installed with the secondary heat exchanger), the heat exchanger cools down faster and the heat is transferred to the environment more quickly. The manufactured cooling system was tested experimentally under different working conditions, including natural and forced convection. The effects of air velocity and applied voltage to the external TE module on thermal performance were examined. Additionally, the external finned heat exchanger has been simulated and heat transfer characteristics have been evaluated using computational fluid dynamics. The lowest and highest COP values have been obtained as 0.003 and 0.011, respectively, when the external TE module has been passive. By providing 12 V for the external TE module, the lowest and highest COP values have been observed as 0.0031 and 0.0042, respectively. In addition, the importance of surface extension applications for the efficient operation of thermoelectric elements has been emphasized.

Experimental analysis of the temperature distribution inside vaccine freezer compartment based on hybrid refrigeration system

Recently, the demand for refrigeration globally has been increasing in the fields of vaccine storage, medical services, food preservation, and cooling for electronic components. This has resulted in the generation of more electrical power and thus releasing more CO2 around the world which has led to many climatic changes, such as global warming. The vapour compression refrigeration cycle (VCC) is the most common as it has a high coefficient of performance (COP), although it only operates down to temperatures of around −20 °C. The thermoelectric cooler (TEC) modules offer a featured method for cooling technology, which is not mainly considered by energy efficiency but offers distinctive merits in specific applications. Although the TEC system is not conventionally known for incomparable energy efficiency, it offers a range of exceptional attributes that make it a desirable option for certain scenarios. Therefore, this work aims to assess the performance of the innovative hybrid vaccine freezer system depending on how well the VCC system and the TEC work together. Also, the temperature distribution within the freezer compartment has been investigated under various operating conditions. The newly developed hybrid vaccine refrigerator system consists of four pieces of TEC-12706 modules that function well at low temperatures. The results indicate that the best coefficient of performance (COP) of 1.05 is achieved with a total power consumption of 172.8 W when the TEC is operating at 5.5 V and the fan is running at 12 V. The cooling capacities of the freezer and cooler compartments are 9.2 W and 165 W, respectively. Furthermore, the best distribution and lowest temperatures were obtained, with temperatures in the lateral area of −40 °C compared with −37 °C in the central area.

Thermal Analysis to Achieve Low Temperature with Thermoelectric Cooling System

Thermal Analysis to Achieve Low Temperature with Thermoelectric Cooling System

Parabolic Mirror‐Assisted Thermoelectric and Radiative Cooling System for Maximizing Power Generation Utilizing Solar and Outer Space Thermodynamic Resources

AbstractRadiative cooling technology is extensively researched as a green technology, leveraging outer space as a thermodynamic resource. Recently, integrating thermoelectric generators (TEGs) and radiative coolers (RCs) are proposed to generate power using the temperature difference between the ambient and the radiative cooler. However, current TEG‐RC systems only utilize one thermodynamic resource, resulting in suboptimal efficiency. It proposes a parabolic mirror‐assisted TEG‐RC system that fully utilizes both the Sun and outer space as thermodynamic resources. The system places the hot side of the TEG, covered by a solar absorber (SA), at the focal point of the parabolic mirror, while the RC is located on the cold side of the TEG. Theoretical and experimental results reveal the optimal ratio between the RC and SA sizes to balance the power mismatch between cooling and heating powers. It also finds that the number of TEG stacks significantly affects power generation efficiency and determines the optimal number. Outdoor measurements demonstrate exceptional power generation during the daytime, which is an unprecedented achievement. This study also demonstrates the further enhancement in power generation efficiency when the proposed system is integrated with concentrated solar cells instead of the SA.

Novel design of thermo-electric air conditioning system integrated with PV panel for electric vehicles: Performance evaluation

Traditional air conditioning may be inappropriate for electric vehicles due to its moving parts noise besides using chlorofluorocarbons that harm the environment. In addition, it consumes a significant portion of the stored energy in batteries, reducing the vehicle's driving range. So, in this paper, a novel design of thermo-electric cooling (TEC) system coupled with a photovoltaic (PV) panel replacing the vehicle roof is studied. This system consists of a sandwich of PV panel outside the vehicle and TEC inside with a heat sink system integrated between them. The air temperature variation in the cabin during the daytime is predicted by solving a complete mathematical transient thermal model of the whole system before and after mounting the cooling system. The air streams through the vehicle moving are exploited to improve the TEC and PV system performance. The system performance is investigated for different cases during the day with and without including the PV output power and for the vehicle parks inside or outside. The results indicate that, for each scenario, the number of used TEC modules influences the system performance where the best number varies between 128 and 98. Coupling the PV panel with the TEC system reduces the daily required energy from batteries by about 19%. Running the TEC system during parking from 8 to 10 am decreases the cabin air temperature from 47.5 to 34°C while the input power declines by about 45%, which reduces the interior temperature to 25°C in 10 min (transition time). The contribution of the PV panel based on the studied conditions can increase the range of the vehicle by 10.4 km/day and about 160kWh/year energy saving. The reduction in the input power during transition time reaches 27.8% when the vehicle speed increases from 30 to 60 km/h, while this ratio declines to 10.8% as the vehicle speed rises from 60 to 90 km/h. During vehicle moving, powering the TEC system by the PV panel only can prevent the cabin temperature from rising over 40°C, whereas during parking, there is an optimum fan air velocity that gives the maximum reduction of the cabin temperature.

Investigation of continuous pulse current source on the performance of phase change material-thermoelectric cooler system

In this particle, the influence of phase change materials (PCM) on the property of thermoelectric cooler (TEC) is studied by numerical simulation. The heat sink integrated with PCM is placed on the hot side of TEC to reduce the fluctuation of temperature under a continuous pulse current source. The performance of a single-layer PCM-TEC system with that of a single TEC system under continuous pulse current source is firstly compared. Based on this, the effects of current source type, PCM layer, pulse width, cooling load and pulse amplitude on the cooling performance of TEC are investigated in depth. The results show that, compared to a single TEC system, PCM is able to considerably enhance the cooling performance of the TEC during the phase transition period. Besides, increasing PCM layer or decreasing cooling load improves the phase change interval, which increases threefold when the cooling load increases from 0.02 W to 0.06 W. In addition, it is found that lower temperature can be achieved by increasing pulse width or pulse amplitude.

PERFORMANCE ANALYSIS OF THERMO-ELECTRIC COOLING SYSTEMS EQUIPPED WITH SURFACE-MODIFIED AND RECYCLED NANOFLUIDS

In this research, pure water and recycled nanofluids (RNF) are utilized as heat transfer fluids in the thermoelectric cooling (TEC) system, and the effects of these fluids on the cooling performance are experimentally examined. In order to prevent nanofluid sedimentation and enhance stability, a surface modification process on Fe<sub>3</sub>O<sub>4</sub> particles is performed. With modified Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>-mix-(CH<sub>2</sub>)<sub>3</sub>Cl@Imidazol nanoparticles, water-based nanofluids are prepared at a constant volumetric concentration. This nanofluid is used in a TEC system and recycled. The sonication time is chosen as the experimental parameter in the preparation of RNF. The RNF are subjected to ultrasonication at different time periods, including 3.5, 7, and 14 hours. The temperature drops inside the cooling chamber, coefficient of performance (COP) value of the TEC system, and dimensionless numbers, including Reynolds and Nusselt of nanofluids, are evaluated and discussed in detail. It is determined that the performance of the TEC system can be increased significantly with the usage of nanofluids. Although some deterioration in heat transfer properties is observed for the RNF, these fluids provide a significant improvement in cooling performance compared to pure water. Increasing the nanofluid flow rate increases the cooling chamber performance up to a certain level. Moreover, a significant increase in TEC chamber performance is also achieved by decreasing the temperature of the water bath in the system.

Research on thermal comfort of commercial vehicle and economy of localized air conditioning system with thermoelectric coolers

In commercial vehicles, the power consumption of the traditional air conditioning system used to cool an entire cab is high. In most cases, there is only one driver in vehicle, so adjusting the local thermal environment around the driver can reduce much energy waste. In this paper, a localized air conditioning system based on thermoelectric cooling (TEC) devices was constructed, and its performance characteristic were studied to find the optimal operating conditions in practice. The relationship between the refrigeration power and the operating current of the device was studied. A bench test was carried out to evaluate the performance of the device and the accuracy of the simulation. This paper selected a commercial vehicle cab for the application of the TEC system. The thermal comfort of human body in cab and the economy of local air conditioning system was analyzed by the method of computational fluid dynamics. The driver’s thermal comfort was analyzed based on equivalent temperature and thermal comfort deviation. The results show that when the cooling power is 3000 W, the overall thermal comfort deviation of human body under local thermoelectric refrigeration is 7.94% higher than that under traditional refrigeration. When the duty ratio of the centrifugal fan governor is about 40%–60%, the semiconductor cooling device has excellent refrigeration performance and low energy consumption, which can not only ensure the thermal comfort of the driver but also reduce the energy consumption of the air conditioner.

Design and Performance Evaluation of Thermoelectric Cooling System Integrated with PCM (Phase Change Material)

A thermoelectric system integrated with PCM (Phase Change material) for cooling vaccines has been introduced, thermal management techniques (i) using high performance heat sink on sides(hot, cold) of module (ii) integration of PCM (ice) on cold side were analysed. Experimental results infers that, by adopting water cooled heat sinks at hot side and air cooling at cold side of module, a COP of 0.124 with minimum cooling temperature (Tc) of 6°C (at 130 minutes) is attained by the system. Performance simulations were carried with CFD (computational fluid dynamics) model of system for different heat sink configurations (with or without integration of PCM). Simulation results shows that, (i) in the absence of PCM, a COP of 0.261 and 0.245 is achieved by the system for heat sink configuration of fin and fan on both sides, fin and fan on hot side and fan on cold side respectively, (ii) COP is improved to 0.406 with integration of PCM and is 55.55% higher, considering the same heat sink configuration (fin and fan on both sides), with cooling temperature of 4°C.

Enhanced performance of thermoelectric cooler with phase change materials: An experimental study

The thermal management of a thermoelectric cooler (TEC) has a significant impact on its cooling performance. The heat generated in the hot side of the TEC system reduces the performance and lifespan. Therefore, an efficient thermal management technique is vital for ensuring the TEC to operate at optimum temperature. In this study the performance of TEC is investigated by varying input voltage, air velocity at hot side, heat sink configuration and fill volume of PCM in the heat sink. A 54 W Bismuth Telluride based TEC was chosen for this study and OM35 was used as the phase change material (PCM). The three configurations of aluminium heat sink used in this study are square pocket, rectangle pocket and circular pocket. The input voltage to TEC is varied from 2.5 V to 12.5 V. The results show that, both the cold and hot side temperature of TEC increases when the input voltage is increased. The changes in air velocity at the hot side of the TEC from 1 m/s to 3 m/s reduced the temperature on both the cold and hot side of TEC. Among the three configurations of heat sink, square pocket heat sink with fully filled PCM showed better performance compared to other configurations. Moreover, the heat sink with a square pocket filled with PCM provided cold and hot side temperatures of 27 °C and 58.7 °C respectively when compared to 34 °C and 68.3 °C for the similar operating conditions without PCM. The results indicate that the performance of TEC can be significantly improved by the use of heat sinks filled with PCM.

Numerical study on the effect of solar radiation intensity on the fresh water productivity of solar still equipped with Thermoelectric Cooling System (TEC) for hot and dry areas of Semnan

The fresh water crisis is one of the most important issues in the world and as a solution one of the most important methods of freshwater production is the evaporation of saline water by using of solar stills. Semnan province is one of the largest provinces in Iran. The province covers an area of 97,491 km 2 , which is 5.9% of the total area of the country. This province is the seventh largest province in Iran and is located almost in the central desert region of Iran. Due to its location on the solar belt, the desert areas of Semnan province are prone to the installation of solar cells, and according to the statistics of the General Meteorological Department of Semnan, this province has 325 sunny days in 365 days of the year. Therefore, this area is a great location for using clean solar energy. In this research, using the numerical method, the effect of the presence of the Thermoelectric Cooling System (TEC) on the performance of solar still, intensity and direction of solar radiation has been investigated to check their effect on the rate of freshwater production. The simulations were performed for Semnan city condition with the method of humid air in a three-dimensional, steady and laminar regime by solving the equations of continuity, Navier-Stokes, and water vapor concentration. The results show that there is a direct relationship between radiation intensity and water production rate and increasing radiation intensity increases the amount of produced freshwater. It was also observed that applying a TEC on a part of the glass can increase water production from 15% to 62%. The reason for this increase can be the increase in free convection due to the increase in the flow temperature gradient in designed solar still.

Analysis of Efficiency of Thermoelectric Personal Cooling System Based on Utility Tests.

Thermoelectric modules can find practical application in clothing with a cooling function. A personal cooling system using Peltier modules integrated with clothing was developed and tested with the participation of a person. A dedicated electronic controller was designed that enabled the power or temperature to be controlled and recorded. In the research, the influence of heat sinks and the method of controlling the operation of the module on the cooling efficiency was assessed. The research was aimed at selecting the operating mode of the controller and choosing the arrangement of modules comparing cooling efficiency. The research showed that by selection of appropriate controlling mode, the electric power used can be reduced while keeping the cooling efficiency at the same level. The location of Peltier modules in places where they can tightly adhere to the body increases their performance.

Investigation on the Performance of Solar Still with Thermoelectric Cooling System for Various Cover Material

Investigation on the Performance of Solar Still with Thermoelectric Cooling System for Various Cover Material

Organ Transportation Thermoelectric Cooling System Design and Application

Thermoelectric modules are used in medical devices, air conditioners, refrigeration cabinets, measuring devices, etc. widely used in the fields. Application areas of thermoelectric modules and efforts to increase efficiency are in continuous development. In this study, an organ transport device with the thermoelectric cooling feature, which can be used in the medical field, was designed and performed and performance analyzes were made. An animal kidney measuring 5x6x10 cm was placed in the designed and realized system, and performance analyzes of the system were made at ambient temperatures of 25ºC, 30ºC, 35ºC, 40ºC. Each experiment was repeated five times and the average was taken. It was seen that the system, whose performance analyzes were carried out at different temperatures, was usable. The system's small size, less weight and low cost compared to conventional cooling systems are among the important advantages of the system. It is possible to say that with the further development of the implemented system, larger organs can be cooled and transported and further studies can be carried out in this direction.

Simulation of Minichannel Liquid Based Thermoelectric Cooling System by Changing Dimension of Minichannel and Type of Heat Transfer Fluid

Abstract: In recent time, due to exponential growth in electronic devices there is significant increase in heat dissipating element like integrated circuits(IC), graphical 2Assistant Professor, processing units (GPU) and central processing units (CPU). If there is no proper arrangement for heat removal it can permanently damage whole system. There are several methods used for this, one of which is thermoelectric cooling which works on peltier effect, thermoelectric devices with proper cooling arrangement act like heat pump which removes heat from one side and provide it to another side. The drawback of this system is low efficiency. In this project CFD analysis is done for minichannels of different dimensions along with thermoelectric. Simulation is performed by changing parameters such as hydraulic diameter of minichannel, changing type of heat transfer fluid and mass flow rate of fluid. The study reveals that by optimizing these parameters performance of thermoelectric system can be improved. The aim of this study is to optimize these parameters in order to improve overall heat transfer coefficient and coefficient of performance of the system. Keywords: Thermoelectric cooling, Peltier effect, Minichannel, Overall heat transfer, CFD

Integration of radiative sky cooling to the photovoltaic and thermoelectric system for improved space cooling

The feasibility of integrating the radiative sky cooling ability of common photovoltaic cells into the photovoltaic-thermoelectric cooler to further enhance the space cooling energy density is analyzed in this paper. Specifically, daytime cooling is obtained by the photovoltaic panel powering the thermoelectric cooler while the same photovoltaic panel provides nighttime radiative sky cooling. To achieve an optimal temporal match between the new method’s output cooling power to a cooling building’s time-varying cooling load (with 4 occupants and 24 m2 floor space), two thermoelectric cooler modes of operation are studied; The first continuously operates the thermoelectric cooler power at the time-averaged value while the second directly supplies the photovoltaic power to the thermoelectric cooler in the daytime. Furthermore, a spectral model is used to accurately estimate the radiative energy of crystalline solar cells based on their emissivity spectrum. It is found that radiative sky cooling can almost double the equivalent solar to cooling coefficient of performance over the basic photovoltaic and thermoelectric cooler system (from 0.1099 to 0.2054). The photovoltaic area only needed to be 12–17 m2, and the second operating mode can better match the supply versus cooling demand ratio while yielding a relatively consistent 10 °C difference throughout the entire day.

Optimization of influential geometrical parameters of single slope solar still equipped with thermoelectric system to achieve maximum desalinated water

Solar water desalinators are based on water evaporation and are more important in areas with high evaporation capacity and water scarcity. Today, desalination water performance is improved using various methods. One method is to use a Thermo-Electric Cooling (TEC) system. In the present study, using the numerical solution and humid air method, the effect of the dimensions of single-slope solar still with TEC on water production rate is simulated. The simulation is steady, incompressible, and laminar. To evaluate the effect of desalination dimensions, changes in length, small height, and length of the thermal surface of the cooling system were used. The results show that production in the TEC system is higher than conventional desalination. The trend of changes in water production with increasing parameters of length, small height, and length of the thermal surface of the cooling system is descending, ascending, and ascending, respectively. One of the main reasons for these changes in the number of rotational flows is due to dimensional changes. Meanwhile, in case of increasing the flow velocity due to the increase of free convection, the water production rate will increase. Based on results with a 50 % increase in L, the freshwater production rate was decreased by about 10 %. Also by applying the thermoelectric system a 6.8 % improvement in the freshwater production rate was reported. The main purpose of this study is to increase the efficiency of freshwater production in single-slope solar still by equipping it with a thermoelectric cooling system and also by geometric optimization of solar still.