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The performance of solar photovoltaic (PV) panels is significantly affected by their operating temperature, with higher temperatures leading to decreased efficiency and reduced lifespan. This study explores the enhancement of PV panel performance through the implementation of an advanced cooling technology that combines Phase Change Materials (PCM) with forced convection. The PCM layer, strategically placed at the back of the PV panel, absorbs and stores thermal energy during periods of high solar irradiance, while the forced convection system actively dissipates excess heat. A comprehensive simulation of this hybrid cooling system is conducted using ANSYS software. The simulation involves creating a detailed 3D model of the PV panel, assigning appropriate material properties, and setting up transient thermal analysis to capture the dynamic thermal behavior throughout a typical day. The results indicate that the integration of PCM and forced convection significantly reduces peak temperatures of the PV panels, thereby enhancing their efficiency and potentially increasing their operational lifespan. This innovative cooling solution presents a promising avenue for improving the performance and reliability of solar PV systems. The ANSYS simulation results reveal that the combined PCM and forced convection cooling system effectively reduces the peak temperatures of the solar panels. This temperature reduction significantly improves the electrical efficiency of the panels and suggests the potential for extending their operational life. The study confirms the feasibility of this hybrid cooling method as a practical and effective solution to enhance the performance and reliability of solar panel installations, paving the way for more sustainable and efficient solar energy systems. [ABSTRACT FROM AUTHOR]

Conventional straight fin (SF) radiators have difficulties meeting the cooling requirements of high-power electronic components. Therefore, based on the structure and technology of the detachable fin radiator, this paper proposes a kind of radiator embedded in the heat pipe base and uses the roll-bond flat heat pipe (RBFHP) to replace the traditional fin. The radiator has the advantages of modularity, easy manufacturing, low cost and good heat balance. In this study, the heat pipes (HPs)-RBFHPs radiator was tested in natural convection and forced convection to mimic the actual application scenario and compared with the conventional aluminum radiator. Heating power, angle, wind speed and other aspects were studied. The results showed that the cooling performance of the HPs-RBFHPs radiator was improved by 10.7% to 55% compared with that of the SF radiator under different working conditions. The minimum total thermal resistance in the horizontal state was only 0.37 °C/W. The temperature equalization of the base played a dominant role in the performance of the radiator at a large angle, and the fin group could be ineffective when the angle was greater than 60°. Under the most economical conditions with an inclination of 0° and a wind speed of 2 m/s, the input power was 340 W, the heat source temperature of the HPs-RBFHPs was only 64.2 °C, and the heat dissipation performance was 55.4% higher than that of SFs. [ABSTRACT FROM AUTHOR]

Conventional straight fin (SF) radiators have difficulties meeting the cooling requirements of high-power electronic components. Therefore, based on the structure and technology of the detachable fin radiator, this paper proposes a kind of radiator embedded in the heat pipe base and uses the roll-bond flat heat pipe (RBFHP) to replace the traditional fin. The radiator has the advantages of modularity, easy manufacturing, low cost and good heat balance. In this study, the heat pipes (HPs)-RBFHPs radiator was tested in natural convection and forced convection to mimic the actual application scenario and compared with the conventional aluminum radiator. Heating power, angle, wind speed and other aspects were studied. The results showed that the cooling performance of the HPs-RBFHPs radiator was improved by 10.7% to 55% compared with that of the SF radiator under different working conditions. The minimum total thermal resistance in the horizontal state was only 0.37 °C/W. The temperature equalization of the base played a dominant role in the performance of the radiator at a large angle, and the fin group could be ineffective when the angle was greater than 60°. Under the most economical conditions with an inclination of 0° and a wind speed of 2 m/s, the input power was 340 W, the heat source temperature of the HPs-RBFHPs was only 64.2 °C, and the heat dissipation performance was 55.4% higher than that of SFs.

This paper explores the potential of forced convection cooling in a ducted photovoltaic façade unit. Where a photovoltaic panel is backed by a 5 cm thick insulated duct at a depth of 50 cm. The potential of heat removal from the photovoltaic unit due to forced convection is investigated with a range of fan speeds from 1 m/s to 6 m/s. It is found that the ΔT between the inlet and outlet of the duct ranged from 2.6–24.6 °C. A fan speed of 4 m/s yielded the highest cooling potential by removing 550 W with a cooling efficiency of 51%. Whereas a fan speed of 6 m/s yielded the lowest mean PV cell temperature of 62.7 °C. This would improve the cell's efficiency by 17.53%. This very experimental setup has been tested previously with natural convection cooling, which removed 529 W with a maximum efficiency of 48.98% This improves PV panel efficiency by 12.69%. The addition of heat removed and power recovered by the ducted system was 68.53% of the former (i.e., forced convection), while it was 61.67% for the latter. A 12 V DC fan with a variable speed electric circuit powered by a fraction of the PV generated power (i.e., 0.75 W) yielded better cooling that translated into nearly 19 W of further energy generation. [ABSTRACT FROM AUTHOR]

In the geyser boiling mode, the working fluid state is divided into a boiling process and a quiet process, and the sodium-potassium (Na-K) alloy heat pipe can discontinuously transfer heat at each boiling. The overheating of the liquid working fluid at the bottom causes short-term boiling and forms slug bubble, the strong condensing ability quickly conducts heat from the evaporator section. And geyser boiling can occur before the working fluid forms continuous flow, so it transfers more heat at lower temperatures than natural convection cooling. In this study, the heat transfer process of a Na-K alloy heat pipe with forced convection cooling under different heating power was experimental studied. The geyser boiling mode can make the Na-K alloy heat pipe work below 650 °C and reduce the start-up time. In the process of geyser boiling, the heat transfer quantity was increased by the boiling frequency and the amount of vapor produced in a single boiling. The boiling temperature had no obvious change with the increased of heating power, and the condenser section temperature increased with the heating power.

In this paper, a theoretical model is developed to investigate the performance of the hybrid solar thermoelectric generator (HSTEG) system, which is designed without (B-HSTEG) and with an evacuated glass tube (V-HSTEG). The heat loss, power output, thermal efficiency, and electrical efficiency of the B-HSTEG/V-HSTEG system are evaluated by analyzing the design parameters such as geometric solar concentration ratio, thermoelectric figure of merit, and cold-side inlet fluid temperature. The performance of the B-HSTEG is compared with the V-HSTEG system using two heat transfer fluids: water and Therminol VP-1. The maximum electrical efficiency of the B-HSTEG and V-HSTEG is estimated to be 12.2 and 15.6% (ZT = 3) with a corresponding thermal efficiency of about 61.9 and 60.3%, respectively. Overall, this paper provides a systematic performance analysis of HSTEG systems. [ABSTRACT FROM PUBLISHER]

This paper introduces a joint charge and thermal management problem for batteries in a battery–supercapacitor hybrid power source of a portable system, which has been equipped with a forced convection cooling technique, such as a fan. A key consideration in such a system is that the battery aging depends strongly on the battery temperature, which is in turn a function of the workload running on the device and the control policy for the fan. More precisely, this paper presents a hierarchical algorithm for maximizing the battery lifespan under given workload conditions. The algorithm relies on a combination of reinforcement learning and dynamic programming techniques. Simulation results show that the proposed algorithm achieves up to 2 \times improvements in battery lifespan, resulting in completion of up to 80% additional workload before the battery expires. [ABSTRACT FROM AUTHOR]