Design And Research On Cooling System Of Concentrated Perovskite Tandem Solar Cells

Under the current energy situation,solar photovoltaic power generation technology is booming,and the concentrating perovskite tandem solar cell can greatly improve the utilization rate of light energy and reduce the cost,so it has a good application prospects.However,with the continuous improvement of the industrial level,the concentrating multiples of solar cell can achieve is far greater than before,and the temperature of the cell has risen sharply.If the accumulated heat cannot be dissipated in time,it will have a harmful impact on the performance and life of the battery,so it puts forward higher requirements on the heat dissipation of the battery.For the above problems,deionized water was used as the cooling medium,and an array fin type channel coupled jet cooling system was designed in this paper.It integrates the advantages of micro-channel heat dissipation and impinging jet heat dissipation,and has the advantages of strong heat exchange performance and good temperature uniformity.The flow and heat transfer characteristics of the array fin channel coupled jet heat sink are studied by numerical simulation combined with experiment.The specific research contents and conclusions are as follows:（1）Using numerical calculation method,the effects of jet height-diameter ratio H/d,channel aspect ratio H_L/W,pumping power P_pumping and other parameters of the array fin channel-coupled jet heat sink on the heat transfer performance of heat sink were investigated.Compared with the micro-fluid heat sink,it is found that the structure of coupling the jet with the array fin channel has a better heat transfer performance,and the reasons are further analyzed.（2）The numerical simulation results showed that increasing jet Reynolds number Re_a promotes the heat transfer intensity of the heat sink.H_L/W has an obvious impact on the heat transfer performance of the heat sink,at Re_a>2296.22,the optimum channel aspect ratio H_L/W=0.25.The pumping power P_pumping is one of the main factors affecting the performance of the heat sink,at P_pumping<0.15W,the decline rate of the heat sink thermal resistance R_b is fast,when the P_pumping is higher than 0.23W,this trend becomes gentle.Under the same condition,the smaller the H/d,the better the heat transfer effect.In the paper,at Re_a=3538.77,H/d=2,the heat transfer performance of the heat sink is the best.（3）On the basis of the previous simulation,an experimental system was built around the array fin channel coupled jet heat sink,the heater was used to simulate the heating power of the concentrating perovskite tandem solar cell,and the heat sink was experimentally studied.The results showed that the input heat flux Q on the performance of the heat sink and pressure loss（35）P can be neglected.And experimental jet Reynolds numbers Re_a were in the range of 1590 to 3540,when H/d is constant,h,Nu and（35）P monotonically increase,heat sink thermal resistance R_b monotonically decreases.When Re_adoubled,Nu increase by about 50%.Under the ultimate working conditions of the experiment were H/d=9,Re_a=1590.46,Q=540 W（The heating power of solar cell under the condition of about 782 times the concentration ratio）,the energy utilization efficiency of the heat sink is the highest,and the temperature does not exceed the limit working temperature of the battery.The experimental results are in good agreement with the simulation results,the maximum errors of the average temperature T_w and the average convective heat transfer coefficient h are 2.12%and 4.59%,respectively,while thermal resistance R_b and pressure loss（35）P are 4.4%and 9.5%,the deviation are reasonable,these verify the accuracy of the simulation results.These conclusions provide data support for subsequent structure optimization and performance studies of the heat sink.