Research On Cooling Performance Of Cylindrical Exhaust-Based Thermoelectric Generators

In order to ease the energy contradiction problem,except for the research of new energy vehicles,some new technologies about the energy conservation are also studied and discussed,and one of them is the exhaust-based thermoelectric generators(TEG)technology.On the basis of thermoelectric effect,TEGs could complete the conversion from the heat contained in the exhaust to the electric power,so that the energy can be recycled used and the energy utilization is promoted.Therefore,the TEG technology is thought to have a good development prospect as well as the research value.In addition,as one of the key points which determinate the output power of the whole TEG system,the cooling device plays a significant role in power generating.Based on the hydrodynamics and heat transfer theory,a research on cooling performance of the cylindrical TEG is carried through the methods of numerical simulation and experiment.In the first,in order to obtain the boundary conditions performance and validate the simulation results,the performance test bench of cylindrical TEG is built,and the temperature distribution on heat exchanger is gained.In addition,the temperature difference as well as the pressure drop between inlet and outlet of the water tank are all collected.Then,two different types of cooling unit are proposed,modeled and simulated,which are the semi-circle type water tank and the stripe type water tank respectively,and the differences on convection heat transfer and fluid resistance between the them are discussed.Meanwhile,from the point of view of cooling effect and power consumption,a new index is defined to evaluate the comprehensive performance of the two water tanks.After that,the fins are added inside the water tank to enhance the heat transfer between the fluid and the wall,and the layouts as well as four different shapes of fins in the non-flat channel are compared to analyze the influence on convection heat transfer and fluid resistance.In the end,based on the radial basis function neural network model,the optimal Latin hypercube and the multi-island genetic algorithm,the change laws between the geometries of fins and the average Nusselt number as well as the friction factor of the interface are all analyzed,and the optimal combination of parameters is also gained.Finally,the optimal result shows that the average Nusselt number as well as the friction factor increased about 42.5% and 9.3%,respectively,and lead to a 27.8% improvement of the comprehension efficiency coefficient.As the result shows,compared to the stripe type water tank,the convection heat transfer intensity as well as the fluid resistance of the semi-circle type water tank are both higher,and the comprehensive performance is also a little bit of better.On the other side,for the fins inside of the cavity,it is found that the comprehensive efficiency factor is highest when the fins are arranged both on the upper and lower side of the interface,and the performance of rectangle fins is best among four kinds of fin shapes.