Experimental Study And Numerical Simulation Of Mesoscale Combustion Driven Thermoelectric Generation

With the continuous improvement of China’s economy and technology,the energy problem is becoming more and more serious.Recently,the country has put forward new requirements for carbon neutralization,new energy vehicles and the Internet of things.At present,most of the mobile power systems are lithium-ion battery systems,which have low energy density and long charging time,making the problem of power supply for new energy vehicles,UAVs and other mobile devices more prominent.A thermogenerator driven by mesoscopic combustion is designed in this paper.Based on the Seebeck effect,by burning propane gas,the thermal energy generated by combustion is directly converted into electric energy by using a micro thermoelectric generator.This paper includes the following points:(1)A new micro thermoelectric generator burner was designed.First of all,using the multi-step structure,the flame can adapt to the combustion position and keep the combustion stable.Secondly,the counter current heat transfer technology is used to enhance the overall heat transfer capacity and preheat the unburned gas.Finally,pin fin is used to enhance the heat collection effect.(2)The performance of the thermoelectric generator is tested by using the traditional bismuth telluride thermoelectric module.Including different chemical equivalence ratio,combustion power,cold end heat dissipation,wall insulation and other conditions.When the stoichiometric ratio is 0.95,the combustion power is 28.3 W,and the wall is fully insulated,the overall power generation is the highest(29.6 w),and the power generation efficiency is the highest(2.84%).In the scope of the study,the improvement of the cooling power of the cold end leads to the decrease of the power generation efficiency.(3)In this paper,the hybrid structure of a new type of bismuth telluride lead telluride thermoelectric generator and a traditional bismuth telluride thermoelectric generator is used to study the power generation performance of a micro thermoelectric generator under different combustion power,chemical equivalence ratio and cold end heat dissipation conditions.It is found that the maximum power generation of the system is 51.0 W,which is 72.3% higher than that of the system with bismuth telluride thermoelectric module(29.6 w).(4)The difference between the temperature of the hot end wall and the actual measurement value of the collector is studied by using the software gambit and fluent.It is found that the simulated temperature is slightly higher than the actual measurement value,and it is concluded that some of the fuel unburned results in the temperature reduction and some measurement errors.In addition,the research shows that the burner designed in this paper can preheat the unburned gas effectively,thus increasing the stability of the system.