Thermal Simulation And Air Cooling Design Of Electric Aircraft Engine Compartment

Due to its simple structure,clean and pollution-free,etc.electric aircraft has shown a broad application prospects and potential in the field of general aviation.There are still many engineering problems to be solved as far as the current technical level is concerned.During the operation of the aircraft,motor,controller and various accessories,auxiliary equipment will produce heat.Because the aircraft motor compartment is a relatively small space,it will cause the air in the engine compartment to be continuously heated and the temperature in the compartment will become higher and higher.The service ability,service life and safety performance of each component of the electric power system would decreas.If the thermal performance of the engine compartment is not good,gas flow in the cabin could not be fluent.Therefore,it is very important for long time operation of the aircraft to launch a thermal simulation of the motor compartment and to design a reasonable cooling solution.In this thesis,Rui Xiang two-seat electric light aircraft has been taken as the research object.To solve the poor heat dissipation performance of the engine compartment,the internal structure,heat generation mechanism and heat transfer characteristics of the engine compartment have been analyzed based on the theory of heat transfer and fluid mechanics,and the temperature field and flow field distribution in the engine compartment of the aircraft were simulated and analyzed by CFD software.In the simulation process,the adopted turbulence model is the ‘κ-ε’ two-equation turbulence model,and the air in the cabin is assumed to be three-dimensional steady turbulent flow and the fluid is incompressible,the heat source is defined by the specified wall heat flux.The simulation results show that there are some problems such as uneven heat dissipation and excessive local temperature on the surface of heat source under the existing cooling system.Considering the characteristics of the flow field both the engine compartment’s inside and outside and its own structural characteristics,seven optimization schemes have been proposed based on the original air-cooling scheme,and modeling and simulation were carried out separately,by comparing the simulation results,the optimal air cooling scheme is selected.