Analysis And Optimization Of Thermal Comfort Of Passenger Compartment In A Passenger Car

With the development of modern science and technology and the improvement of people's performance requirements for automobiles,the technology of automobile industry has undergone tremendous changes.Now people pay attention to the performance of cars more in favor of safety,comfort,energy saving,environmental protection and so on.China has put forward the call for energy saving and emission reduction in the automobile industry,and increasing the air conditioning displacement has not met the production requirements,so studying the influence of different wind delivery parameters on the flow field in the occupant compartment has a heavy lifting effect.There are two kinds of test methods and numerical simulation methods in the study of internal flow field,but because the test method is more affected by objective factors,and the cost is large,the time is long,which is not conducive to the rapid progress of R&D work.The numerical simulation method is greatly influenced by the objective factors,the external factors that affect the thermal comfort of the passenger compartment are all considered,the fluid boundary constraint is accurately given in the Solver Fluent software,and then the air supply parameters are set by using the control variable method,which can simulate the different flow of gas in the passenger compartment.Aiming at the simulation results,the optimization scheme is put forward,and the design of air conditioning pipeline is optimized,so as to improve the heat comfort of the occupant.This paper takes the passenger compartment of a domestic MPV passenger car as the research object,and the main research contents are as follows:1?This paper makes a comprehensive analysis of the source of heat source in the passenger compartment,and discusses the relevant parameters and the establishment of the thermal equilibrium equation.2?The finite element model of the internal structure of the passenger compartment is established by using UG software,and the reliability of the model is verified by the relevant tests.And then the finite element model is used for reasonable geometrical pretreatment and 2D surface mesh,and then the 3D body mesh is divided by ICEM and a reasonable boundary layer is generated.3 ? Choosing reasonable boundary conditions,quantitatively and qualitatively analyzing and discussing the thermal comfort of the occupant in the occupant cabin,using the equivalent temperature to analyze the thermal comfort of the occupant cabin is the indoor occupant,find out the shortcomings,summarize and put forward a set of air conditioning pipeline optimization scheme based on the adaptive body mesh deformation.4?Using Isight to integrate Sculptor and Fluent,the front-row air conditioning pipeline model is combined to optimize the simulation,using the optimized Latin side test method,after 800 iterations of the comparison and analysis,the optimized air conditioning pipeline pressure area,than the optimization before the increase of about 15%,And the uniformity is good,the maximum wind speed of the outlet is improved by about 5% before the optimization,the speed gradient change is also more flat,the optimized air conditioning pipeline airflow is smoother,and finally the optimized air conditioning pipeline model is determined.Through the research of the subject,the thermal comfort of the occupant in the passenger compartment is analyzed by using the optimized front-row air conditioning pipeline model,and the equivalent temperature before and after the optimization of the front occupant is compared.The results show that the equivalent temperature of most segments of the optimized front-row occupant's body has been slightly reduced,and the expected effect has been achieved.The equivalent temperature of the front passenger's hand dropped by approximately 2.3?,falling within the comfort temperature range.Although the equivalent temperature of the legs and feet is reduced by 2.6? and 1.6? respectively before optimization,the thermal comfort of the segment is still above the highest temperature of the equivalent temperature.As can be seen from the whole,the passenger cabin's front passenger occupant's thermal comfort has been improved,the optimization effect is considerable,and the optimization scheme is feasible.