Study On The Characteristics Of Temperature Rise And Ventilation Cooling In Passenger Compartment

The ownership of car in China is increasing,while the development of supporting transportation facilities are relatively backward,most of the existing parking lots are open-air and the parking spaces are insufficient,many cars can only park on the side of the road.Cars parked in the open air are directly exposed to the strong sunlight,causing a high temperature in the passenger compartment and seriously affecting the passengers’ driving experience in the summer.To reduce the temperature of the passenger compartment and improve the thermal comfort of the passengers,this paper studies the influence of different factors on the temperature distribution of the passenger compartment and uses the the automobile air conditioner to pre-cool the passenger compartment.In this paper,the outdoor parking temperature rise test was first conducted on the test vehicle,and the test environment parameters are obtained,which are used as the boundary conditions of the subsequent simulation.Then based on the principle of the temperature rise of the passenger compartment,the vehicle body surface convection heat transfer coefficient,the equivalent heat transfer model of the passenger compartment,the solar radiation model and the air properties were set.The simulation calculation of cabin temperature rise was carried out,comparing with the test results,the accuracy of simulation results is verified.The law of temperature distribution of passenger compartment was obtained by studying the influence of greenhouse effect,different parking time and different parking direction on the temperature distribution of passenger compartment.Based on the thermal environment of the passenger compartment,the average cooling rate was established by using the automobile air conditioner for cooling.The cooling effect of different air supply and air supply angles were evaluated,and the rules of cooling were summarized,which provides a reference for the design of the pre-cooling function of the the car.The final results show that under the same solar radiation intensity,the overall temperature of the passenger compartment was increased while the greenhouse effect was considering.The areas close to the front windshield,such as front seats and dashboards,are much more affected by the greenhouse effect.Adjusting the parking direction of the car can significantly reduce the thermal load of the passenger compartment,turning the car to the north or east can reduce the temperature of the passenger compartment during the time that the solar radiation is the strongest in summer.Ventilating in advance can reduce the temperature of the passenger compartment,for the air,the cooling effect is mainly determined by the air supply volume,while the air supply angle has limited influence on it’s cooling effect,for the main driver’s seat,adjusting the air supply volume and air supply angle can increase the cooling effect.