Analysis Of The Thermal Comfort In Vehicle’s Cabin

With the development of economy and society, vehicles become the necessary means in daily life, which makes people’s life more convenient. And at the same time, people have more requirements about environmently comfortableness in the vehicles. The environment in the vehicles affects the normal driving and driver and other passengers’ state of mind directly. A comfortable and quite environment can make the driver and passengers have a good feeling of the physiology and psychology. To meet thermal comfort requirements inside, it has need to maintain air humidity, temperature, air velocity, and air cleanliness, and so on, in the thermal comfort standard range of human. As changing in the external environment, air humidity, temperature and other environmental parameters will also change accordingly. To keep all parameters in the scope of human’s thermal comfort in the vehicles, the air conditioning system plays a very important role.Firstly, it introduces the history and current situation about the study on thermal comfort in vehicle’s cabin in this paper. Then, it aslo introduces the definition, application and related accessing means of 5 evaluation standards of thermal comfort in detail, which provides bases for evaluation and analysis thermal comfort in vehicle’s cabin after. And then, it also explains the main selected mathematical model, geometry cleanup, meshing, boundary conditions’ setting, etc. Finally, it does simulation calculation the heating and cooling modes respectively. In this paper, it selects two reference sections, divides the each person’s body into 14 parts, and selects one point on each part to monitor respectively. With the reference sections and points, it can monitor air velocity, temperature, relative humidity and mean radiation temperature to analysis and evaluate the thermal comfort in vehicle’s cabin, then gives corresponding suggestions. In this paper, it chooses the thermal comfort module in Star ccm+, which divides the person’s body into four layers structure: center, muscle, fat and skin. As the external environmental factor, the solar radiation is also considered, which makes the final simulation results more accurate.With analyzing the distribution of velocity field, temperature field, mean radiant temperature and relative humidity under refrigeration and heating modes, it shows that thermal comfort in overrall cabin is good, except the area around the feet, legs, face and neck of the passengers in front, and the area around the body of the passengers in back, especially their feet and legs. Open the air ports of air conditioning near the feet of front-seat passengers, and increase air supply inlet near the back-seat passengers’ body, which can improve the condition of air supply to improve the thermal comfort in the whole cabin.Study on thermal comfort in vehicle’s cabin has become an important topic in the auto industry, which meets the current requirements of resource saving and environment-friendly. It also become an important means to improve the markecompetitiveness for major car manufactures, and is the only way for the healthy development of automobile industry in the future. This paper is more accurate and realistic reference value for engineering application of study on thermal comfort in vehicle’s cabin.