Numerical Analysis Of Air-flow Field And Temperature Field In A Passenger Compartment

Thermal environment was observed in a narrow passenger compartment in vehicle which has major impact not only on passenger comfort, but also on physical and mental health. This influence was showing through compartment airflow, such as temperature field and velocity field. Thermal environment in a passenger compartment was regulated by air-condition. Numerical simulation was an intuitive and effective way to study the airflow characteristics in the passenger compartment.In this issue, firstly, current research situation about flow distribution in passenger compartment, the theory of numerical simulation and the method of partition gridding were introduced what were necessary foundation for the modeling and numerical simulation. Secondly, three-dimensional models were established using GAMBIT. Then using the CFD software FLUENT numerical simulation were carried on in multiple working conditions. Finally, the influence of different velocity, temperature and distribution angle in passenger compartment velocity field and temperature field were analyzed according to the results, and further analyzed flow field characteristic considering the seat gap and door gap.Conclusions:Firstly, when the air supply velocity increases, the temperature will reduce and the velocity will increase. Secondly, when the air supply temperature increases, the temperature will elevate and the velocity field will be nearly invariable. Thirdly, changing the air velocity and temperature from the middle vent can improve the thermal comfort of the rear compartment. Fourthly, the air angle has a great impact on air-flow field and temperature field, when the air angle is between 30°and 45°, the distribution of velocity and temperature field in compartment is better than the situation that the air angle is horizontal. Finally increasing the distance appropriately between seat and wall can induce a rational distribution of temperature and velocity field of the rear compartment; the influence of door gaps in temperature and velocity field cannot be ignored when the car is running, because encapsulation is not good, the air will come into car. So we have to consider the air of this part when calculating refrigeration duty. Otherwise, we will decrease the refrigeration effect of air-conditioning.