Thermal Comfort Analysis On Internal Air-flow Field Of Car Cabin

The thermal comfort of crew cabin is one of the most important factors which influence the whole comfort of car. It has important influence on the health of the vehicle occupant and driving safety. It is a challenging task to realize the thermal comfort of crew cabin, the overall design of air conditioning system assembly of ventilating duct, cabin air-flow field, "heating ventilation and air conditioning" and control strategy are approached. The flow field analysis of crew cabin is the most important component in the design of air-conditioning system. On the one hand, it decides the thermal comfort of occupant and influence the performance and energy consumption of air conditioning system. On the other hand, The results of crew cabin heat load decides other parts of the system.Previous occupant compartment design and analysis of the flow field are based on real vehicle test basis, but nowadays Virtual Product Development (VPD) has run through every stage of the design process. Therefore in the design process of the air conditioning system on the need to establish an efficient, low-cost simulation analysis method to optimize the flow field crew compartment, and air conditioning systems and make the rest of the design process to pass data to each other.This paper attempts to establish a suitable car occupant thermal comfort evaluation system. Summed up in the passenger compartment under the impact of non-uniform thermal environment of the main occupant thermal comfort index parameters; analyzed the thermal environment are commonly used in the evaluation of thermal comfort is forecast to Predicted Mean Vote(PMV) and the Equivalent Temperature (EQT); drawing on the basis of the above two methods is proposed for the passenger compartment thermal environment is easy to use in the air conditioning control thermal comfort evaluation.Second, given a reverse air-conditioning system heat load calculation. Analysis of the automotive air conditioning heat load characteristics; comparing the theoretical automobile air conditioning load calculation methods; identified simulated summer car air conditioning and refrigeration environmental parameters; given heat load analysis for simulation reverse calculation method.Then in the general analysis software Fluent, based on the establishment of a passenger occupant compartment containing the flow field simulation model; given model boundary calculation methods and settings; respectively, for the crew cabin air velocity field, temperature field, pressure field to analyze.Finally, the simulation model established in this paper were the four work modes and two air-conditioning heat and speed combination is simulated under different conditions and gives the occupant thermal comfort evaluation method of calculation results with reverse air conditioning system heat load. Results of the analysis on the car air conditioning system design has a certain reference.