Simulation And Design Investigation On Thermal System Of Vehicle

This thesis develops the method for analysis of the thermal feature, and presents the design method for the thermal system of vehicles. According to the structural features and the external condition of vehicles, the theory of heat transfer is applied to establish the 3-D transient temperature field. The model is solved by the way of finite difference method. On the basis of the temperature model of vehicles, the thermal system is designed.While designing the thermal system of vehicles, an equation for calculating air conditioning's load is worked out from the lumped parameter method. The cooling system's load is relative to the dispersed heat of engine, gearing and so on. The cooling system's design is consist of laying out cooling system, distributing and adjusting cooling air, the design of fan and radiators. The air-conditioning system's design includes selection of compressor, expand valve, condenser and evaporator.Based on the design of the cooling system, In the course of computing the total temperature field, Monte Carlo method is put forward for computing the angle factor and the projection area. Procedure can compute the angle factor between any two surfaces, includes plane, circularity, cylinder, sphere and taper. Furthermore, the working process of the diesel engine is simulated. The dispersed wet and metabolic heat of people and instruments in the driver's cabin are taken into account.Additionally, the author improves on a set of computer-aided design software designed before that provides the methods of the total thermal system's design for the proper motion artillery, involves improvement of the thermal model, improvement on the computation methods of the temperature fields, foundation of heat transfer in the diesel engine, etc. By using the developed programme, the temperature distribution of vehicles could be simulated and the thermal system could be designed. The results are analysed and discussed in detail.