发动机冷却系统中流动与传热问题数值模拟进展

着重论述利用数值模拟技术研究发动机冷却系统中流动与传热问题的发展现状，包括水套单相流及气液两相流流动、流－固耦合传热、一维与三维联合模拟等该研究领域的热点内容。耦合系统之间联合分析的方法准确反映了发动机各部件之间的影响关系，这种分析方法是目前研究的重点，但其中仍存在一些问题。基于此状况提出改进办法：针对不同工况选用循环平均参数作为燃气侧传热边界条件；水套进出口的流动边界条件，在稳态工况下设为定值，在过渡工况下通过循环一维仿真计算确定；应采用整体耦合方法进行计算，计算模型应尽量完整，但可以进行适当的简化，并总结出模型简化的原则。

Development of Numerical Simulation on Flow and Heat Transfer in Internal Combustion Engine Cooling System

The development of research on flow and heat transfer in internal combustion engine cooling system using numerical simulation technology is summarized, including the popular investigations on single phase and gas-fluid two phase flow in water jacket, fluid-solid coupled heat transfer, 1D and 3D co-simulation, etc. Among these investigations, the coupled systems co-simulation accurately reflects the influence relations among internal combustion engine parts. These influence relations are research emphasis at present, however some problems still exist therein. On the basis of this situation, the improvement methods are put forward. In view of different working conditions, circulation average parameters are used as the heat transfer boundary condition of combustion side. The flow boundary condition of water jacket inlet and outlet is set as a fixed value under steady working condition, or it is determined through circulation 1D simulation calculation under transit working condition. For the calculation, integral coupling method should be used, and the calculation model should be complete as far as possible, but it may be simplified appropriately. The principle of the model simplification is summarized.