柴油机活塞-缸套-冷却水系统固流耦合传热研究

Diesel Engine Piston-liner-coolant System Fluid-solid Coupling Heat Transfer

发动机活塞缸套冷却水组成的固流耦合传热系统涉及固体部件传热有限元(FEA)和计算流体力学(CFD)问题。活塞和缸套被燃气加热同时彼此之间发生固体部件传热,缸套又与冷却水进行对流换热。确定上述固体、流体耦合传热系统的内部边界条件成为发动机传热研究的难点。采用耦合分析方法将相互作用的固体部件和流体部分作为一个整体进行研究,计算时可只定义系统外部边界条件。在进行有限元固流耦合传热计算方法研究基础上,对135型发动机中活塞缸套冷却水系统进行数值仿真,试验证明计算具有较高的精度。

Piston-liner-coolant system of engine is a fluid-solid coupled, system which involves solid heat transfer problem and computational fluid dynamics （CFD） problem. Piston and liner are heated by combustion air, and at the same time heat transfer occurs between them, the convective heat transfer between liner and coolant cool the engine. It is difficult to confirm the internal boundary condition for the above fluid solid coupling heat transfer system. So utilize coupling analysis method was used to study the whole system which regarding the interactive solid parts and fluid as an integrated system, defining only the exterior boundary conditions. This method is adopted in numerical simulation of 135 diesel engine piston-liner-coolant system. Calculating results and measuring values are very well accordant.