Simulation study of flow and heat transfer in oscillating cooling pistons based on CFD

Piston needs to be cooled efficiently with increase of thermal loading of diesel engines. In this paper, the simulation study on transient heat transfer in the oscillating cooling pistons were conducted by using the computational fluid dynamic (CFD) method, the behavior of oil filling ratio and wall heat transfer coefficient versus crankshaft angle at different rotation speeds were obtained. The results show that oil filling ratio is decreased and wall heat transfer coefficient is increased as increasing engine rotation speed. The enhanced heat transfer of cooling gallery top and bottom caused by oil oscillating and impingement is higher than side walls. The results can provide boundary conditions for the finite element analysis (FEA) of piston, and provide references for optimizing the piston in concept design stage.