This paper was produced for the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

This paper uses the results of a publicly available paper which validates mesh based computational fluid dynamics (CFD) methods for predicting oil flow in a closed gearbox to compare the same results for a particle based numerical method. In the original paper a standard FZG no-load power loss test rig containing a wheel and pinion partially submerged in oil was used. Multiple types of oil were each tested at several rotational rates to gather qualitative images of oil distribution and churning power losses. These results were then compared to numerical simulations performed in Ansys Fluent 18.0. The authors found good agreement between experimental and numerical results. To further the work a similar model was created in Particleworks, a CFD tool which utilizes the Moving Particle Simulation (MPS) method. MPS is a specialized solver developed at the University of Tokyo in 1996 which is applicable to incompressible, free surface flows. The method discretizes a fluid volume as a collection of free moving, discrete particles and the walls as boundary functions. There is no meshing required which can save time in the pre-processing stage, making it attractive for problems with complex geometry. There is little performance penalty for adding motion to boundary walls so it is very applicable to gear motion, which typically requires expensive remeshing steps for more traditional CFD methods. This was tested by comparing simulation time and accuracy with the flow distribution results in the original paper. It was found that there was good agreement between the simulation results and experiment, while achieving results in a far shorter time and traditional CFD.