The Effect of Surface Energy and Particle Size on Smooth Particle Based Lubrication Simulation
13242
08/18/2022
- Content
Lubrication system modelling is a critical aspect of transmission development, effecting the unit cost, thermal performance, efficiency, reliability and NVH of the system. For many emerging transmission systems, there is a focus on lubricant volume reduction for minimising the system weight, unit costs and churning losses. This not only presents difficulties for the system thermal performance at high speed and power, where maximum total power loss can create an overheating of the system, but also for localised overheating during start stop or creeping. Here the subtleties of the lubricant flow and component wetting are critical to accurately predicting the component lubrication, particularly for components at the top of the transmission. For accurate modelling of the lubrication in the system, smooth particle based CFD offers a fast and effective solution. For the simulation of the finer aspects of the lubricant flow is becomes essential to tune the particle characteristics (particle size and surface energy) to ensure the correct lubricant wetting and flow through the system is captured. An investigation of the correct lubricant characteristics will be presented with comparison to real transmission lubrication under the same conditions to validate the optimised parameters. It will be shown that without the correct setting of the lubricant simulation parameters, an optimised lubricant fill level cannot be determined.