Analysis And Application Of Oil Bath Lubrication Based On CFD

In the process of transmission, heats which results from engaged gear movement and unavoidable friction may cause gear abrasion and finally decline the working efficiency, so lubrication system which provide both lubrication and cooling for the whole transmission system is very significant. Companies usually choose reversal design strategy which based on the experiment results, however, limited by the experiment methods and research period, CFD simulation seems to be a more voluntary way to assist the transmission design which cost less and last shorter.Combined with a real transmission research program, this paper provides lubrication optimization strategy by using CFD simulation. The main research process and conclusions are listed below:(1)In order to testify if the CFD technology for gear splash lubrication is correct, simplify the complex transmission structure to an rectangle box and a pair of engaged gear. Design the experiment and build the experiment equipment, using the high speed camera to capture the process of oil splash.(2)Simulate the experiment in the same boundary condition in CFD software, compare the oil movement with the experiment results, describe the phenomena and analysis the difference. The research above proved that the CFD method could obtain the oil movement happened in real, so the CFD setups are settled and the post strategy dealing with the CFD date is clear.(3)More models are settled and testified in CFD to obtain the law that how oil temperature and gear immerged depth affect the oil splash. Based on the results, temperature would change the whole oil quality, increase the gear area covered by oil and decline the oil slick on the gear; gear immerged depth could greatly promote both the gear lubrication and velocity loss. By collect all the CFD message, curved surfaces which related to the oil and temperature and gear immerged depth are given to provide estimations for other lubrication conditions.(4)Finish the real transmission simulation and estimate the whole lubrication conditions, find out the parts in short of the lubrication and optimize the problem. The optimization strategies are offered in two ways: structure optimization and the oil level height promotion, finally the simplified models proved that both the optimization strategies are effective.By doing research above, the whole paper conclude the experiment design, simulation testify, law study and engineering apply, not only the CFD technology is proved correct, the influences of the oil splash are discussed, but the real transmission lubrication efficiency is also optimized. This paper has some engineering instruction for transmission lubrication system design.