An quantitative analysis for unsteady partial-EHL and experimental discussion

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The purpose of this study is to get a useful analysis model for dynamically loaded mixed lubricated machine elements with concentrated contact. In this report, a new numerical model has been developed and some experiments have been done to obtain the prosperity of the model.First, a steady state analysis based on thermal elast-hydrodynamic mixed Lubrication theory (TEHML) is introduced. It considers thermal effects of lubricant visco-elasticity and heat at contact area. In this analysis, not only equations of the elast-hydrodynamic mixed lubrication (EHML) but also energy equations of lubricant film are used. Results of pressure, temperature distribution and friction coefficient are presented. Results of this calculation are compared with those of normal EHML,so film thickness by TEHML calculation is more thin than that by normal EHML calculation. At low slip ratio, friction of TEHML calculation is more large than that of normal calculation. It means thermal calculation for dynamically loaded mixed lubricated machine elements with concentrated contact is important.Second, for example of dynamically analysis, friction and lubrication between cam and follower has been calculated including equations of motion of cam, and squeeze effect for lubricant film. In this calculation, At the point near cam nose where the load significantly changes, the effects of fluid adiabatic change can not be neglected.Cam and follower friction experiments has been done to valid the calculations. Friction of caluclations accord with that of experiments. But the test equipment (type I) was not enough rigid, it was influenced natural vibration, so type II equipment has been developed.