Isothermal Elastohydrodynamic Lubrication Research Of Skew Roller Pairs

Isothermal elastohydrodynamic lubrication (EHL) problem of skew roller pairswas investigated mainly on the theory and experiment in this thesis. Four problemswere included, i.e., analysis of the lubricating performance of roller pairs under wavesupplied oil conditions; EHL analysis between a skew roller and infinite plane; a studyof lubricating mechanism of skew roller based on roller bearings; and the design andmanufacture for an oil film measurement test rig of roller pairs and a study onexperimental results.First of all, based on the actual oil-supply conditions, a special oil-supply function isproposed. The special oil starvation phenomenon of roller pairs is qualitativelysimulated. And a numerical algorithm of starved EHL was learned as the base forfurther study. A complete numerical solution for the EHL roller pairs has been obtained.It was found that, the lubrication performance of the contact area is not only dominatedby the quantity of the supplied oil, but also be influenced by the wavelength and theamplitude of wave supplied oil model.Secondly, as for a contact pari model formed by a roller and an infinite plane,isothermal steady-state EHL problem of the roller pairs is studied under the conditionsof skew roller. Variations in the entrainment speed, the load and the end profilemodification are discussed under the skew roller condition. Analysis shows that, theroller skew will reduce the lubricating performance of the contact area. Howevercompared with that of tilt roller, the harm of roller skew is weaker.Then, based on the actual cylindrical roller bearing, the EHL mathematical modelbetween a roller and races is established, and a full numerical EHL solution is obtainedunder roller skew condition. The influence of the roller skew angle on the lubricationstatus of contact pairs is analyzed. And the influences of different ring radius, speeds, loads and lengths of roller are investigated under the roller skew condition. The rollerprofile modification is adopted to reduce the harm of skew roller.Finally, in order to achieve the special measurement needs for the tilt or skew rollercondition in EHL, a test rig is designed and manufactured, and a special adjustmentdevice is used to achieve the EHL film measurement under tilt or skew roller condition.At the same time, the experimental results of different roller skew angles, entrainmentspeeds and loads are analyzed. Compared with the theoretical results qualitatively, thevariation tendency is consistent.