ELASTOHYDRODYNAMIC LUBRICATON SOLUTION FOR PARALLEL SURFACES SUBJECTED TO HIGH ACCELERATION

Abstract

Frictional wear is one of the most common causes of material failure. Different studies have been carried out to overcome this type of failure. The different techniques applied in this regard include: smoothening of surfaces to minimize area of contact, coating with special material and many others. Among these, one of the most common techniques is to lubricate the surfaces in contact using an optimum amount of appropriate lubricant. Same technique is utilized in the present case to overcome the problem of frictional wear between two parallel surfaces subjected to high temperature and pressure. The lubrication solution proposed is a modification of “Numerical model for mixed lubrication” presented in 1990s. The objective of present research is to verify the applicability of the model for piston-liner assembly in mixed lubrication developed by Dong Zhu, to the present case of Elastohydrodynamic lubrication for parallel conformal surfaces. Keeping in view the problem constraints as explained in section 3, certain modifications are proposed. Outcome of the research is a graphical pattern showing the lubricant film thickness required at different positions between the contacting surfaces which can overcome the problem of frictional wear. Different grades of Krytox are used for the solution as it is nonflammable, anticorrosive Perfluoropolyether based grease, commonly used for high temperature cases. The results obtained by the numerical model are compared and found well-in-accordance with the experimental data available and with the analytical predictions made by scholars in the past, which verifies the applicability of the model chosen for solution.