Bo Jacobson

Elastohydrodynamic Lubrication of Line Contacts

A procedure for the numerical solution of the complete isothermal elastohydrodynamic lubrication problem for line contacts is outlined. This procedure calls for the simultaneous solution of the elasticity and Reynolds equations. In the elasticity analysis, the conjunction is divided into equal rectangular areas. It is assumed that a uniform pressure is applied over each area. In the numerical analysis of the Reynolds equation, the parameter π = QH3/2 is introduced in order to help the relaxation process. The analysis couples the elasticity and Reynolds equations, going from the inlet to the outlet without making any assumptions other than neglecting side leakage. By using the procedures outlined in the analysis, the influence of the dimensionless speed U, load W, and materials G parameters on minimum film thickness is investigated. Ten cases are used to generate the minimum-film-thickness relationship, ℏmin = 3.07 U0.71G0.57W−0.11. As was first discovered by Dowson and Higginson, the most dominant exponen...

Measurement of the Density of Base Fluids at Pressures to 2.20 GPa

The influence of pressure on the density of six base fluids is experimentally studied for a range of pressures from 0.422 to 2.20 GPa. An important parameter used to describe the results is the cha ...