High Pressure Rheology of Lubricants (Part 5)

The Walther equation is often used for the viscosity temperature characteristics of lubricants. However, it was found that cannot be applied to high pressure viscosity. In this study, relationship between viscosity, and analyzed. As a result, at each negatively proportional square temperature, linear equations converges absolute zero were derived. parallel, thought experiment conducted on ideal liquid. It (ηt=0) liquid constant regardless pressure. This consistent with convergence point in above analysis. Furthermore, incorporating eqaution van der Waals type consisting three intrinsic constants: ηt=0 [mPa·s], 1/B [GPa/K2] C/B [GPa]. equation. also equivalent PR [GPa] state By this, lubricant can estimated from derived