The authors have produced a compelling argument to explain EHL dimple formation as resulting from a temperature-viscosity effect. I believe that their explanation is correct. They have solved the EHL problem for film thickness and traction and compared these with measurements. Any claims of providing quantitatively correct comparisons between experiment and numerical solutions are, however, tainted by the fact that the authors have misrepresented the viscosity of their lubricant in spite of having obtained viscosity measurements.
The authors obtained measurements of the viscosity of the subject liquid, a bright stock called BS, from two laboratories. This laboratory provided viscosity at 23, 60, and 100°C and pressures to 1.16 GPa. Professor Ohno at Saga University provided data at 21 and 40°C and pressures to 0.25 GPa. These measurements for temperatures close to the experimental temperature are plotted in Fig. 1 as the data points. We also provided the non-linear response of...
