viscosity change 100-150°c

Nov 12, 2021
this is from an older thread by caterham:

"We also know that viscosity change with temperature has lost the parabolic effect that occurs at low temp's and from 100C to 150C and higher, viscosity change with temperature is virtually linear."

could you (or somebody else) expand on the "linear" part? what viscosity are we talking about and are you really saying the change will be proportional or did you mean in relation to the logarithm or ...?

Viscosity vs temperature is a log/linear relationship. When so plotted, the curve is flat (at higher temperatures) and so is referred to as linear, meaning in the plot. It begins to curve at low temperatures, exactly where depends on the chemistry.