Motor Oil Dynamic Viscostity Data

[Sefrick]

Good day, I'm seeking dynamic viscosity data for SAE 10, 20, 30 and 40 grade oils at various temperatures, preferably between 15C and 40C.

I need fluids with known viscosities from 50-350 cP that are cheap for a reseach project that I'm doing. I have reasonable data for the above grades @ 40C that ranges from 40-130 cP.

I was hoping I could be pointed in the right direction.

 

[25362]

The ASTM standard viscosity-temperature charts (D 341) enable you to connect two kinematic viscosities (cSt) with a straight line, for example, those at 40^oC and those at 100^oC by knowing the oils viscosity indices [VI]. Base oils may have different VI values than formulated motor oils.

In order to use the chart, convert from cP to cSt by dividing the cP by their densities at the reference temperature. To convert back to cP, do the opposite.

 

[drwebb]

You can extrapolate viscosities of fluids at different temperatures pretty accurately from the Walther equation wich gives a plot of log T (in K) vs. Log(log vis).

 

[jmw]

The spreadsheets at

http://www.viscoanalyser.com/page8.html

will allow you to find density and kinematic viscosity at a range of temperatures.
The ASTM D341 equation used for viscosity spreadsheet is based on the Walther Equation but this uses the kinematic viscosity so you will need to find the density at the various temperatures to convert between dynamic and kinematic viscosity, this is the other spreadsheet on that page.

JMW

http://www.ViscoAnalyser.com