Quote:
Originally Posted by Big Dave
The coefficient of friction for steel wheels to dry steel rails is the same as rubber tires on polished glare ice.
|
According to
Wikipedia, railroad steel wheel on steel rail has a Crr from 0.0002 to 0.0010, compare that to ordinary car tires on concrete between 0.010 and 0.015. During coast down testing, I have found my car tires to be around 0.012.
I have also found quite a bit of good information in Mark's Standard Handbook for Mechanical Engineers, Seventh Edition. I don't have time to post now on that, but I will try to post up the "summary" section which is most relevant.