Re: Kahuku Specifications and Tractive Effort Calculations

A couple factors I don't see unless they are built in to your 'Loss' number is the coefficient of friction between iron tires on the locomotive and the steel rail. The second missing item is the torque arm delta between the radius of the crank pin and the radius of the tire. For the most part the real tractive effort is the result of the weight of the locomotive on the rail, the force put on the driver tire by the cylinder through the drive mechanism, and the coefficient of friction between the tire and the rail. And this ignores any frictional resistance of all the moving parts. No, I don't have a formulae but this is how I logic the question after 45 + years doing mechanical design.