A method to numerically assess rail vehicle rolling resistance on tangent and curved tracks

Rail vehicle resistance is a key factor for train energy, driving and planning issues. Direct use of traditional empirical formulas in this regard has been reported as inaccurate for a long time. Field measurements represent a good method to assess vehicle resistance in specific cases; however, they are too costly and often impractical to be carried out. This paper presents a numerical method to assess non-air-drag parts of resistance, including rolling resistance and curving resistance. The method is based on multibody dynamics simulations and frictional/vibrational energy calculations whose results can then be converted into equivalent resistance forces. Five Australian freight wagons are taken as examples. The results show that simulated resistances were lower than empirical values but are sufficiently close for engineering comparisons and sensitivity studies. Resistance differences between empty and loaded wagons were smaller than expected. Curving resistance results are more complex than empirical models suggest.