Modelling and analysis of pneumatic railway brake system

Abstract

This paper deals with nonlinear lumped multicapacity models with train pipecapacity and brake cylinder capacity lumped separately to predict pressure rise in pneumatic brake cylinders for steptype pressure input. The first model is a two-capacity system in which all the brake cylinder capacitances and the entire pipe line capacitance are lumped separately. The second model is a multicapacity system in which the train pipe capacitance between the brake cylinders of adjacent wagons is lumped near the brake cylinder capacitance in each wagon. The third model is also of multicapacity type, similar to the second model, but includes the effect of varying brake cylinder capacity in its formulation. The viscous effects are handled in a quasi-steady manner to find the friction factor for the case of isothermal flow. The shooting method has been used to solve this initial value propagation-type problem, consisting of a system of nonlinear ordinary differential equations. The theoretical results have been compared with experimental values.