Designing an inset railway switch using a dedicated computational tool

A railway turnout is a complex mechanical system used to divert trains from a particular direction or track. Due to the wheel load transfer from one rail to another, high vehicle-turnout forces occur, leading to rapid degradation of the railway turnout and increasing maintenance costs. Although the optimization of railway turnouts wheel-rail interface designs is highly beneficial, efficient tools capable of automatically creating turnout models for assessing their wheel-rail interaction performance are not the current practice. This work proposes a comprehensive computational study focused on the design of an inset switch rail. A dedicated computational tool was created to generate the switch rail geometry based on the manufacturing operations. This tool requires simple inputs, like profiles and paths of extrusion and cutting Boolean operations, to automatically determine a set of rail profiles that represents the switch design. Large sets of designs are quickly created by changing the paths of some Boolean operations. A total of 320 alternative switch designs were analysed and compared by performance indicators extracted from multibody simulations. Both through and diverge routes and facing and trailing directions were considered. An overall scoring is applied by considering several weighting combinations so that a number of designs can be proposed to best suit certain operating conditions or customer requirements.