Application of Similarity Laws to a Scaled Railway Bogie Model

摘要

For a dicone moving on a pair of cylindrical rails the equations of motion are established. The friction forces due to Kalker's theory of rolling contact are approximated by non-linear functions. For this non-linear system conditions for the dynamical similarity of a scaled and the full scale model are derived. The equations of motion are extended to a railway car model with two conical wheelsets. Numerical simulation results for the dicone as well as for the bogie model are obtained with a particular software taking into account the structure of the equations of motion in form of differential equations coupled with algebraic equations for the constraints. The simulation results are compared with experiments on a 1:5 scaled roller rig where the railcar model has been designed with the aid of scaling factors for length, mass, inertia and suspension stiffness due to the dynamical similarity laws. The results indicate that the non-linear behavior of designs of railway running gears or even complete vehicles can be investigated in a wide range on a scaled test rig, where the design parameters can be changed more easily than on a full scale test bench.