Damper modelling and its implementation in railway simulation program

This chapter presents a mathematical model of a railway hydraulic damper. The objective is to develop a model suitable to be implemented in a railway simulation program. Computational cost should, therefore, be maintained low not to decrease the simulation speed (rate) to unacceptable values.

A model based mainly in physical characteristics (piston section, volume of the chambers, characteristics of the valves, etc.) is developed. In a first part of the chapter, the modelling of each part of the damper is discussed. Afterwards, the model of the complete damper is constructed and finally, model results are compared satisfactorily with experimental tests.

The chapter also includes a discussion on the numerical problems associated with the developed model and a new simplified version is proposed to overcome the majority of the difficulties presented in the original model.