H sayyaadi - associate professor
N sholouhi - ph.D student mechanical engineering department

The secondary suspension of most new EMU and DMU rail vehicles is equipped with air springs to serve a good ride comfort to the passengers as the performance of suspension component especially for air spring have significant effects on rail - vehicle dynamics and ride comfort of passengers a complete nonlinear thermo-dynamical air spring model which is a combination of two different models is introduced.

air spring , rail vehicle , thermo-dynamical effects, ride comfort.