Computational fluid dynamics as a means of assessing the influence of aerodynamic forces on the mean contact force acting on a pantograph

Abstract

This paper discusses the possibility of using computational fluid dynamics (CFD) to assess the influence of aerodynamic forces (aerodynamic uplift) on the mean contact force acting between a pantograph and the contact wire. The analysis consists of experimental tests and CFD simulations, performed in both wind tunnel and on-track scenarios. A method for the computation of the aerodynamic uplift and for the assessment of the contact force imbalance between the leading and trailing collectors is proposed. The method is based on the virtual work principle, and exploits both the numerical forces resulting from CFD analysis, and the Jacobian terms obtained from a kinematic analysis of the pantograph. The proposed model takes into account stationary phenomena, and it is fully validated by means of experimental results.