Model Calibration of a Railway Vehicle

With the help of optiSlang, calibration of a numerical model of an Alfa Pendular train, including the car body, bogies and passenger-seat system, was conducted based on the natural frequencies and modal configurations estimated from dynamic tests.

Model Calibration of a Railway Vehicle
Picture: © Nuno Morão (Wikimedia Commons)

The calibration of the numerical model was conducted with optiSLang through an iterative methodology based on an optimization algorithm and was performed using a multistep approach involving two phases: the first phase focused on the calibration of the model of the bogie under test conditions and the second focused on the calibration of the complete model of the vehicle. A global sensitivity analysis allowed the identification of numerical parameters to be considered in the calibration. The parameters that have shown the highest sensitivities in relation to the modal responses were, for the bogie, the vertical stiffness of the secondary suspension block and the vertical stiffness of the primary suspensions. As for the car body, the RMI parameters of the base and side walls and the vertical stiffness of the secondary suspension were the parameters with highest sensitivity in relation to the modal responses.

Model Calibration of a Railway Vehicle
Numerical model of the BBN vehicle

The optimization was conducted with optiSLang using a genetic algorithm involving a total of 17 numerical parameters and 26 modal responses. The results of the optimization cases of the bogie and vehicle, based on different initial populations, led mostly to very stable numerical parameters’ values, particularly for those highly correlated with the responses. The comparison between the numerical vibration frequencies’ values, before and after calibration, and the experimental vibration frequencies, has revealed significant improvements on the initial numerical models.

Model Calibration of a Railway Vehicle
Numerical rigid body and structural modes of vibration of the carbody

The calibrated numerical model of the vehicle will be used to access the dynamic behaviour of the train-track coupled system, in terms of passengers comfort and wheel–rail contact stability, on plain track, on bridges or on transition zones.

read more (PDF 1.65 MB)

Dynardo GmbH

Employees
50
CAE-Engineers
35
Countries
2
Locations
2
Founded
2001