Calibration and validation of the numerical model of a freight wagon based on dynamic tests under operating conditions

Resumo

This work presents an efficient methodology for the calibration and validation of a freight wagon
numerical model by an iterative methodology based on experimental modal parameters identified in a dynamic
test under real operating conditions. The dynamic tests involved the use of a minimalist on-board monitoring
system, which did not cause any interference in the vehicle's operational logistics. The identification of the
vehicle's dynamic properties was made through the application of operational modal analysis techniques to the
data collected during the vehicle circulation. A 3D numerical model of the freight wagon was developed and
calibrated using an iterative methodology through a genetic algorithm and based on the identified modal
parameters. The applied methodology proved to be effective and robust in estimating three numerical parameters,
besides a significant upgrade in the natural frequencies compared to the model before calibration. Finally, the
dynamic response of the model was validated by means of a direct comparison between numerically simulated
results, based on a vehicle-track interaction analysis, and experimentally collected time history responses.
Comparisons revealed an excellent agreement between the experimental and numerical time series after
calibration, especially for the frequency range covered by the identified modes.