Abstract (EN):
This article presents an efficient methodology for the calibration and validation of a numerical model of a freight wagon based on a dynamic test under real operation conditions. The dynamic test takes place during a regular journey of the train and involved the installation of on-board accelerometers and LVDTs, whose number and location was conditioned by the space occupied by the goods and constraints associated with loading and unloading the wagon. The data derived from the dynamic test was used for the identification of carbody's modal parameters, namely the frequencies, mode shapes and damping coefficients and to extract accelerations and displacements time-histories. A three-dimensional (3D) FE numerical model of the freight wagon was developed and calibrated using a genetic algorithm. The methodology proves efficiency and robustness in precisely estimating three numerical parameters, besides a significant upgrade in relation to the model before calibration. Model validation involved the comparison between numerically simulated results, based on a vehicle-track dynamic interaction analysis, and the experimental observations. An excellent agreement between experimental and numerical after updating time-histories was obtained, especially for the carbody responses, whose behaviour is governed by lower frequencies (below 3.5 Hz), in which the calibration process was focused.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
27