Kevin Allin, Jaguar Land Rover
This paper details a technique for optimising driveline Computer Aided Engineering (CAE) system models, in order to minimise the response to known excitations, such as final drive unit transmission error and system out-of-balance forcing. The aim of the CAE analysis is to give the design team an understanding of how to desensitise the vehicle to these known excitations, and to enable informed decisions to be made, for example when trading attributes between Noise, Vibration and Harshness (NVH), and driveability, etc.
The approach uses the forced response analysis capability within OptiStruct and the mesh morphing capabilities of HyperMorph to calculate the optimum settings for the various driveline parameters, such as centre bearing position, propshaft tube diameter, and mount stiffness rates. HyperStudy is then used to automatically submit a suite of OptiStruct runs, and subsequently perform a Design of Experiments analysis showing how the various parameters interact.
The results are then combined in a multi-disciplinary optimisation run, to give an overall optimum position that also takes into account separate analysis runs, such as multi-body systems assessment of static displacements.