Simulation Driven NVH Design

Reducing time to market requires that the time spent analyzing and optimizing designs for NVH characteristics must be shortened.  This is accomplished in two ways; shorter computational time and faster processes.  A very fast eigenvalue solver (AMSES) is used to reduce the calculation time of thousands of modes for models of millions of degrees of freedom.  Besides the solution of the Eigen problem, AMSES also reduces the mass, stiffness, structural damping, and load vectors into the modal space, as well as calculating residual vectors for increased solution accuracy.  Now that we can quickly calculate thousands of modes, the solution of the modal frequency response problem can take significant time if there are many loading frequencies.  The fast frequency response solver, FASTFR, reduces this time from hours to minutes.  On the process side, it typically takes two analyses to get detailed NVH results for frequencies where there are peak responses; one analysis to determine the peak frequencies and one analysis to get the detailed results.  The Altair OptiStruct PEAKOUT capability allows the engineer to get detailed results at peak responses in a single run.  To get Transfer Path results typically requires two runs and one to three intermediate steps to organize the data.  We have implemented an easy to use single run Transfer Path Analysis that reduces a two day process to a single day.  Finally, instead of just analyzing the design, Altair OptiStruct allows you to quickly improve the design with advanced optimization capabilities.


The Author

Harold Thomas