Efficient Optimization Based on FEA and CFD Simulations

Bead optimization of a muffler to increase frequencies

Customer Request

The dynamic behavior of a muffler of an automotive fuel gas system had to be improved. Thus, bead stiffeners had to be implemented to increase the first and second eigenfrequency of the exhaust muffler. To ensure the part's production, manufacturing restrictions had to be considered.

Our solution: shape optimization with Tosca Structure

The selection of the correct bead pattern is often very difficult as many load cases have to be considered. Optimization with Tosca Structure.bead automatically generated a bead layout based upon the results from finite element analysis. The resulting bead pattern maximized the first eigenfrequency with a maximum bead height of 5mm. Manufacturing restrictions were formulated as constraints for the optimization task.

Benefit for the customer

Using Tosca Structure.bead the desired structure could be derived in a very short time and saved time-consuming trial-and-error processes. All restrictions were directly included in the layout process which prevented subsequent rework. After only three FE-Analyses TOSCA Structure.bead automatically generated an optimum bead layout and verified the modifications. The frequencies of interest could be increased from 280 Hz to 520 Hz (first natural frequency) and from 340 to 570 Hz (second natural frequency). Thus a significant improvement of the acoustic and dynamic behavior (in particular the noise disturbance) could be achieved.