Acoustic near field topology optimization

Here I share my talk I gave on ECCM 2010. It presents acoustic near field optimization. Last year, at WCSMO-8 I compared acoustic topology optimization where the acoustic field was assumed to be far field/ plane wave type/ constant acoustic impedance at the structure itself (so no acoustic is calculated) and at the boundary of by acoustic domain. Now I did the step further and optimize the acoustic power directly w/o any assumption. Thanks to Michael Stingl who helped with some very useful comments! It turned out, that the same objective function had already been used in Jensen and Sigmund; Topology optimization of photonic crystal structures: a high-bandwidth low-loss T-junction waveguide; 2005. It was disappointing that it had (for other physics) already been done - but it would have been really bad if I had not found it and claimed it as a own result.

For my numerical examples the optimal results where quite close to the acoustic far field optimization. This was quite surprising but before I could for lower frequencies not guarantee any physical validity. So it was definitely worth it.

Acoustic near field topology optimization of a piezoelectric loudspeaker