Aeroacoustic Modelling Module Added to Customised OpenFoam®

TotalSim are currently testing a new aeroacoustic module added to their customised version of OpenFoam®**. This work has been funded by an existing Support Customer who has kindly agreed to allow this code to be used in TotalSim’s general release.

openfoam-acoustic-analogy-module-mirror-flow

This post shows some of the early results we have from testing this code on a fairly standard isolated mirror test case which we found reasonable experimental data for. Despite this just being a fairly small model, the code has actually been developed for use on production level detail road cars.

The core functionality added is an acoustic analogy algorithm based on Curle’s formulation to allow noise levels to be predicted at mid and far field receivers.

acoustic-analogy-curle-formulation

 

 

There are some assumptions with this approach but these are thought to be reasonable for upper body noise generation in automotive problems. Also, the ability to plot sound pressure level (in dB) on the surfaces of a model based on a frequency range has been added.

The image below shows some selected off body results of the acoustic analogy module with the experimental data taken from a 2005 paper from Chalmers University of Technology. Comparison is also made to running the same CFD mesh in the acoustic module of Fluent v14 (with as close a model setup as possible).

This new module is designed for use with TotalSim’s fixed time step DES configuration and is primarily a post-processing tool. As such it is hopefully a fairly painless process to run on an existing DES model.

For further information about this module then please feel free to contact us.

openfoam-acoustic-analogy-module-mirror-results

**OpenFOAM® and OpenCFD® are registered trade marks of ESI.