Case Studies for Comparing Hybrid and Decomposition-based Methods in Aeroacoustics (vor Ort)
* Presenting author
Abstract:
In aeroacoustic simulations the velocity and pressure fields consist of compressible and incompressible components. Computing both parts numerically in one system is a hard task, because of the different scales in the fields. Using acoustical analogies, this problem can be solved, but in this case the feedback of the acoustical part onto the flow is not taken into account.In the hybrid aeroacoustic workflow, an incompressible simulation is done first. Then acoustic sources can be calculated for the purely acoustical simulation. The final outcome is the sound pressure, computed from the latter system. Alternative solutions based on decomposition techniques were also proposed recently. In this case, compressible flow simulations are performed and the acoustic field results from the decomposition. An advantage of this strategy is that back and forth coupling can be taken into account as well. In the paper the above-mentioned methods are compared, by analyzing both workflows in different configurations. Examples will be also shown (rotating vortex pair, cylinder in a crossflow, edge tone), where the differences of the resulting sound fields can be investigated. At the end, the result of the analysis will be discussed.
