Far-field noise prediction for different geometries with Hybrid method

In this study, to investigating the efficiency of the Curle and the compact form of the acoustic analogy in the far-field noise prediction, the flow around a square, a circular and an elliptic cross-sectional geometry at Reynolds numbers of 46000 and 69000 are simulated in the open-source software, OpenFOAM. The large eddy simulation approach has been used to simulate the incompressible flow around the geometries. To predict the far-field sound pressure levels with the Curle acoustic analogy, the data of the surface pressure fluctuations has been used, which were saved during the simulations through the probe utility of OpenFOAM, while with the compact form of the Curle acoustic analogy, the fluctuations of the lift coefficient have been used. To validate the numerical approach in the study, in the first part of the results, the average aerodynamic coefficients (lift, drag coefficients), mean pressure coefficient, Strouhal number and the formation of the coherent structures of the flow through Q-criterion are investigated.In the second part of the results of the present study, the far-field sound pressure level due to the interaction of the flow with the geometries were investigated. To validate the results in this section, the far-field sound pressure level of the geometry with square cross-section has been investigated and the proper precision of the approach has been evaluated. Finally, the results of the study have shown that the geometry with the square cross-section produces the maximum and the geometry with the elliptical cross-section produces the minimum far-field sound pressure level.