Flow and Noise Prediction of Doors-on M219 Cavity through Improved Delayed Detached Eddy Simulations

2019-05-14
Coşkun, Seyfettin
Özyörük, Yusuf
High survivability and low observability requirements of modern fighter airplanes necessitate internal carriage of the stores. During their deployment the doors of internal weapon bays are opened transitionally, forming a cavity and hence a highly unsteady and nonlinear flow coupled with acoustic feedback mechanism. These processes present unsteady vibratory loads on the stores and structures. In the present paper, CFD computations of the doors-on M219 cavity with use of Improved Delayed Detached Eddy Simulation (IDDES) are carried out to predict the turbulent fluctuations and the associated noise. Computationally less expensive Unsteady Reynolds-Averaged NavierStokes (URANS) calculations with kω-SST model are also carried out. Comparisons of the attained overall sound pressure levels at various locations on the cavity ceiling with experimental data show the latter approach usually lacks accuracy with overpredicted values, while the former one predicts the levels quite well.
31st International Conference on Parallel Computational Fluid Dynamics, (14 - 17 Mayıs 2019)

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Citation Formats
S. Coşkun and Y. Özyörük, “Flow and Noise Prediction of Doors-on M219 Cavity through Improved Delayed Detached Eddy Simulations,” presented at the 31st International Conference on Parallel Computational Fluid Dynamics, (14 - 17 Mayıs 2019), Antalya, Türkiye, 2019, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/75603.