A Computational Study of Flow Within Cavities with Complex Geometric Features

Abstract

This work examines simulation requirements for ensuring accurate predictions of compressible cavity flows. Lessons learned from this study will be used in the future to study the effects of complex geometric features, representative of those found on real weapons bays, on compressible flow past open cavities. A hybrid RANS/LES simulation method is applied to a rectangular cavity with length-to-depth ratio of 7, in order to first validate the model for this class of flows. Detailed studies of mesh resolution, absorbing boundary condition formulation, and boundary zone extent are included and guidelines are developed for ensuring accurate prediction of cavity pressure fluctuations.

Parallel aeroacoustic computation of unsteady transonic weapon bay using detached‐eddy simulation via open computational fluid dynamics source codes

“…The eddies (4) in the shear layer travel along the length of the cavity and impinge with the rear wall (5). The impinging of the shear layer on the rear wall which is known as the main acoustic source 11 generates vortex circulation zones (6) and acoustic waves which advance upwards (8). The vortex circulation zones advancing towards the anterior wall (7) interact with the shear layer and affect the separation period of the boundary layer from the surface.…”

“…The one-equation transport equation for the turbulent viscosity of Spalart-Allmaras, the other RANS model used for the DES model, is given in (6).…”

“…5 The effects of absorbing boundary condition and mesh resolution on the flow field were investigated in detail for both subsonic and supersonic conditions in the numerical study. 6 Detailed numerical simulations conducted by Babu et al, 7 the effects of the position of the ammunition inside the weapon bay, whether the fins on the ammunition are flexible or rigid, and the fluid-structure interaction (FSI) effects on the fins on the flow field inside the cavity were analyzed. In the weapon bay modeling carried out by Loupy et al, 8 the operation of the doors was performed both statically and dynamically.…”

Angle of Attack Effects on the Induced Structural Loads of a Weapons Bay

“…Nevertheless, the aero-acoustic response of a weapons bay can strongly differ from the standard rectangular cavity. Typical weapons bay aerodynamic and acoustic response is strongly influenced by external factors, such as local design solutions, which alter the reference rectangular shape ( [5][6][7][8][9][10][11][12]). Dedicated studies have shown the strong influence of bay doors on the cavity.…”

Zamana Bağli Sikiştirilamaz Kavi̇te Akişinin Aeroakusti̇k Anali̇zi̇

“…Ön duvardan kavite içine doğru kopan Vorteks Yapıları (4) zaman bağlı karakterlerini korumalarının yanında, kopan bu yapıların Kavite Arka Duvarı ile Etkileşimi (5)kavite içinde Girdap Sirkülasyon Bölgelerini (6) oluşturmaktadır. Ön duvardan kopan vorteks ve girdap sirkülasyonun beslediği Zamana Bağlı Basınç Değişimi (7) Akustik Basınç Yayılımını (8) doğurmaktadır [3]. Akustik yayılım, arka duvardan ön duvara doğru takip ettiği yörüngesinde ön duvardan kopan vorteks yapılarını, akış alanındaki zamana bağlı değişimlere ek olarak etkilemekte ve vorteksin kopma sıklığını değiştirmektedir [1].…”