Flow-induced oscillation in rectangular cavities is a captivating phenomenon in fluid dynamics with implications for many engineering applications. The oscillations can cause increased drag, noise, and structural vibrations, making their study crucial for fields like aerospace engineering. Understanding and controlling these oscillations is essential for optimizing designs across different applications. Hopefully, a thorough study was conducted on the same topic in a paper entitled “ Numerical Identification of Flow-Induced Oscillation Modes in Rectangular Cavities using URANS”, which is our reference paper in this exploration.

Figure 1: Reference Paper`s designed computation domain

Simulation Process

The set of governing equations is numerically solved in the computational domain shown in Fig. 1. The cavity has a length to depth ratio (L/D) of 4, and simulations are performed. It is then converted into cells using ANSYS Meshing, regarding a denser grid near the walls. Overall, 290500 cells establish the structured grid. As mentioned above, the application in the aerospace industry leads to assuming high Mach number flow. Further, the Transition SST 4 equation turbulence model is utilized.

Figure 2: the produced Structured grid with denser cells near the critical regions

Post-processing

The results from simulating flow-induced oscillation in a rectangular cavity uncover fascinating fluid dynamics phenomena. The velocity contour plot displays a unique flow pattern with a distinct vortex formation within the cavity. The primary flow, denoted by the red area, demonstrates high velocity above the cavity opening. When this flow reaches the cavity, it generates a shear layer at the interface, causing flow separation and the creation of a recirculation zone within the cavity. This is illustrated by the blue area within the cavity, indicating lower velocities and the presence of a vortex. Vortex formation is a critical feature of cavity flows and significantly contributes to the self-sustained oscillations typically observed in such geometries. The interaction between the main flow and the cavity vortex likely leads to pressure fluctuations and potential acoustic resonances. This simulation offers valuable insights into the intricate flow patterns and mechanisms involved in flow-induced oscillations in rectangular cavities, with significant implications for various engineering applications such as aeroacoustics and structural design.