Numerical analysis of hammershock phenomena in RAE-M2129 S-shaped air intake

This study focuses on establishing a comprehensive framework for numerically analyzing air intakes in defense applications. Responding to the shift towards open-source software in the defense sector, it was proposed using open-source tools to study aerothermal and fluid-structural interactions in air intakes. Guided by extensive literature, the validated RAE M2129 air intake geometry was selected for investigation. OpenFOAM was chosen for its reliability and active community. While open-source mesh tools were not used, employing tools like snappyHexMesh could simplify mesh creation for RAE M2129. While doing steady-state analyses, the rhoSimpleFoam was employed after appropriate pre-processing, mesh preparation and boundary condition specification. Results from various mesh densities were compared against literature benchmarks validating the proposed procedure. Notably, minor deviations in certain parameters were observed, and the results were compared with the literature. Venturing into unsteady simulations utilizing rhoPimpleFoam, fluctuations in the simulation results in comparison of steady-state counterparts were noted. An interesting aspect of this study is the simulation of the hammershock phenomenon. This is achieved by introducing a sudden pressure change at the outlet, a technique crucial for gaining insights into turbulence, flow variations, and fluid-structure interactions during the design of air intakes. Post-processing efforts utilizing Paraview unveiled essential insights into the air flow dynamics, manifesting in velocity contours, mach contours, wall streamlines, and Schlieren-like images of density gradient. The study's implications underscore the necessity of an open-source CFD framework for comprehending air intake aerothermodynamics and fluid structure interactions within the defense industry. The study's contributions extend to the future trajectory of CFD research in air intakes. While the present work focused on a single air intake geometry, prospects abound for broader applications, including complete aircraft bodies. Furthermore, the application of hammershock through varying pressure distribution and the introduction of realistic factors such as compressor-induced suction area will be possible with more computational resources. In conclusion, this study demonstrates the practicality of utilizing open-source software, specifically OpenFOAM, to solve the complex dynamics in air intakes within the defense sector. The adoption of such approaches holds the potential to refine air intake design, strengthen the consistency of airflow, and enhance the effectiveness of applications in the defense industry.