NUMERICAL SIMULATION OF THE INVISCID FLOW PAST AIRFOILS

Khalid M.  Sultan; Basim A. Belgasim

doi:10.66411/jer.v9i9.162

Authors

Khalid M. Sultan Mechanical Engineering Department, Faculty of Engineering, Garyounis University, Benghazi, Libya Author
Basim A. Belgasim Mechanical Engineering Department, Faculty of Engineering, Garyounis University, Benghazi, Libya Author

DOI:

https://doi.org/10.66411/jer.v9i9.162

Keywords:

Unstructured Cartesian grid, Euler equations, AUSM scheme

Abstract

For many engineers and researchers, the simulation of the flow field around aerodynamic shapes such as airfoils or turbine and compressor vanes is of particular interest. In these situations, the computations are almost carried out using commercial softwares that are available in the market. Nevertheless, these softwares are always provided without the source code, and hence they leave no chance for the user to modify and develop their existing algorithm. In this study, an unstructured Cartesian grid generator and flow solver was built from scratch in order to simulate inviscid flows past airfoils. In the grid generator, the ray-casting method is employed to classify the cells in the computational field to flow, body, or cut cells. In order to find the coordinates of the cut cells the surface of the given shape is represented by a set of consecutive Bezier curves. The governing equations are discretized using the AUSM scheme for the convective terms and a five-stage Runge-Kutta method for the unsteady terms. The grid generator based on the ray-casting method and Bezier curves showed good performance in representing the given geometries despite the simplicity of the method. The flow solver that is based on the AUSM scheme and Runge-Kutta method showed very good agreement when compared with the available literature. Work is now in progress to incorporate some adaptation sensors to enable the solver to adapt the grid during the solution process

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