Numerical Analysis of Supersonic Flows in UCS Using Motionless Viewing Window Technique

Authors

1 M. Sc., Engineering Department, Islamic Azad University, East Tehran Branch, Tehran, Iran

2 Associate Professor, Aerospace Engineering Department, K. N. Toosi University of Technology, Tehran, Iran

Abstract

A fundamental topic in computational fluid dynamics is the role of coordinate particularly for searching optimized coordinates. The objective of this study is the numerical modeling of supersonic flows using a new coordinate system i.e. Unified Coordinate System (UCS) uses moving mesh with motionless viewing window technique. UCS has an advantage over traditional coordinate systems (Eulerian and Lagrangian) in supersonic flows especially in discontinuous regions (shocks and expansions). Moreover most of the difficulties of the traditional coordinate system may be removed by using UCS. Unified coordinate system benefits from both the eulerian and lagrangian systems. This is why a unified coordinate system as an optimization system is introduced. The researchers briefly review how to apply boundary conditions, how to calculate fluxes and strang dimensional splitting. The researchers also explain the Riemann problem which is the basic step to solve the equations in this coordinate and integrated system forms. In this article the researchers use new numerical method that has more advantages than other numerical methods such as slip line and shock resolution and low numerical dissipation. The important fact is that in using the UCS, there is no need to generate a body-fitted mesh prior to computing flow past a body; the mesh is automatically generated by the flow. These can be seen in the numerical results and comparing with exact solutions and also in quick numerical computations.

Keywords