Accuracy assessment of Ro 3rd order and CUSP dissipation schemes to analyze transonic flow around pitching airfoil using structured spring network

Subject Areas : Fluid Mechanic

Ali  Heydari ¹ (استادیار، گروه مهندسی مکانیک، واحد سمنان، دانشگاه آزاد اسلامی ، سمنان، ایران)

Received: 2015-06-18 Accepted : 2015-06-21 Published : 2012-11-21

Keywords: Structured grid network, linear spring, moving adaptive, CUSP dissipation scheme, upwind RO dissipation scheme,

Abstract :

In this article, the unsteady transonic flow analysis with moving boundary is considered to compare dissipation schemes consist of: SCDS scheme, Ro 3rd order and CUSP methods. So that the unsteady, two-dimensional, non-viscous, compressible flow around an oscillating airfoil is investigated by solving Euler equations with adaptive grid network. To enhance the ability of moving grid network and prevent interference grids, linear springs are used in tangential and normal direction to the surface. Also the difference between the upwind (Ro) and the central difference CUSP dissipation scheme analysis is studied. The main problem, which occurs to the solution of equations as a result of the phenomenon of shock in central differences, is instability and non-continuity in the solution because of the lack of shock information. To solve the problem the artificial dissipation is used. In this way, the oscillating airfoil motion, the adaptive network and artificial dissipation are modeled. For validation, results are compared with experimental data. Finally, the numerical accuracy is checked. The results show that the of solving the CUSP scheme at the airfoil trailing edge and the shock capturing leads to better accuracy.