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Advances in Aircraft and Spacecraft Science Volume 7, Number 5, September 2020 , pages 387-404 DOI: https://doi.org/10.12989/aas.2020.7.5.387 |
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A hybrid numerical flux for supersonic flows with application to rocket nozzles |
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Andrea Ferrero and Domenic D\'Ambrosio
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| Abstract | ||
| The numerical simulation of shock waves in supersonic flows is challenging because of several instabilities which can affect the solution. Among them, the carbuncle phenomenon can introduce nonphysical perturbations in captured shock waves. In the present work, a hybrid numerical flux is proposed for the evaluation of the convective fluxes that avoids carbuncle and keeps high-accuracy on shocks and boundary layers. In particular, the proposed flux is a combination between an upwind approximate Riemann problem solver and the Local Lax-Friedrichs scheme. A simple strategy to mix the two uxes is proposed and tested in the framework of a discontinuous Galerkin discretisation. The approach is investigated on the subsonic flow in a channel, on the supersonic flow around a cylinder, on the supersonic flow on a flat plate and on the flow in a overexpanded rocket nozzle. | ||
| Key Words | ||
| hybrid flux; carbuncle; shock capturing; supersonic flow; discontinuous Galerkin | ||
| Address | ||
| Andrea Ferrero and Domenic D\'Ambrosio: DIMEAS, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy | ||
