Topic: 76th NIA CFD Seminar: High-Order Discontinuous-Galerkin Schemes using Hyperbolic First-Order System Approach; same DoF as conventional but more accurate
Date: Wednesday, May 18, 2016
Time: 11:00am – 12:00pm (EST)
Room: NIA, Room 137
Speaker: Alireza Mazaheri
Abstract: We propose arbitrary high-order discontinuous Galerkin (DG) schemes that are designed based on a first-order hyperbolic advection-diffusion formulation of the target governing equations. We present, in detail, the efficient construction of the proposed high-order schemes (called DG-H), and show that these schemes have the same number of global degrees-of-freedom as comparable conventional high-order DG schemes, produce the same or high order accuracy solutions and solution gradients, are exact polynomial functions, and do not need a second-derivative diffusion operator. We also present construction of a Weighted Essentially Non-Oscillatory (WENO) limiter for the proposed DG-H schemes. We demonstrate that the constructed high-order schemes give excellent quality solution and solution gradients on irregular triangular elements. Finally, we make some comparisons with conventional DG and interior-penalty schemes.
Bio: Dr. Alireza Mazaheri is a Computational Aerothermodynamicist at NASA Langley Research Center since 2006. Prior to that he worked at Parsons, Inc. (as a research engineer), was a postdoctoral fellow at Pittsburgh University (2004-2005) and a National Research Council (NRC) postdoctoral fellow at the US Department of Energy (2003-2004). He earned his PhD from Clarkson University in Mechanical Engineering, MS from Shiraz University in Computational Thermo-Fluid Engineering, and BS from Guilan University in Fluid Mechanics. Alireza has been involved in several NASA programs/projects, including the Space Shuttle, Orion Multipurpose Crew Vehicle (MPCV), Dream Chaser, Hypersonic Inflatable Aerodynamic Decelerator (HIAD), High Energy Atmospheric Reentry Test (HEART), etc. His current research interests are on development of high-order methods that are capable of producing accurate and noise-free solution gradients (e.g., velocity gradients, heat flux, shear stresses, etc.) on irregular tetrahedral elements.
Additional information, including the webcast link, can be found at the NIA CFD Seminar website: http://www.hiroakinishikawa.com/niacfds/index.html