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Accession Number ADA586719
Title High Order Accuracy Methods for PDEs with Shocks and Uncertainties.
Publication Date Jun 2009
Media Count 7p
Personal Author D. Gottlieb
Abstract The aim of this project is the construction of efficient high fidelity schemes for systems of PDEs that contain shock waves. We advocate here the Discontinuous collocation method, i.e. multi-domain spectral method with stable and conservative penalty interface conditions. In this work, the previously developed methodology is generalized to inhomogeneous grid to simulate the two dimensional supersonic injector-cavity system. Non-physical modes generated at the domain interfaces due to the spatial grid inhomogeneity is minimized using the new weighted multi-domain spectral penalty method. The method yields accurate and stable solutions of the injector-cavity system which agree well with experiments qualitatively. Through the direct numerical simulation of the injector-cavity system using the weighted method, the geometric effect of the cavity wall on the pressure fluctuation is investigated. It is shown that the recessed slanted cavity attenuates pressure fluctuations inside cavity enabling the cavity to act potentially as a stable flameholder for scramjet engine.
Keywords Cavities
Flame holders
Partial differential equations
Shock waves
Supersonic combustion ramjet engine
Uncertainty
Variable pressure
Weighting functions


 
Source Agency Non Paid ADAS
NTIS Subject Category 72B - Algebra, Analysis, Geometry, & Mathematical Logic
81A - Combustion & Ignition
Corporate Author Brown Univ., Providence, RI. Div. of Applied Mathematics.
Document Type Technical report
Title Note Final rept. 1 Feb-30 Nov 2008.
NTIS Issue Number 1405
Contract Number FA9550-08-1-0200

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