Accession Number : AD1024476


Title :   Turbulent Combustion Study of Scramjet Problem


Descriptive Note : Technical Report


Corporate Author : Research Foundation of SUNY at Stony Brook Stony Brook United States


Personal Author(s) : Gong,Xiaoxue


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1024476.pdf


Report Date : 01 Aug 2015


Pagination or Media Count : 158


Abstract : In this thesis we study the turbulent mixing and turbulent combustion in a model scramjet combustor with a Large Eddy Simulation (LES) strategy. LES resolves the large and energetic motions while the small subscale motions are modeled. Here the filtered Navier-Stokes equations are solved by a fifth-order finite difference Weighted-Essentially Non-Oscillatory (WENO) scheme dimension by dimension. The subgrid terms are closed by the dynamic Smagorinsky model. The chemical source terms are calculated directly using a finite rate chemistry model with a reduced chemical mechanism. The turbulent boundary layer model of J. Larsson is used to calculate the shear stress and heat flux at the wall. The inflow turbulent is generated by the digital filtering method. The main result is a methodology to predict the mesh convergence for three-dimensional turbulent combustion simulation, based on a less expensive suite of one-dimensional and two-dimensional simulations. We first determine the grid requirements for finite rate chemistry with detailed mechanism and reduced chemical mechanism respectively in the context of one-dimensional simulations. These criteria are verified through simulation in a two-dimensional context and refined with corrections due to turbulent transport. They are then applied to three-dimensional simulations. A grid sensitivity study of the turbulent boundary layer is conducted in a 2D context. Simulation results are validated through comparison with a simulation of the same problem conducted by J. Larsson, using a different methodology and by comparison to experiments performed at Stanford University.


Descriptors :   supersonic combustion ramjet engines , turbulent mixing , combustion , Turbulent Boundary Layer , Convergence , theses , Conservation Laws (mathematics)


Subject Categories : Fluid Mechanics
      Combustion and Ignition
      Jet and Gas Turbine Engines


Distribution Statement : APPROVED FOR PUBLIC RELEASE