Numerical Modeling and Combustion Studies of Scram Jet Simulation

Abstract

Physical and numerical modeling of turbulent mixing and turbulent combustion in a Scram jet combustion chamber is studied. A high-order finite volume scheme is applied to the flow, accompanied with dynamic subgrid-scale model and local averaging procedure to account for the effect of unresolved small length scales turbulent fluid behavior. The Arrhenius law kinetic mechanism is applied to describe the nonlinearity of chemical reactions. To model combustion, the finite rate chemistry is developed to characterize the combustion process inside the combustion chamber. Results are compared among the finite rate model, the flamelet model/progress variable approach adopted by Stanford PSAAP center and experimental data. Since the mesh requirement to resolve the flame front is too strictfor most combustion simulation applications, the thickened flame model that artificially expands the flame front is investigated. The effectiveness of the model is studied in a one-dimensional context and applied to the three-dimensional Scram jet simulation. The feasible level of thickening factor is determined to make sure that the major flame features should be preserved. The model is further extended to dynamic thickened flame to account for the coexistence of premixed and diffusion flame in the combustion chamber. In another direction, it is extended to reduced chemical mechanism to cut down the time complexity needed to solve chemistry.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2014
Accession Number
AD1024479

Entities

People

  • Ying Xu

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Applied Mathematics
  • Boundary Layer
  • Chemical Reaction Properties
  • Chemical Reactions
  • Chemistry
  • Combustion
  • Combustion Chambers
  • Combustors
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Equations Of State
  • Fluid Dynamics
  • Fluid Flow
  • Heat Transfer
  • Hydrodynamics
  • Ignition Lag
  • Large Eddy Simulation
  • Mechanical Properties
  • Navier Stokes Equations
  • Numerical Analysis
  • Physics Laboratories
  • Reynolds Number
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Computational Fluid Dynamics (CFD)