Isothermal Flowfield Predictions of Confined Coflowing Turbulent Jets in an Axisymmetric Bluff-Body Near Wake.

Abstract

Numerical computations are carried out to predict the turbulent flowfields under isothermal conditions in the Aero Propulsion Laboratory (APL) combustor. This combustor consists of an axially symmetrical configuration with a cylindrical bluff body placed inside a duct. Turbulent convection, diffusion and mixing of two coaxial jets - one flowing in the annulus between the duct and the bluff body and the other flowing through a central tube in the bluff body - occur in the near-wake region of the bluff body. The ongoing APL experimental program involves both nonreacting and reacting situations, with air in the annular jet and with CO2 or air or propane (for combusting flows) in the central jet. The isothermal modeling predictions reported herein consider the influence of the annular and central flow rates and of the central-jet fluid on the nature of the flowfield downstream of the bluff body. The numerical computations are performed with the Field Relaxation Elliptic Procedure (FREP) Code. A constant effective eddy viscosity is employed in the calculations. The numerical results have demonstrated the complex nature of the flowfield interactions in the near-wake region under different flow rates in the annular and central jets. The character of the flowfield emerging from the numerical predictions when the near wake is dominated by the annular jet or the central jet is in conformity with the APL experimental observations and with the heuristic description suggested therefrom.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
May 01, 1981
Accession Number
ADA103639

Entities

People

  • L. Krishnamurthy

Organizations

  • University of Dayton

Tags

Communities of Interest

  • Air Platforms
  • Cyber

DTIC Thesaurus Topics

  • Aeronautical Laboratories
  • Air Flow
  • Combustion
  • Combustors
  • Computational Fluid Dynamics
  • Convection
  • Differential Equations
  • Diffusion
  • Flow
  • Fluid Dynamics
  • Fluid Mechanics
  • Hydrodynamics
  • Payload
  • Predictive Modeling
  • Radial Velocity
  • Stagnation Point
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Combustion science or combustion engineering.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)