Performance and Flow Regimes in Plane 2-D Diffusers With Exit Channels at Low Reynolds Numbers

Abstract

A numerical study on laminar incompressible flows in 2-D straight walled diffusers in the low Reynolds number regime (105-1048) is presented to investigate performance and various flow regimes that might exist. Tail channels are situated downstream the diffusers. Geometries with area ratios AR-=1.15 to 5 and non-dimensional lengths of L/W1=1 to 48 are considered. Results are presented in terms of flow regime maps for Reynolds numbers of 105, 210, 314, 420, 629, 1,048 and pressure recovery coefficients maps for Re numbers of 105, 210, 314, 420 and 629. In addition time resolved simulations of impulsively starting flow are considered at Re=210, 314 for 12 geometries on the flow regime map. Four flow regimes can be distinguished depending on diffuser geometry. With increasing divergence angle the flow goes from attached to symmetrically separated to asymmetrically separated and finally to a non 2-D pattern respectively.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2003
Accession Number
ADA418272

Entities

People

  • Epameinondas Trivilos

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Differential Equations
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Geometry
  • Hydrodynamics
  • Incompressible Flow
  • Literature Surveys
  • Mechanical Engineering
  • Pressure Distribution
  • Reynolds Number
  • Steady Flow
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Fluid Mechanics and Fluid Dynamics.