Unsteady Flow Distortion Past Blades: Source of Noise Generation in Rotating Flows.

Abstract

The overall goals of this program are to: (1) Determine the instantaneous flow structure past blading and interpret it in terms of pressure sources using high-image-density particle image velocimetry. In turn, these pressure source terms are to be decomposed into vorticity-related and rate-of-strain related contributions; (2) Establish active (open loop) control concepts for flow past blading. Generic leading-and trailing-edge interactions will be addressed. Control concepts are to incorporate harmonic, amplitude- and frequency-modulated disturbances. Attempts will be made to: (a) Destabilize normally coherent fluctuations into multiple-spectral or broadband distributions; (b) Restabilize modulated fluctuations to a periodic state; and (c) Modify the level of broadband fluctuations; (3) Implement active control concepts in a unique, actively-controlled radial flow machine, allowing arbitrary inflow and impeller perturbations. The flow structure in the machine is to be subjected to various phase-shifting concepts in order to optimize the flow control; and (4) Develop new approaches to high-density particle image velocimetry, involving innovative approaches to acquisition of images, as well as processing and post- processing of images to provide global, instantaneous insight. (KAR) p. 2

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Document Details

Document Type
Technical Report
Publication Date
Jul 02, 1993
Accession Number
ADA298903

Entities

People

  • Donald O. Rockwell

Organizations

  • Lehigh University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Applied Mechanics
  • Boundary Layer
  • Broadband
  • Computational Fluid Dynamics
  • Engineering
  • Flow
  • Flow Separation
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Mechanics
  • Frequency
  • Mechanics
  • Particle Image Velocimetry
  • Radial Flow
  • Three Dimensional
  • Trailing Edges
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Fluid Mechanics and Fluid Dynamics.
  • Robotics and Automation.