Fluid Mechanics of Compressible Dynamic Stall Control Using Dynamically Deforming Airfoils

Abstract

This report summarizes the key results from the two components of the study: (1) development of the knowledge and understanding of the fundamental fluid mechanics of the interactions of the unsteady flow occurring under the influence of the time scales of airfoil reduced frequency and dynamic leading edge adaptation at different flow conditions; (2) understanding of the role of the surface flow in compressible dynamic stall onset. For the former, a systematic investigation of the dynamic stall flow (or lack thereof) was carried out using a dynamically deforming leading edge airfoil, which allowed us to establish the fact there are some airfoil leading edge geometries that are indeed dynamic stall free. This offers the hope that rotor blade geometries can be adapted to avoid the destructive dynamic stall effects, while retaining its benefits. In the latter, 148 surface shear stress sensors were installed on an NACA 0012 airfoil and the flow behavior studied for various flow conditions, which showed the various stall onset mechanisms discovered earlier and also that the surface behavior becomes singular prior to stall onset.

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Document Details

Document Type
Technical Report
Publication Date
Dec 04, 2001
Accession Number
ADA398327

Entities

People

  • Muguru S. Chandrasekhara

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Air Platforms
  • Human Systems

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Flow
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Frequency
  • Geometry
  • Hydrodynamics
  • Hypervelocity Flow
  • Leading Edges
  • Mechanics
  • Pressure Distribution
  • Steady Flow
  • Turbulent Mixing
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Distributed Systems and Data Platform Development
  • Fluid Mechanics and Fluid Dynamics.