Calculation of Rotor Performance and Loads Under Stalled Conditions

Abstract

Rotor behavior in stalled conditions is investigated using wind tunnel test data of a 1/10-scale CH-47B/C type rotor, which provides a set of test conditions extending from unstalled to light stall to some deep stall conditions over a wide range of advance ratios. The rotor performance measured in the wind tunnel is similar to the main rotor performance measured during the NASA/Army UH-60A Airloads Program, although the two rotors are quite different. The analysis CAMRAD II has been used to predict the rotor performance and loads. Full-scale airfoil test data are corrected for Reynolds number effects for comparison with the model-scale rotor test. The calculated power coefficient shows good correlation with the measurements below stall with the Reynolds number-corrected airfoil table. Various dynamic stall models are used in the calculations. The Boeing model shows the lift augmentation at low advance ratios and the Leishman-Beddoes model shows better correlation of torsion moment than the other models at mu = 0.2. However, the dynamic stall models, in general, show only a small influence on the rotor power and torsion moment predictions especially at higher advance ratios.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 2003
Accession Number
ADA480697

Entities

People

  • Hyeonsoo Yeo

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Characteristics
  • Coefficients
  • Data Sets
  • Dynamic Pressure
  • Fluid Dynamics
  • Frequency
  • Helicopters
  • Mach Number
  • Measurement
  • Physical Properties
  • Power Measurement
  • Resonant Frequency
  • Reynolds Number
  • Structural Properties
  • Two Dimensional
  • Wind Tunnel Tests
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Aerospace Engineering