Use of Blade Sweep to Reduce 4/Rev Hub Loads,

Abstract

The effect of blade planform sweep on the 4/rev hub loads for a four-bladed, fully-articulated rotor was analytically investigated. Substantial vibratory hub load reductions could be achieved by using aft tip sweep. However, the mathematical model and the blade definition were too complex to understand the source of the reduction. To aid in understanding the physical mechanism, a model of a simplified blade was defined that still showed substantial hub load reductions. Using this simplified model, an extensive blade parameter sensitivity study was performed. It was determined that those properties which are related to the dynamic torsional response of the blade were important in determining the effectiveness of both aft and forward tip sweep in reducing the 4/rev vertical hub load. An extensive investigation into the source of the hub load reduction was performed, and a number of hypotheses were developed.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1987
Accession Number
ADA182247

Entities

People

  • Darrell K. Young
  • Donald L. Kunz
  • Frank J. Tarzanin

Organizations

  • Boeing Rotorcraft Systems

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Aerodynamic Lift
  • Airspeed
  • Amplitude
  • Blade Tips
  • Blades
  • Center Of Gravity
  • Computer Programs
  • Frequency
  • Gravity
  • Helicopters
  • Mach Number
  • Physical Properties
  • Resonant Frequency
  • Vibration
  • Wind Tunnel Tests
  • Wind Tunnels

Readers

  • Aerodynamics.