RESEARCH IN PROGRESS DURING CALENDAR YEAR 1961 UNDER THE AUSPICES OF THE U. S. ARMY RESEARCH OFFICE (DURHAM)
Abstract
A theoretical study reported herein was made to investigate the aeroelastic characteristics of a jet-flap rotor system in hovering flight. The jet-flap rotor system considered was a two-blade symmetrical rotor having a teetering hinge on the axis of rotation and flapping hinges beneath the teetering hinge which were symmetrically offset from the axis of rotation. The following general conclusions were drawn regarding the dynamic and aeroelastic characteristics, over the normal range of operating conditions and parameter values: (1) The aeroelastic stability is insensitive to changes in the elastic-axis position or to changes in the nonrotating torsional-tobending frequency ratio. (2) For a rotor having no teetering degree of freedom, the effects on the rotor stability of increased jet-blowing and aft movement of the center of gravity are similar and are destabilizing. (3) The dynamic characteristics of the jet-flap control may strongly influence the stability characteristics of a jetflap rotor system. (4) Vertical offset of the flapping hinges of a doubly articulated rotor can have a very destabilizing influence. (5) Horizontal offset of the flapping hinges does ot affect the stability characteristics of the rotor system. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1961
- Accession Number
- AD0275101
Entities
Organizations
- Army Research Office