Accession Number:

ADA242321

Title:

Loading and Vibration Reduction through Active Aerodynamic Control

Descriptive Note:

Quarterly progress rept. 13 Jun-13 Sep 91,

Corporate Author:

UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT

Personal Author(s):

Report Date:

1991-09-13

Pagination or Media Count:

15.0

Abstract:

The objective of this work is to provide active aerodynamic control concepts for reducing propulsor blade unsteady lift and moments. These unsteady forces are responsible for vibration and noise during an encounter with an incident gust. This effort represents an extension of a recent UTRC breakthrough in which active aerodynamic control was used to reduce noise generated during a two dimensional 2-D blade-gust interaction. The associated reductions in unsteady blade surface pressures responsible for the noise reduction will be evaluated under the current program. Also, an analytical effort will generate a computer code for predicting surface pressures created by an actively controlled flap system and will estimate the required flap motion to cancel the unsteady lift. This work will extend the UTRC 2-D expertise in active aerodynamic control to a three dimensional 3-D capability. This will be done by analytically investigating the effect of a swept gust interacting with an actively controlled, segmented flap to control the bending moment as well as the lift. Also, an exploratory experimental study on the effects of a swept gust encountering a 2-D non-segmented flap will be performed. In summary, this study will provide the Navy with concepts for active aerodynamic control for reducing unsteady blade loads responsible for structural vibration.

Subject Categories:

  • Marine Engineering
  • Fluid Mechanics
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE