Experimental study of wake impingement on a horizontal stabalizer

Open Access
Author:
Metkowski, Leonard P
Graduate Program:
Aerospace Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
December 08, 2017
Committee Members:
  • Sven Schmitz, Thesis Advisor
  • Mark David Maughmer, Committee Member
  • Amy Ruth Pritchett, Committee Member
Keywords:
  • Aerodynamics
  • Helicopter
  • Hubs
  • Empennage
  • Experimental
  • Interactional Aerodynamics
  • Helicopter Hub Drag
  • Experimental Design
  • Helicopter Hub Experiments
  • Horizontal Stabilizer
  • Helicopter Stabilizer
  • Experiments on Helicopter Stabilizers
  • Wake Impingement
Abstract:
The design and execution of a full-scale Reynold’s number water tunnel experiment was performed to create a data set used to analyze the effects of wake impingement on a canonical helicopter horizontal stabilizer. The experiment was designed and performed in the Garfield Thomas Water Tunnel, where a 10.5 inch chord stabilizer was placed in the 48-inch diameter test section downstream of a 1/4 scale helicopter hub. Computational design tools, including finite element methods, were used to evaluate structural and aerodynamic properties of the model prior to experimentation. The model was designed to be mounted in the far-field wake, which occurs at an estimated seven hub radii downstream. Lift, drag, pitching moments, and unsteady pressures were measured on the horizontal stabilizer. The hub-wake interaction results were compared to a control test, which was performed without a hub upstream. Steady and unsteady pressure sensors were also used to help evaluate primary frequencies within the wake convecting over the horizontal stabilizer. The temporal analysis yielded a 2/rev, 4/rev, 6/rev, and respective higher harmonics in the far-field wake. Further analysis including proper orthogonal decomposition performed on particle image velocimetry fields yielded similar results.