NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
The Effect of Laminar Flow on Rotor Hover PerformanceThe topic of laminar flow effects on hover performance is introduced with respect to some historical efforts where laminar flow was either measured or attempted. An analysis method is outlined using combined blade element, momentum method coupled to an airfoil analysis method, which includes the full e(sup N) transition model. The analysis results compared well with the measured hover performance including the measured location of transition on both the upper and lower blade surfaces. The analysis method is then used to understand the upper limits of hover efficiency as a function of disk loading. The impact of laminar flow is higher at low disk loading, but significant improvement in terms of power loading appears possible even up to high disk loading approaching 20 ps f. A optimum planform design equation is derived for cases of zero profile drag and finite drag levels. These results are intended to be a guide for design studies and as a benchmark to compare higher fidelity analysis results. The details of the analysis method are given to enable other researchers to use the same approach for comparison to other approaches.
Document ID
20170005472
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Authors
Overmeyer, Austin D.
(Army Aviation Research and Development Command Hampton, VA, United States)
Martin, Preston B.
(Army Aviation Research and Development Command Hampton, VA, United States)
Date Acquired
June 12, 2017
Publication Date
May 9, 2017
Subject Category
Aerodynamics
Report/Patent Number
NF1676L-25565
Meeting Information
Meeting: AHS International Annual Forum and Technology Display
Location: Fort Worth, TX
Country: United States
Start Date: May 9, 2017
End Date: May 11, 2017
Sponsors: American Helicopter Society International
Funding Number(s)
WBS: WBS 031102.02.07.08.91X0.16
Distribution Limits
Public
Copyright
Public Use Permitted.
No Preview Available