Assessment of Tip Planform Effects on Hover and Forward Flight Aerodynamics of Helicopter Rotors

Chong Zhou

22 Pages

Directed by Dr. Lakshmi N Sankar

An Assessment of Tip Planform Effects on Hover and Forward Flight from physical point of view is proposed. Preliminary studies have already been completed to assess the effects of planform tip shape on hover performance. The flow field including sectional loads, tip vortex trajectories, and inflow velocity distributions will be examined to identify underlying physical phenomena that influence the previously documented changes to the rotor performance in hover.

Furthermore, all configurations considered in hover will be analyzed in forward flight at a specific advance ratio and shaft incidence angle representative of S-76 which is the baseline of the study, and the rotors will be trimmed for specified thrust values and zero hub moments. It would be examined whether configurations that are efficient in hover are also efficient in forward flight from an induced power and profile power perspective.  The sectional airloads and integrated hub loads will be analyzed to determine whether the changes to the tip shape favorably or adversely affect the vibratory loads.  Underlying physical phenomena (dynamic stall, blade vortex interaction, tip stall) will be identified.

It is on Friday Oct. 13th at 10AM Weber Room 200

Committee:

Prof. Lakshmi N Sankar, Prof. Daniel P Schrage and Prof. Jonnalagadda V R Prasad