Pressure distribution on helicopter fuselage

Abstract

Modern rotorcrafts are subjected to some of the most complex flow behaviors ever encountered by the rotorcraft aerodynamicist. The objective of this research work is to investigate the pressure distribution on a helicopter fuselage in relation to the helicopter phenomenon. In this experimental work, a standard ellipsoidal helicopter fuselage model was mated to a main-rotor-hub assembly from a remote-control helicopter. The model was equipped with 28 pressure taps where the locations of the taps were predetermined by CFD analysis. The experiments were carried out in the UTM wind tunnel with a test section of 2m (width) x 1.5m (height) x 5.8m (length) with the maximum wind speed of 80 m/s. Data of pressure corresponding to the variations of helicopter’s pylon configurations and advance ratios were recorded using Electronic Pressure Scanning System. The effects of advance ratio and pylon configuration to the pressure distribution on helicopter fuselage were analysed. Findings reveal that the employment of pylon does augmenting the pressure coefficient on the rear part of the fuselage. Results also indicate the pressure distributions on the right and left sides of the fuselage are unsymmetrical indicating a very complex flow phenomenon experienced by the helicopter fuselage.