Experimental Investigation of Impacting Flow between a Sub-Scale Twin-Rotor Configuration

  • Ali Mehrabi Department of Aerospace Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
  • Ali Reza Davari Department of Aerospace Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
Keywords: semi-quiescent, impacting flow, ground effect, twin-rotor configuration, pressure distribution

Abstract

In this paper, a series of experiments have been performed to understand the semi-quiescent and the impacting flow structure beneath the twin-rotor configuration body using a multipurpose test stand with a sub-scale model airframe in the ground effects. So, the main purpose was to perform a qualitative investigation on the recirculated impacting flow between the twin-rotors. Pressure and velocity measurements were performed by the pressure ports embedded longitudinally along the airframe. The results show that for a single rotor an impinging jet-like small region and rearward and upward flows were below the body. The presence of the second rotor in configurations causes an impacting flow formation in the longitudinal center region below the airframe and a semi-quiescent flow formed there. The positive effects of this flow includes increasing the sub-body pressure and lifting force, the pressure distribution balance, and desirable pressure gradient on sidewalls of the airframe. Tuft tests observations confirm that the location of the impacting flow formation is affected by the pressure and velocity measurements. The mentioned impacting flow aerodynamic effects must be taken into account in design of the flight controls trims and stability systems of twin-rotor configurations.

Author Biography

Ali Reza Davari, Department of Aerospace Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

Associate Professor, Corresponding author

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Published
2020-07-01
How to Cite
[1]
A. Mehrabi and A. R. Davari, “Experimental Investigation of Impacting Flow between a Sub-Scale Twin-Rotor Configuration”, Int. j. eng. technol. innov., vol. 10, no. 3, pp. 211-224, Jul. 2020.
Section
Articles