Iranian Journal of Mechanical Engineering Transactions of ISME

Iranian Journal of Mechanical Engineering Transactions of ISME

Experimental Study of the Ground Effects on Performance of Model Tandem-Rotor Helicopter in Hover Flight

Authors
Ali Mehrabi 1
Ali Reza Davari 2
javad Deldar Sheikhi 3
1 Helicopter engineering department, Engineering and flight faculty. Imam Ali Military University(IAMU), Tehran
2 Assistant Professor, Department of Engineering, Imam Ali University, Tehran, Iran.
3 emam ali university
10.30506/ijmep.2021.138137.1734
Abstract
The effect of ground proximity on the some performance parameters of tandem rotors was measured using a multifunctional test rig in this study. Trust, produced power and induced power measurements of the rotors were performed in three different overlap values ​​to investigate the effects of ground proximity on these values ​​in hover flight. The results showed that the positive effect of ground proximity on the produced trust of tandem rotors is more than single rotors. In the ground effect, as the amount of overlap of the tandem rotors increased and the effect of the fountain flow recirculated from the ground increased, the amount of thrust increased . The results of power measurements showed that with decreasing the height of the rotors in the ground effect, the amount of induced power as well as the negative effect of aerodynamic interference due to their overlap decreased, These findings lead to a new approach to evaluating the performance of this type of helicopters.
Keywords
Helicopter
Tandem rotors
Ground effect
Thrust
Induced power

Subjects

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  • Receive Date 14 October 2020
  • Revise Date 29 November 2020
  • Accept Date 11 January 2021