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Theoretical model and experiment on rotor in finite ground effect
Received date: 2016-03-14
Revised date: 2016-07-25
Online published: 2016-08-22
Supported by
National Natural Science Foundation of China (51405227)
A new flow-field analysis model for the finite ground effect of the rotor is developed. Considering the complexity of the ground effect caused by finite ground, a "material line" rectification method is proposed to solve the problem that part of wake vortices may non-physically "penetrate" the finite ground in discrete prediction, and a high stability time-stepping free-wake algorithm with 3rd-order accuracy is introduced into the model. Considering the shortage of existing experimental data for finite ground effect, a finite ground effect experiment research is also implemented, and the thrust, torque and flap angle of a hovering and flying rotor are measured. The experimental data validates the analysis model proposed in this paper. According to the wake geometry got from theoretical model, several flying states of rotor in finite ground effect are analyzed, and some reasonable conclusions are gained.
Key words： rotor; finite ground; time-stepping; free-wake; wake rectification
XIN Ji , LI Pan , CHEN Renliang , LIU Dawei . Theoretical model and experiment on rotor in finite ground effect[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2017 , 38(3) : 120219 -120219 . DOI: 10.7527/S1000-6893.2016.0221
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