Aerodynamic investigation of a model scale helicopter rotor in ground effect

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2017

Author

Şahbaz, Mehmet

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In this thesis, ground effect issue which is a vital topic for helicopter industry is investigated with model scale.For this purpose, a test setup with model helicopter rotor is established. With setup, ground effect is investigated with inclined ground and ground without inclination. Thrust and torque values are obtained for different rotation speeds with constant collective pitch. Comparison with literature is done and reliability of the test setup is proven. Inclined Ground Effect and Ground Effect with extreme proximity scenarios are tested. The proper trends of the performance parameters in these scenarios are obtained. For the sake of performance parameter alterations, CFD (Computational Fluid Dynamics) Method is applied to analyze the rotor downwash. To model the rotating helicopter blade, Single Moving Reference Frame Method (SMRF) is used. In this method, the blade and background mesh are kept still and rotational velocity is defined at each cell in the domain. With CFD results, flow physics is studied and performance changes in ground effect are explained.

Subject Keywords

Rotors (Helicopters)., Ground-cushion phenomenon., Computational fluid dynamics., Helicopters

URI

http://etd.lib.metu.edu.tr/upload/12621680/index.pdf
https://hdl.handle.net/11511/26881

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Şahbaz, “Aerodynamic investigation of a model scale helicopter rotor in ground effect,” M.S. - Master of Science, Middle East Technical University, 2017.