A numerical investigation of helicopter flow fields including thermal effects of exhaust hot gases

Gürsoy, Zeynep Ece
This thesis investigates the flow field of a twin-engine, medium lift utility helicopter numerically. The effects of the exhaust hot gases emerging from the engines are accounted for in the numerical study. The commercial computational fluid dynamics (CFD) software ANSYS Fluent is employed for the computations. While the effects of engines are included in the computations through simple inlet and outlet boundary conditions, the main and tail rotors are simulated by the Virtual Blade Model in a time-averaged fashion. Forward flight at four different advance ratios and hover in ground effect are studied. The temperature distribution around the tail boom is compared to available flight test data. Good agreement with the flight test data is observed.


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Yalçın, Mehmet Efruz; Yaman, Yavuz; Department of Aerospace Engineering (2009)
In this study, equipment rack structure for a medium transport aircraft was designed and finite element analysis of this design was performed. The equipment rack structure, which was designed for a modernization project, was positioned and dimensions were determined by regarding the geometry of primary structures of the aircraft. The structure was designed such that it satisfies the pre-defined margin of safety values. Design of the structure was prepared in Unigraphics, and the finite element modeling and ...
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Dizemen, İlke Evrim; Yörükoğlu, Yusuf; Department of Aerospace Engineering (2007)
This study, explores the use of an iterative solution approach for the linearized Euler equations formulated in the frequency domain for fan tone noise propagation and radiation through bypass jets. The aim is to be able to simulate high frequency propagation and radiation phenomena with this code, without excessive computational resources. All computations are performed in parallel using MPI library routines on a computer cluster. The linearized Euler equations support the Kelvin-Helmholtz type convective ...
Experimental and numerical investigation of flow field around flapping airfoils making figure-of-eight in hover
Başkan, Özge; Alemdaroğlu, Hüseyin Nafiz; Department of Aerospace Engineering (2009)
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Investigation of rotor wake interactions in helicopters using 3d unsteady free vortex wake methodology
Yemenici, Öznur; Uzol, Oğuz; Department of Aerospace Engineering (2010)
This thesis focuses on developing and examining the capabilities of a new in-house aerodynamic analysis tool, AeroSIM+, and investigating rotor-rotor aerodynamic interactions for two helicopters, one behind the other in forward flight. AeroSIM+ is a 3-D unsteady vortex panel method potential flow solver based on a free vortex wake methodology. Validation of the results with the experimental data is performed using the Caradonna-Tung hovering rotor test case. AeroSIM+ code is improved for forward flight cond...
Near-surface topology of unmanned combat air vehicle planform: Reynolds number dependence
Elkhoury, M; Yavuz, Mehmet Metin; Rockwell, D (American Institute of Aeronautics and Astronautics (AIAA), 2005-09-01)
The Reynolds number dependence of the near-surface flow structure and topology on a representative unmanned combat air vehicle planform is characterized using a technique of high-image-density particle image velocimetry, to complement classical dye visualization. Patterns of streamline topology, including bifurcation lines, as well as contours of streamwise and transverse velocity, surface-normal vorticity, and Reynolds stress correlation, all immediately adjacent to the surface of the planform, provide qua...
Citation Formats
Z. E. Gürsoy, “A numerical investigation of helicopter flow fields including thermal effects of exhaust hot gases,” M.S. - Master of Science, Middle East Technical University, 2009.