Vortex generator design for subsonic inlets

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2014
Nasuhbeyoğlu, Batuhan
In this thesis, numerical investigation of the benefits of vortex generators control on the performance of S-shaped inlets has been performed. This study is divided into two main parts. In the first part, a diffusive S-shaped inlet is examined and the numerical analyses results are compared with the experimental results. Three-dimensional Navier-Stokes equations are solved and three different turbulence models which are Realizable k-ε, Standard k-ω, and Spalart-Allmaras methods are used. Distortion coefficient and pressure recovery results at aerodynamic interface plane (AIP) are compared with experimental results and both of them are in good agreement. In the second part, a parametric design study for vortex generators are carried out in order to investigate possible effects of vortex generators on performance of the inlet, and results of the analyses are compared with the inlet without vortex generators. Inlet performance parameters which evaluate vortex generator efficiency are pressure recovery, distortion coefficient and mass flow rate at AIP. Several parameters such as device size, quantity and location are analyzed and an optimal configuration is chosen. Improvement on flow is observed for most of the configurations. For these configurations, value of pressure recovery is insignificantly reduced. On the other hand, there is a huge amount of improvement on distortion coefficient value. The aim of this study is to obtain a uniform flow as much as possible at engine interface plane with no or negligible amount of mass flow rate loss. More uniform flow is obtained by reducing the value of distortion coefficient and the amount of pressure recovery loss due to vortex generators is also acceptable in terms of mass flow rate loss.

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Citation Formats
B. Nasuhbeyoğlu, “Vortex generator design for subsonic inlets,” M.S. - Master of Science, Middle East Technical University, 2014.