Development of a design method for subsonic intakes with improved aerodynamic performance and reduced radar signature

Ünlü, Tezcan
In this thesis, a design method for a subsonic intake with high aerodynamic performance and reduced radar signature is developed. Intakes are key components of aircrafts’ propulsion systems that create open ended cavities resulting in increased radar signature. To achieve reduced radar signature characteristics, a parameterized double curved intake is proposed. Due to the nature of this multi-objective and multi-disciplinary engineering problem, surrogate based analysis and optimization approach is taken to reduce the computationally expensive and time consuming analyses. The thesis consists of three main sections. In the first section, validation studies for the intake performance evaluation methods are conducted. Mesh independence and turbulence model selection studies are carried out for the computational fluid dynamics analyses and radar cross section evaluation studies are carried out for the electromagnetic analyses. In the second section, a design problem is constructed and the verified analyses methods are used for the performance evaluation of the design points required by the surrogate model. Then the best performing design in terms of aerodynamics and radar cross section is obtained with an optimization study. In the last section, analyses with high fidelity prediction tools are conducted for the validation of the obtained design and the design method. Results showed that the surrogate based model is successful at the prediction of performance indicators and can be used for intake optimization purposes. Lastly the performance of the best design is investigated with post-process outputs revealing competitive results regarding aerodynamics and radar signature.


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Citation Formats
T. Ünlü, “Development of a design method for subsonic intakes with improved aerodynamic performance and reduced radar signature,” M.S. - Master of Science, Middle East Technical University, 2021.