Informatics Publishing Limited

Syed Mohammed Musharraf ¹, Srinivas G ¹

Affiliations
1 Department of Aeronautical and Automobile Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education (MAHE), Manipal, Udupi, Karnataka, India 576104., IN

Abstract

The majority of hypersonic vehicle designs focus on reducing drag and controlling flow enthalpy. Aerodynamic drag is caused by high surface pressure, which creates a detached bow shock in ahead of the blunt nose. These flow separation bow shocks impact hypersonic vehicle speed, range, and heating. Converting the detached shockwave to an attached shock wave (family of the weaker shock) and keeping the dissipation area large enough for a higher heat dissipation rate is a straightforward way to solve aerothermodynamics problems. The most popular technique involves introducing an antenna-like structure known as an Aerospike, placed right at the stagnation point over the blunt head. The aerospike contributes to the generation of the attached shock wave, which reduces the pressure drag component and results in recirculation zones over of the nose. This paper evaluates the performance of an aerospike hypersonic vehicle under various off-design conditions using the ANSYS Fluent software. Flow simulations are validated with available experimental data and tested under various turbulence models. All numerical simulations of the vehicle with aerospike are studied in detail, including flow properties such as pressure, temperature, density, turbulence model, etc. The paper concluded that drag reduction results under specific flow conditions were achieved by incorporating the aerospike into the hypersonic vehicle. Furthermore, this paper also contributes to the future research field of hypersonic aeromechanical engineering.

Keywords

Aerospike, Computational Fluid Dynamics (CFD), Drag Reduction, Shock Wave, Recirculation Zones.

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Vanshika Gupta ¹, Srinivas G ¹

Affiliations
1 Department of Aeronautical & Automobile Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education (MAHE), Manipal, Udupi, Karnataka, IN

Abstract

The ever-increasing demands of humanity have given rise to numerous innovative technological advances in each and every field throughout history. Aviation is one such field, and future demands in air transportation, such as noise reduction, improved aerodynamic performance, lower operating costs, higher fuel efficiency, and so on, led aircraft designers to conceptualize the Blended Wing Body (BWB). The BWB has proven to be more aerodynamic and efficient than conventional designs. This paper attempted to evaluate BWB performance using various numerical techniques. This study aims to contribute to the emerging research in this field by verifying previous results on a baseline BWB design and improving them through numerical model optimization. The baseline BWB model has been numerically simulated at various angles of attack ranging from 0o to 40o and low subsonic Mach numbers to determine its, lift to drag ratio, and thus its aerodynamic efficiency under these conditions. The baseline model has been modified by adding winglets, and changing the sweep angle and airfoil used for the outer wing. For this optimized model, numerical simulations with boundary conditions similar to the baseline have been run, and the results have been compared and validated with the baseline. All numerical simulations of the BWB vehicle were thoroughly investigated, including flow properties such as pressure, temperature, density, turbulence model, and so on. The results of this study have also been compared to a traditional flight to highlight the enhancements in the aerodynamic performance provided by the BWB configuration.

Keywords

Blended wing body (BWB), Computational fluid dynamics (CFD), Aerodynamic efficiency, Drag coefficient, Angle of attack.

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