Experimental investigation into the aerodynamics of Hammerhead launcher configurations in transonic regime
As the space industry continues to grow rapidly, the development of reusable launch vehicles has become crucial in achieving cost-effective and sustainable access to space. Payload capacity optimisation has been at the forefront of this effort, leading to a renewed interest in hammerhead or bulbous...
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| Tipo de recurso: | tesis de maestría |
| Fecha de publicación: | 2023 |
| País: | España |
| Institución: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/402325 |
| Acceso en línea: | https://hdl.handle.net/2117/402325 |
| Access Level: | acceso abierto |
| Palabra clave: | Rockets (Aeronautics) Aerodynamics PIV Schlieren Aerodinàmica Separació de flux Flux transònic Oil flow visualisation Hammerhead configuration Coets (Aeronàutica) Àrees temàtiques de la UPC::Aeronàutica i espai::Aerodinàmica |
| Sumario: | As the space industry continues to grow rapidly, the development of reusable launch vehicles has become crucial in achieving cost-effective and sustainable access to space. Payload capacity optimisation has been at the forefront of this effort, leading to a renewed interest in hammerhead or bulbous payload fairing (PLF) configurations. These designs feature a larger diameter in the PLF than in the rest of the launch vehicle, enabling the same structure to be used for large payloads. However, the transonic regime poses unique challenges for these PLFs due to their susceptibility to flow separation and strong pressure fluctuations. This master thesis investigates the influence of nose and boat-tail geometries on flow phe-nomena, particularly shock wave generation, around hammerhead configurations in transonic conditions. The research was conducted through three distinct experimental campaigns in the transonic wind tunnel TST-27 at the high-speed laboratory of TU Delft, employing schlieren, oil flow, and Particle Image Velocimetry (PIV) techniques. The study revealed notable insights into the aerodynamics of the hammerhead PLF con-figurations. Boat-tails set at five and 15-degree angles were observed to broaden the range of shock wave oscillations, introducing an additional shock wave that could occasionally merge with existing ones. Moreover, the conic nose design induced higher shock wave oscillations, while the bi-conic nose introduced an extra shock wave compared to the conic and ogive noses. The study also found that altering the nose shape while keeping the boat-tail constant, or vice versa, resulted in similar effects on flow dynamics. These findings underscore the critical role that nose and boat-tail geometries play in shap-ing the aerodynamic behaviour of hammerhead PLF configurations. The results have impli-cations for such configurations’ design and stability considerations in transonic conditions. It was observed that raising the Mach number heightened shock wave oscillations and flow de-tachment. The angle of attack disrupted model symmetry, primarily impacting reattachment patterns. Furthermore, the conic nose exhibited greater unsteadiness due to oscillations in the shock waves compared to the other geometries. The study also provided detailed insights into shock wave spectral characteristics and identified potential influences of pressure wave oscil-lations on shock wave behaviour. The conclusions lead to recommend designs with bi-conic nose, and avoid boat-tail angles around 15 degrees. |
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