Significant aerodynamic interference can occur between high-speed bodies in close proximity. A complex flowfield develops where shock and expansion waves from a generator body impinge upon the adjacent receiver body. The pressure and flow angularity changes which occur across these disturbances modify the body aerodynamics. The aim of this research is to quantify the aerodynamic interference effects for multi-body configurations and understand the relevant flow physics.The interference aerodynamics for slender bodies in a supersonic flow were investigated through a parametric wind tunnel study. The receiver bodies were finned and un-finned configurations. The effect of lateral and axial body separations, receiver incidence and the strength of the disturbance field were investigated. Measurements included forces and moments, surface pressures and flow visualisations. Supporting computations using steady-state, viscous predictions provided a deeper understanding of the underlying aerodynamics and flow mechanisms. Good agreement was found Many people have contributed to the completion of this research. I would like to take time to thank them. My supervisor David MacManus for his guidance and help throughout. I would especially like to thank him for the many occasions when he took my work home with him to read and provide feedback during the writing process. I would like to acknowledge the financial support of the UK MOD. The investigation which is the subject of this report was initiated by the Air Systems Department Dstl and was carried out under the terms of Contract No RD025 -1962. Additional funding was also provided through an ESPRC CASE award. I would also like to thank Dstl for the release of experimental data which greatly enhanced this research. Trevor Birch for his constant support and guidance throughout. In particular, I would like to thank him for making arrangements for me to undertake two placements at Dstl. These aided my research and I enjoyed my time at Dstl immensely. Moreover, I would like to also thank Ben Shoesmith and Kristian Petterson who gave up alot of their own time in order to assist me. Their help with IMPNS and Cobalt was particularly useful.

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Aerodynamic interference can occur between high-speed bodies when in close proximity. A complex flowfield develops where shock and expansion waves from a generator body impinge upon the adjacent receiver body and modify its aerodynamic characteristics. The aims of this paper are to validate a computational prediction method, to use the predicted solutions to interpret the measured results and to provide a deeper understanding of the associated flow physics.

Aerodynamic interference can occur between high-speed slender bodies when in close proximity. A complex flowfield develops where shock and expansion waves from a generator body impinge upon the adjacent receiver body and modify its aerodynamic characteristics in comparison to the isolated case. The aim of this research is to quantify and understand the multi-body interference effects which arise between a finned slender body and a second disturbance generator body. A parametric wind tunnel study was performed where the effects of receiver incidence and axial stagger were considered. Computational Fluid Dynamic simulations showed good agreement with the measurements and these were used in the interpretation of the experimental results. The overall interference loads for a given multi-body configuration are found to be a complex function of the pressure footprints from the compression and expansion waves emanating from the generator body as well as the flow pitch induced by the generator shockwave. These induced interference loads change sign as the shock impingement location moves aft over the receiver and in some cases cause the receiver body to become statically unstable. Overall, the observed interference effects can modify the subsequent body trajectories and may increase the likelihood of a collision. Nomenclature a = sonic velocity, ms -1

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