AERODYNAMIC CHARACTERISTICS OF FLOW OVER BOAT-TAIL MODELS AT SUBSONIC AND SUPERSONIC CONDITIONS
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https://doi.org/10.54939/1859-1043.j.mst.75A.2021.60-69Keywords:
Aerodynamic drag; Boattail.Abstract
In this study, the flow behavior and drag of the axisymmetric model at subsonic and supersonic speeds were investigated by a numerical approach. The numerical results were validated with previous experimental results to determine the model's accuracy. The numerical results showed that the optimal angles reduce from 14° at subsonic conditions to 6° ÷ 8° at supersonic conditions. At the supersonic speeds, shock waves occur at the head and boat-tail of the model, which leads to changes in the pressure distribution and drag of the model. The flow behavior and velocity distribution around the model were investigated and presented in detail in this study.
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