Computations of engine bypass in a wind tunnel configuration

Supersonic civilian air travel represents a major opportunity for aviation. The ability to mitigate the intensity of the sonic boom generated by commercial supersonic aircraft to comply with potential future aviation regulations is critical to realizing that goal. Computations of concentric engine bypass design were completed to simulate flow characteristics in a wind tunnel configuration. These studies represent a key aspect of a supersonic low-boom inlet. The bypass flow accounts for non-axisymmetric engine blockage and is an important component of a supersonic low-boom engine design. In conjunction with experiments, this study aimed to predict the detailed flow structures to help improve fairing performance around the engine blockage. Using FLUENT as a computational tool, studies were conducted to optimize computational time while capturing essential flow characteristics. The present study investigated the influence of wind tunnel conditioning on bypass flow, compared flow conditions of a baseline bypass model to experimental results, and is ongoing to optimize a fairing design which decease the pressure losses of a high flow bypass nacelle blueprint. The results showed that the flow conditioning reasonably provided a uniform axisymmetric flow upstream of the flow blockage regions. Current fairing simulation results demonstrate that the leading geometry of the fairing around the engine blockage provides a good flow diversion, however flow separates significantly at the rear. As such, the downstream portion of the fairing must be considered carefully in future studies to reduce pressure losses to improve performance of the design.