Nearfield Summary and Analysis of the Third AIAA Sonic Boom Prediction Workshop C608 Low Boom Demonstrator

A summary and statistical analysis of the nearfield Computational Fluid Dynamics (CFD) submissions for the Third AIAA Sonic Boom Prediction Workshop is provided with a focus on the C608 Low Boom Flight Test Demonstrator. The C608 is more complex in terms of geometry and propulsion boundary conditions than previous workshop cases and is more representative of vehicles with lower ground loudness and the potential for lower annoyance. The nearfield signatures submitted by the participants are propagated to the ground to compute statistics of loudness measures over the vehicle sonic boom carpet. Principle component analysis is used to extract the primary variation modes. Context from previous sonic boom workshops indicates that this workshop has the lowest variation even though the case is more challenging because it is quieter and more complex. The results documented in this summary indicate that the international state-of-the-art for nearfield CFD has a variation that is small enough for meaningful low-boom design and analysis. Low-boom configuration analysis methods with low variation are important tools to develop certification processes for addressing the prohibition on overland supersonic commercial flight.