Supersonic civil aircraft have become one of the important directions for the future development of civil aviation. For the rapid conceptual design and performance optimization of supersonic civil aircraft layouts, an aerodynamic optimization framework for transonic and supersonic dual-cruise regimes was developed using a medium-fidelity solver based on the Euler equations with boundary layer correction to ensure computational efficiency while capturing key flow features. Using this framework, the baseline configuration was optimized, and the optimization results were selected from the Pareto optimal solution set in the dual-speed domain. Building on this, a high-precision low-drag adjoint optimization based on RANS equation for the wing-body combination was carried out under supersonic conditions, resulting in drag reductions of 43.4 counts at Ma = 0.9 and 54.1 counts at Ma = 1.8. To further address the multidisciplinary design challenge of simultaneously minimizing both drag and sonic boom intensity, a prediction method combining ray tracing technique and augmented Burgers equation was employed to simulate the propagation of near-field sonic boom signals. The ground waveforms were analyzed using the Mark VII criteria developed by Stevens to calculate the perceived loudness in decibel (PLdB) of the sonic boom. A multidisciplinary optimization framework considering both aerodynamic performance and sonic boom signals at different azimuthal angles was established to achieve a low-drag and low-sonic boom design. The optimization results showed that, compared to the baseline configuration, the final shape achieved comprehensive improvements in both drag and sonic boom performance throughout the entire sonic boom carpet region: The drag coefficient was reduced by 30.6 counts at Ma = 0.9 and by 50.3 counts at Ma = 1.8, while the average ground-level perceived loudness in decibel was reduced by 4.84 PLdB.

A 2% scale, cruising version of a 450-seat class Blended-Wing-Body (BWB) transport was tested in the China Aerodynamic Research and Development Center’s FL-26 2.4-by-2.4-meter subsonic wind tunnel. The focus of the wind tunnel test was to investigate the aerodynamic performance of the latest BWB transport design, which would also aid in choosing a final engine arrangement in the three most potential engine integration layouts. The wind tunnel model can be tested with and without the nacelle and has three sets of different nacelle/tail integration positions. Computational Fluid Dynamics (CFD) simulations were performed in engine-aircraft integration design to find appropriate nacelle installing parameters of each layout. The comparison of CFD with experimental results shows good agreement. Wind tunnel measurements indicate that the tail-mounted engine layout produces the minimum drag penalty, while the fuselage-mounted engine layout increases drag the most. Experimental pressure measurement illustrates the effect of nacelle integration on the wing-body surface pressure distribution. This experimental and numerical research provides a reference for future BWB Propulsion-Airframe Integration (PAI) design.