Herein, a twin-boom, inverted V-tailed unmanned aerial vehicle (UAV) featuring a foldable bi-wing configuration is proposed for logistics and transportation applications. We employed the NavierStokes solver to numerically simulate steady, incompressible flow conditions. By examining the effects of key design parameters on aerodynamic characteristics and bypass flow fields in a two-dimensional state, we were able to suggest a more optimized foldable wing design. Building on the two-dimensional analysis, we performed aerodynamic assessments of the three-dimensional aircraft geometry. Our results indicated that appropriate wing and gap parameters can significantly enhance lift characteristics, maintaining high lift even during large-angle flights. Specifically, when compared to a mono-wing, the lift coefficient of the bi-wing increased by 27.1 at a 14 angle of attack, demonstrating the effectiveness of our wing-and-gap design. Optimal aerodynamic performance was achieved when the gap distance equalled the chord length in both flow and vertical directions. Further, the right combination of airfoil configuration, wing axes angle, and wingspan can improve flow field aerodynamic characteristics, while also enhancing the wings stall capacity. The lift coefficient reached its maximum value at an angle of attack of 15, which has the potential to reduce takeoff and landing distances, thereby enhancing the UAVs overall safety.

The supercritical carbon dioxide (S-CO2) closed Brayton cycle holds significant promise for revolutionizing the future of efficient and comprehensive new energy utilization. However, the compressor operation in this cycle is characterized by rapid pressurization, which induces substantial fluctuations in temperature and pressure, potentially triggering non-equilibrium condensation of S-CO2. This phenomenon disrupts the flow field within the compressor, thereby decreasing the overall performance of the cycle system. Therefore, exploring this mechanism is of great significance for improving the performance of the cycle system. This work summarizes various improvement types of S-CO2 closed Brayton systems and engineering applications across various fields. Subsequently, it reviews the development of non-equilibrium condensation theories within S-CO2 compressors, focusing on the nucleation and growth models. In addition, the current research status of condensation characteristics of S-CO2 under high-speed and high-pressure conditions is summarized, based on convergent-divergent nozzle experiments and simulations. This work systematically reviews the progress in non-equilibrium condensation research within S-CO2 closed Brayton cycle system compressors, from various perspectives, such as the origin of the technological bottleneck, the nature of the scientific problem, and the current state of research. By reviewing the current status of the compressor blade humidity control method under non-equilibrium condensation, it is proposed that the technology of active blade humidity control based on multi-objective coordination should be the direction of further research. The findings of this analysis can provide a reference for the design and further research on compressor blades in the S-CO2 closed Brayton cycle system.