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In consideration of the turbulent inflow condition of engineering applications, the flow mechanisms of dynamic stall of a tubercled airfoil have been comprehensively analyzed with an upstream cylinder. Numerical simulation of the flowfield of a tubercled wing with NACA0021 (National Advisory Committee for Aeronautics) airfoil has been conducted with the large eddy simulation model. Then, flow mechanisms have been analyzed based on the aerodynamic performances and flow structure descriptions. Meanwhile, proper orthogonal decomposition (POD) analysis has been carried out at both trough and peak sections to reveal the flow dynamics. It turns out that the dynamic stall process vanishes, and performances would be obviously impacted by the incoming cylinder wake in the case of [Formula: see text] due to the enforced resistance of adverse pressure gradient. Furthermore, the first leading POD mode corresponds to the pitching movement at both trough and peak sections, while the high-order modes represent the influence of cylinder wake. Eventually, the influence of pitching amplitude has also been discussed in the case of [Formula: see text]. Different from the case of [Formula: see text], dynamic stall phenomenon emerges, and the influence of wake impingement could be barely detected from the mode information except for the third mode at the trough section. The detachment of the dynamic stall vortex takes place corresponding to the dynamic stall onset, which is driven by the streamwise pressure gradient near the trough leading-edge.

Smart structures based on shape memory polymer composites (SMPCs) have attracted extensive attention because of their unique self-deployment behavior. This study investigated the thermal design and analysis of the SMPC flexible solar array system (SMPC-FSAS). The thermal design ensured the reliability of the deployment functionality and desirable structural temperatures. The fundamental properties of the shape-memory materials were obtained by dynamic mechanical analysis and shape fixity ratio tests. Thermal experiments, including the thermal balance test (TBT), thermal vacuum test and thermal cycle test were conducted to verify the safety and reliability of the SMPC-FSAS. Additionally, the temperature distribution of the SMPC-FSAS was simulated using numerical analysis. Notably, a geostationary satellite carrying the SMPC-FSAS was successfully launched into a geosynchronous orbit and controlled deployment was accomplished for the first time. The prediction of the numerical model was consistent with the TBT and on-orbit data, thus validating the accuracy of the numerical method. The research in this work has important reference significance for ultra-large SMPC-FSAS in the future.