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The optimization of pumping station inlet channels is a key research area for improving the operation efficiency, reducing the energy consumption, and enhancing the operation reliability of pumping stations. For the elbow inlet channel of the Majinggang Pumping Station project, based on the Stress-Blended Eddy Simulation (SBES) turbulence model and entropy generation theory, an optimization design plan is proposed by altering the inclination angle of the flow channel base plate, the length of the transitional arc segment, and the length of the curved segment. Various schemes were analyzed and comprehensively compared in terms of the hydraulic loss, the velocity-weighted average angle, and the axial-velocity distribution uniformity of the channel. The results indicate that optimal hydraulic performance is achieved when the inclination angle of the base plate is between 8° and 10°. In a reasonable range of values, appropriately increasing the length of the transitional arc and reducing the section width (throat width) can improve the hydraulic performance of the inlet channel. The optimal model obtained achieved an impressive velocity-weighted average angle of 89.25°, along with an axial-velocity distribution uniformity of 97.5%. Its excellent hydraulic performance not only meets the design requirements of the pumping station in terms of functionality but also takes into account economic efficiency, and it serves as a valuable reference for similar projects, contributing to the more refined and intelligent development of the optimization of pumping station inlet flow channels. [ABSTRACT FROM AUTHOR]

As fire safety issues receive increasing attention, the development of efficient flame-retardant materials has become particularly important. This study explores the preparation methods of nano-violet phosphorus (NVP) and nanocellulose (NCC) composite films and their superior performance in flame retardancy applications. NVP was successfully prepared using a liquid-phase exfoliation method and was then non-covalently self-assembled with NCC to form a novel composite film with good uniformity. The microstructure, mechanical properties, and flame-retardant performance of the composite film were comprehensively characterized. The results indicated that the NVP/NCC composite film with only 1 wt% NVP exhibited significantly enhanced self-extinguishing capability (<2 s) and a peak heat release rate (23.31 kW m−2) and total heat release (1.78 MJ m−2), indicating its effectiveness in delaying the combustion process under flame exposure. The introduction of NVP made the decomposition rate of the composite film slower and the decomposition behavior more stable in an aerobic environment. In addition, the presence of NVP delayed the dehydration process of NCC, and promoted the carbonization reaction, thereby reducing the release of H2O, thus forming a protective carbon layer and removing active free radicals, significantly improving the thermal stability and safety of the composite. This work provides important theoretical foundations and practical guidance for the development of new flame-retardant materials. [ABSTRACT FROM AUTHOR]