Modern agriculture requires much greater energy input than conventional agriculture, which heavily depends on fossil fuels for drying grain, manufacturing fertilizers, driving machinery, and generating electricity used for heating and lighting purposes. As the SG speed increased, pressure fluctuations gradually decreased at various locations across the SAFP. Due to the gravitational effect of the slanted structure, the fluctuation of the runner in vertical direction presented an off-axis characteristic compared with the horizontal one. Compared with the axial direction, moments in the radial directions were found with more obvious oscillation as a result of stronger rotor–stator interaction. The water hammer effect was simulated with different shut-down speeds, increasing the water head by 5.07–10.42 m, the axial force by 163.46–297.06 kN∙m, and the axial moment by 116.05–224.01 kN∙m. Reducing the shut-down speed leads to a greater reverse flow rate and higher runner speed. Our analysis demonstrated that both the shut-off conditions and the slanted structure have conspicuous impacts on the hydrodynamic performance of a SAFP. Multiple shut-off conditions with various shut-down speeds of the sluice gate (SG) were modeled. In this study, to reveal the transient characteristics of a SAFP at shut-off conditions, a computational fluid dynamics (CFD) based approach with dynamic mesh was proposed. As a critical component of a pumping station, a large-scale slanted axial-flow pump (SAFP) featuring high specific speed plays a critical role in mitigating urban flooding and waterlogging. Increasing extreme rainfall events caused by global climate change have had a significant impact on urban drainage systems. Reproduced with permission from Food and Agriculture Organization of the United Nations © FAO (). Cropped from the original (d) Schematic view of a TMPT. Reproduced with permission from Wayne Perkins. White ( ID=2076) (c) Hydrobine in operation. © The Alternative Technology Association () (b) Illustration of a Turbopump in operation. Reproduced with permission from Alternative Technology Association Inc. © EB Engineering Solutions Different types of tubular multi-propeller turbines (TMPTs): (a) Plata pump. Different types of tubular multi-propeller turbines (TMPTs): (a) Plata pump.
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