Pressure pulsations are crucial data within the flow field of a pump, and the characteristics of these pulsations can reveal changes in the internal flow. Based on model experiments, this paper obtained pressure pulsation data under two blade conditions and compared direct time-domain observations, peak-to-peak value changes, and the VMD decomposition method. The results show that even when it is known that one blade condition...

As a low-head and non-drive pump, the head reduction and stall advance are the key factors that restrict the popularization and application of the full tubular pump (FTP). In this paper, the shear stress transport (SST) k-ω turbulence model is used for the numerical calculation of the FTP. Additionally, based on the entropy generation theory, the energy loss and main distribution zones of the FTP under all working conditions a...

The large axial flow pump systems used in coastal pump stations are often required to add flap valves to the gates to improve the quality of the transition process. However, due to the unclear mechanism of the additional flap valve on the transition process of the large axial flow pump system, there are many difficulties in the design and application of this feature. In this paper, six kinds of flap valves with different areas...

Large axial flow pump systems (LAPS) are widely used in coastal pump stations. In the actual operation of a LAPS, various accidents often occur during shutdown due to the unreasonable control of stop flow measures such as the gate. In this paper, based on the secondary development of Flowmaster numerical software, a numerical simulation study was conducted on the shutdown process of a LAPS with different gate control laws. It...

A bi-directional pump is designed by using S-shaped hydrofoil, is the most convenient way to achieve bi-directional operation. In this paper, high-speed photography is used to visualize the flow field characteristics of the bidirectional pump under different cavitation numbers, and the flow field changes caused by cavitation are quantitatively analyzed in combination with the pressure pulsation sensor. The results show that th...

Large axial flow pump systems are used in coastal pump stations. It is common and very dangerous for large axial flow pump systems to encounter the failure of the fast hydraulic gate during start-up operations. Methods for equipping LAPS with reasonable safety aids for start-up operations in order to deal with the unexpected situation that the quick gate cannot be opened, limiting the safety and stability of LAPS, have become...

The S-shaped hydrofoil is often used in the design of reversible machinery due to its centrally symmetrical camber line. The objective of this paper is to study the influence of cloud cavitation on the flow structure and the unsteady characteristics of lift and drag around an S-shaped hydrofoil via experimental tests and numerical simulations. In the experimental component, the tests were carried out in a cavitation tunnel and...

In order to study the evolution characteristics of suction-side-perpendicular cavitating vortex in an axial-flow pump under low flow conditions, model tests, high-speed imaging, and an SST-CC turbulence model were used to simulate the external characteristics and cavitation morphology of the pump. The evolution law of suction-side-perpendicular cavitating vortex (SSPCV) was revealed by turbulent kinetic energy, liutex vortex i...

In order to study the influence of the position of the bulb on the hydraulic performance of a submersible tubular pump device, based on a large-scale pumping station, two schemes—involving a front-mounted bulb and a rear-mounted bulb, respectively—were designed. The front-mounted scheme uses the GL-2008-03 hydraulic model and its conventional guide vane, while the rear-mounted scheme uses the optimized design of a diffuser van...