Multiobjective optimization of a tubular pump to improve the applicable operating head and hydraulic performance

Abstract

Tubular pumps are widely used in irrigation and water conveyance projects. However, the operating head of most of these pumps is low, and only a few studies have focused on the design of an efficient tubular pump with a head more than 5 m, which is common in long-distance water supply projects. This work aims to improve the operating head and efficiency of tubular pumps while maintaining a low shaft power. The multi-objective orthogonal optimization method was used to determine the critical parameters of the tubular pump, i.e., blade number, airfoil, blade thickness and guide vane distance, and nine design schemes were selected. Next, by using computational fluid dynamics (CFD), a 3D model of the tubular pumps under different schemes was established, and the results were compared. Subsequently, the range method and weighted matrix method were utilized to find the optimized scheme. In addition, an experimental investigation was performed to verify the simulation and the performance of the designed tubular pump. The results indicated that the optimized scheme improved the operating head to 6.9 m with higher efficiency of 84.2% and a lower shaft power of 27.7 kW. The modeling results were in agreement with the experimental measurements, and the designed tubular pump had a wide range of high-efficiency zones.

Dynamic stress characteristics and fatigue life analysis of a slanted axial-flow pump

“…The load on the blade mainly includes inertial force and flow field water pressure, and the inertial force is composed of centrifugal force and gravity. Referring to the research ideas in Kan et al 14 and Zhao et al 25 the calculation steps of flow field and structural field are consistent with the rotation period. In this paper, the rotation of 3° is taken as a time step, a period of 120 steps, and the time step is 0.002 s, while ensuring the stable flow of flow field, the computer hardware memory should also be taken into account, the total calculation time is 5 rotation cycles.…”

“…In the optimal flow rate condition, the y + value of each flow passage component of the slanted axial-flow pump device studied in this paper is: the y + value of the elbow inlet conduit is about 289, the y + value of the impeller is about 28, the y + value of the guide vane is about 53, and the y + value of the straight outlet conduit is about 201, which meets the requirement of the conclusion y + obtained from the numerical value calculation and research of the pump device in Reference. 25…”

Investigation on the Effect of the Shaft Transition Form on the Inflow Pattern and Hydrodynamic Characteristics of the Pre-Shaft Tubular Pump Device

“…The shear-stress transport (SST) k-ω (Zhao et al, 2021) turbulence model can modify the turbulent viscosity equation. Thus, the shear stress on the wall and the flow in the near-wall region are better transferred and predicted.…”

Hydrodynamic characteristics of lateral withdrawal with effects of the slope ratio

“…The 3-D numerical simulation of lateral withdrawal was based on the incompressible continuity and momentum equations. The governing equations are as follows (Park et al 2006;Zhao et al 2020):…”