Abstract
We design optimization on the overall blade structure of a vortex pump conducted by using the orthogonal test method to clarify the matching relationship of impeller and casing structures and then improve the hydraulic performance of the vortex pump. Based on two different impeller structures of forward-deflecting (denoted as R1 − F2) and backward-deflecting (denoted as F1 − R2), key parameters describing the impeller structure are calculated through optimization for the objective function of hydraulic efficiency by means of orthogonal tests and computational fluid dynamic simulations. Optimization computations show that the forward-deflecting blade impeller is superior to the backward-deflecting one. Model test of the optimized vortex pump is carried out calculating the error from the comparison of pump efficiencies calculated by model test and numerical simulation is calculated to be less than 6%. The experimental verification shows that the flow simulation has some errors. The weight of structure parameters such as the blade installation angle (α), the blade deflecting angle (β), the position of blade deflecting point (L), the radius (r) of smoothing arc at the deflecting point, the wedge type (W) of blade, to the lift head, the flow rate, and the efficiency of the pump is investigated, through multiparameter optimizations. Visualization observation of flows in the model pump consisted of a back-placed impeller and a front vaneless chamber is further performed. The characteristic of vortex formation predicted by flow simulation agrees with the result of visualization observation. The above results demonstrate that the optimum impeller type of vortex pump is forward-deflecting blade impeller. The optimum combination of the key structure parameters is that the deflection angle of the blade inlet (α) equals 30°, the position of blade deflecting point lM = 2/3 L, the chamfering radius (r) at the deflecting point r = 3 mm, and the best wedge type is axial deflecting blade.
Highlights
Vortex pumps used for transporting suspensions such as pulp solutions with short fibers are quite different to the traditional pumps in pump structure and flow pattern [1]
In 1954, the first vortex pump with WEMCO was developed by Western Machine Company. en the company Sterbery-Flygt in Sweden trial-produced the first vortex pump [2], and Rutschi published the first literature on vortex pump [3]
The important order of relevant factors affecting the head of backward-deflecting blade at the maximum efficiency point is as follows: the position of blade deflection point (M), the deflection blade types of wedge (W), the deflection angle of blade inlet (α), and the chamfering radius size (r) of blade deflection point, with the optimal combination being A1B3C2W1
Summary
Vortex pumps used for transporting suspensions such as pulp solutions with short fibers are quite different to the traditional pumps in pump structure and flow pattern [1]. The main structural characteristic of vortex pump is that an impeller is placed behind the volute casing and a vaneless chamber is arranged in front of the impeller. In 1954, the first vortex pump with WEMCO was developed by Western Machine Company. In the light of internal flow characteristics and mechanism of vortex pump, Schivley et al established a flow model based on the experiments of predecessors [4,5,6]. Research results of modern vortex pump have been published continuously under the persistent efforts of numerous scientific researchers
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
