Effect of Impeller Trimming on the Energy Efficiency of the Counter-Rotating Pumping Stage

Abstract

Developing ways to increase centrifugal pumps’ pressure and power characteristics is a critical problem in up-to-date engineering. There are many ways to resolve it, but each has advantages and flaws. The presented article aimed to ensure higher energy efficiency indicators by using a counter-rotating pumping stage with trimming. During the research, the comprehensive approach was based on CFD modeling and the Moore–Penrose pseudoinverse approach for overestimated systems. According to the obtained data, pumps with a counter-rotating stage allowed the pressure head to be significantly increased compared with the standard design of the flow part. Notably, for pumping units CPS 180/1900 with a basic stage, the pressure head of 127 m was reached. However, when using a counter-rotating stage, the pressure head could be increased up to 270 m, which was 2.1 times higher. Therefore, to ensure unchanged characteristics when using centrifugal pumps with the counter-rotating stage, the weight and size indicators can be significantly reduced compared to the traditional design scheme. The proposed numerical and analytical approaches allow estimating the highest pressure and energy characteristics values.

Development of a High-Rotational Submersible Pump for Water Supply

“…Figure 7 shows the characteristics of the stage in different operating modes obtained using the quasilinear regression approach [29]. Figure 8 shows the flowing part's pressure and relative velocity distributions (model 01).…”

“…The operating environment was water with a temperature of 20 • C. The mode was turbulent. To conclude the Reynolds equations, the standard k-ε [28] turbulence model was used, which has proven itself well in conducting studies of the flow in the flow part of centrifugal pumps [29].…”

Improving the Performance of an Innovative Centrifugal Pump through the Independent Rotation of an Inducer and Centrifugal Impeller Speeds

“…Pavlenko et al [20] conducted a numerical study on the effect of the impeller trim in a counter-rotating centrifugal pump. They investigated various counter-rotating impellers and found that the pump's pressure is influenced by the impeller trim and the size of the working part of the impeller.…”