Calculation of flow in incompressible regenerative turbo-machines with bucket form blades based on the geometry of flow path

Abstract

Purpose

Regenerative flow pumps are dynamic machines with the ability to develop high heads at low flow rates. Simplicity, compactness, stable features and low manufacturing costs make them interesting for many applications in industries. The purpose of this study is to present a new method for calculating the flow through regenerative pumps with bucket form blades to predict the performance curves by a cheap and easy-to-use way.

Design/methodology/approach

The analysis was carried out based on the geometric shape of a fluid particle trajectory in a regenerative turbomachine. The fluid particle path was assumed to be a helix wrapped into a torus. Loss models were considered and the results of predictions were compared with computational fluid dynamics (CFD) data.

Findings

The overall trend of performance curves resulted from presented model looked consistent with CFD data. However, there were slight differences in high and low flow coefficients. The results showed that the predicted geometric shape of the flow path with the presented model (a helix wrapped into a torus) was not consistent with CFD results at high flow coefficients. Due to the complexity and turbulence of the fluid flow and errors in the calculation of losses, as well as slip factor, there was a discrepancy between the results of the presented model and numerical simulation, especially in high and low flow coefficients.

Originality/value

The analysis was carried out based on the geometric shape of a fluid particle trajectory in a regenerative turbomachine with bucket form blades. The fluid particle path was assumed to be a helix wrapped into a torus.

Citation

Nejadali, J. (2019), "Calculation of flow in incompressible regenerative turbo-machines with bucket form blades based on the geometry of flow path", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 29 No. 8, pp. 2606-2621. https://doi.org/10.1108/HFF-10-2018-0595