Characterization of a Commercial Axial Flow PAT Through a Structured Methodology Step-by-Step

Abstract

A centrifugal pump as a turbine (PAT) is the inverse operation of a conventional pump, which takes advantage of the hydraulic energy of water to convert it into rotational mechanical energy and subsequently into electrical energy, through a generator. The CFD analysis allows predicting the fluid dynamic behavior and calculating the operating characteristic curve of the PAT, thus reducing costs in experimental setups. In the literature, the operation of the turbomachine in pump and turbine mode is evidenced. However, there is no methodology applied in commercial axial flow pumps that exposes a structured step-by-step to carry out the numerical and fluid dynamic analysis. In this study, a novel structured methodology is developed describing the numerical and CFD analysis of a commercial axial flow centrifugal pump, which allows validating the characteristic curve in pump mode and then obtaining the site conditions in turbine mode, for its application in small hydroelectric power plants. As a result, in pump mode, an error of less than 8% is obtained between the manufacturer's curve and the numerical curve. In turbine mode, the best performance is around 73%. The aim is to propose a replicable algorithm in future works that allows the proper analysis in commercial axial flow pumps.