In this work, we seek to predict the characteristic curve of a commercial centrifugal radial flow pump operating as a turbine, applying a novel methodology based on the state of the art. Initially, the characteristic curve in pump mode is validated through numerical simulations. The results obtained are approximate to the points awarded by the manufacturer, with an error of less than 7% at the best efficiency point. Subsequently, the characteristic curve is generated in turbine mode, obtaining an error of less than 10% respect to mathematical model. Then, velocity and pressure contours are evaluated to validate the fluid dynamic behavior. Finally, the site operating conditions for electricity generation are obtained. With this, it is proposing a methodology for the selection of these turbomachines, applying an economic technology for zones that do not have access to the electrical energy, since it was not found a method that is being applied for its correct election in the hydroelectric generation at low scale.

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.

This article presents a mathematical model to calculate the cost and production of electrical energy of a system that combines energy storage through renewable sources such as wind and solar energy, applying a theoretical framework of mathematical aspects to evaluate a pumped storage system with Pelton turbines, using a novel methodology, easy to replicate. The results show that a greater increase in the diameter in the pipe of the pumping equipment reduces the electrical power supplied to the pump. On the other hand, the hydraulic losses in the pipe leading to the Pelton turbine are negligible for long lengths, so setting the maximum length instead of a variable-length with the hydraulic height does not affect the result. Finally, the information and explanation of each of the graphs that correlate to the variables of interest are shown. This seeks to offer a contribution to support technological development in areas that do not have electricity, taking advantage of natural resources.