Session: 15-01-01: ASME International Undergraduate Research and Design Exposition

Paper Number: 99133

99133 - Computational Fluid Dynamics Analysis of Kaplan Turbines in Nominal Operating Conditions at the Yacyretá Hydropower Plant, a Case Study 

The Yacyretá Hydropower Plant (CHY) is located at the border between Paraguay and Argentina, and is powered by the Paraná River, one of the most mighty rivers when it comes to water flow volume. The CHY uses  Kaplan turbines with a vertical shaft coupled directly to an electric generator for an average gross generation of 15,000,000 MWh of electric energy. 

The importance of this hydropower plant for the economy of the previously mentioned countries is immense, given that the power produced at the plant supplies electric power to major industrial, business and commercial customers in both countries. This is the main reason as to why this study was conducted.
The research department of a local university was approached by the CHY for the computational analysis. A Computational Fluid Dynamics (CFD) analysis is performed by undergraduate students from local university for this  purpose. The CHY mechanical design technicians measured the actual turbine in order to design and provide the Computer Aided Design (CAD) model of the actual Kaplan Turbine, which is used in this analysis. Simulations were performed on standard desktop computers at the university in charge of the research study, by Mechanical Engineering undergraduate students, who are currently taking an advanced fluid mechanics course. The simulation software employed was licensed to the university for academic and research purposes. As opposed to previous similar studies, which employed multiphysics-based softwares, this study was performed using a mono physics-based software, given that its simplicity was favorable for the researching students.

The simulation was set to perform at nominal operating conditions of the CHY, since the previously mentioned situation is the most representative in terms of parameters such as water net head, volume flow and blade angle orientation. It is important to mention that the following analysis is focused on the effect of the fluid on the turbine blade surfaces. A rotating mesh at blade zones was implemented for that. 

The simulation results showed detailed pressure distribution and fluid flow velocities that affect the turbine blade surfaces, and therefore, the efficiency of the CHY. This work gave the local CHY engineers an additional tool to assess operating conditions before their implementation, and also, to compare them to real-life operation. Fluid pressure distribution on blade surfaces provided important information on potential fluid cavitation. In addition, torque data during turbine operation was obtained. These results are very critical to evaluate turbine performance and compare them to the turbine prototype collinear hill curves shared by the hydraulic machine manufacturer. 

Presenting Author: Elias Espínola Facultad de Ingeniería - Universidad Nacional de Asunción

Presenting Author Biography: Elías Espínola is a fifth-year mechanical engineering student at the Faculty of Engineering of the National University of Asunción. He is interested in aerospace engineering, fluid mechanics, and electric vehicles. He aspires to get a master's degree in one of these branches to work for one of these sectors. He is currently the chair of the ASME Student Section at the National University of Asunción.

Authors:

Vivian Gonzalez Facultad de Ingeniería - Universidad Nacional de Asunción
Liz Esquivel Facultad de Ingeniería - Universidad Nacional de Asunción
Elias Espínola Facultad de Ingeniería - Universidad Nacional de Asunción
Fernando Arenas Facultad de Ingeniería - Universidad Nacional de Asunción
Jovan Toews Facultad de Ingeniería - Universidad Nacional de Asunción
Patrik Kehler Facultad de Ingeniería - Universidad Nacional de Asunción
Jorge Kurita Facultad de Ingeniería - Universidad Nacional de Asunción