Meshing of Kaplan Turbines

Abstract

The purpose of this report is to explain all the processes carried out with various computer programs to support the development of a procedure to design hydraulic turbines of reaction type. The different parts of a real Kaplan Turbine were scanned and the data obtained were saved in several files which will be used as a starting point. These initial files are: hub.curve, shroud.curve, blade_profile.curve, guidevane.curve, and blade_1.stl, which will be mentioned within the report. The first task of the present thesis is to develop a good quality mesh of one blade of the turbine. To achieve that goal, the computer program used is Ansys TurboGrid, which is a powerful meshing tool that is specialized for Computer Fluid Dynamics analyses of turbomachinery bladerows. After practicing with some tutorials to gain experience with the program, a high quality mesh of the blade is successfully created. Then, the same process is followed in order to create a good mesh for a guide vane of the turbine. Once that both mesh files are created, the next step is to do simulations in CFX, although this is carried out in Xavier Vergés’s Thesis. The second objective of the project is to obtain the experimental curves of the shroud, hub and blade’s profile of the file blade_1.stl with the computer program ICEM, which is another Ansys software package used for CAD and mesh generation. The last aim of the thesis is to import the curves obtained in ICEM to BladeGen. BladeGen is a component of ANSYS BladeModeler which is useful to re-design existing blades or to create completely new blade designs. If the blade already exists, BladeGen facilitates the import of the blade’s geometry files. Therefore, the files created in ICEM will be exported to this computer program for further meshing and study.