Design and Analysis of Runner Blade Actuation Mechanism for Horizontal Kaplan Turbine

Abstract

Kaplan Turbine is a type of hydraulic turbine using of low head applications. Horizontal Tubular “s” type turbine is a horizontal type of Kaplan turbine, which having automatic control for adjustment of both runner blade and guide vanes.

The mechanism using to adjust the position of runner blade, according to load variation is known as the Runner Blade Actuation Mechanism. It is necessary to design proper actuation mechanism by considering both point of high performance and easy maintenance. Also it should be economical.

In this thesis, runner blade actuation mechanism is designed by considering the actual opearion parameter of the Turbine. From the given data of turbine, the main characteristics of turbine like power, specific speed, runaway speed, critical speed, runner Diameter, and hub diameters etc… are determined. From this main characteristics the hydraulic moment, force acting on runner blade, required oil pressure to operate the mechanism are calculated.

As a part of the design of actuation mechanism, the different components of the mechanism are designed against the actual site operational parameters. All this components are models in Pro/E soft ware and checked the strength through FEM code of Ansys Workbench. Stress and deformation values of all the components are well within the acceptable limits prescribed by the standards, hence the design is safe.