Similarity Laws for Turbine Specific Speed and Cavitations

It is possible that a hydraulic machine will not give the desired result for which it has been designed. Such a machine is costly for manufacture and once it is made, it is difficult to change its components. Therefore, it is required to predict the performance of a prototype hydraulic machine before it is manufactured. This is done by making its model. Experiments are first performed on models from their results the performance of the prototype machine is predicted chapter on "Dimensional and Model Analysis" given in Fluid Mechanics will be useful for the prototype. Here prototype and its model are two similar machines having different specifications, which are to be compared. The concept of "Unit and specific Quantities" is a prerequisite for comparison of hydraulic machines. In addition, in this chapter a brief discussion about cavitation in turbine, turbine section, marking types of turbine and hydraulic turbine classification and section according to hydraulic power plants.

Keywords: Cavitation in turbines, Similarity laws, Turbines classification and selection.