EXPERIMENTAL ANALYSIS ON FRANCIS TURBINE AT FULL LOAD TO DETERMINE THE PERFORMANCE CHARACTERISTICS CURVES

Turbines are machines that convert Kinetic energy of fluids (e.g, water, steam, air, etc) into mechanical energy by causing a bladed rotor to rotate. The turbines are designed for a particular value of speed, head, efficiency, power or discharge. But operation of turbines under similar conditions do not yield a new concept. So, it is necessary to operate turbine under new conditions from these they have been designed. Here test is conducted on Francis turbine to know their dead-on behavior under varying conditions in Fluid Mechanics and Hydraulics Machines Laboratory. The results obtained were graphically plotted and the curves obtained are known as Constant head or Constant speed characteristics curve. The results obtained are the outcome of precise measurement and careful observation. This paper focuses mainly on the experimental analysis to get actual performance characteristics curves. The entire experimentation is carried out in the Fluid Mechanics and Hydraulics Laboratory. Head and gate opening are maintained constant. The speed is fluctuated by permitting a varying quantity of water to flow through the inlet openings. The Brake Horse Power is measured automatically by eddy dynamometer. After the completion of the experiment, a curve is plotted between unit discharge and unit speed for Francis turbine. The curves between unit discharge and unit speed are rising curves. The discharge increases with the increase in speed. Finally the overall efficiency of turbine was calculated along with percentage of full load.