KAJI EKSPERIMENTAL PENGARUH VARIASI DIAMETER NOZZLE DAN DIAMETER RUNNER TERHADAP DAYA DAN EFISIENSI MODEL TURBIN PLETON

Abstract

Pelton turbine is one type of impulse turbine, type of water turbine which works to change the available whole energy of water such as pressure, potential, and speed into kinetic energy to rotate turbines. Runner which consist of a number of blades is the main component on Pelton turbine when the turbine rotates because the force of water at high speed out of nozzle. Impulse reactions occur because the water jets hit the blades causing torque of turbine shaft causing runner will continue rotates for object hit the blades. Experimental assessment was conducted to investigate effect of nozzle diameter variations as a media to transmit water and runner diameter variations as the main media for generating mechanical energy in power and efficiency of the Pelton Turbine models in Fluid Laboratorium August 17, 1945 University of Surabaya as a prototype model of Micro Hydro Power Plant ( MHPP ). Stages of research was done by designing and planning some variation of the nozzle diameter and runner diameter with reference using head and flow capacity of available water pump. Specified parameters and variables used for experimental assessment is single nozzle with diameter 0,006 m and 0,009 m and runner with diameter 0,15 m, 0,17 m and 0,19 m. Blades used half cylinder shape with the specifications, width 0,036 m, length 0,027 m, depth 0,00081 m, blade gap width 0,001 m, and the distance of center water emmision to blade tip 0,00135 m. From the test results, variations of nozzle with diameter 0,006 m and runner with diameter 0,15 m produces the largest turbine power 49,53 watt, the best turbine efficiency of 87,97%, and the largest generator power 10,56 watt. Meanwhile, the variation nozzle with diameter of 0,009 m and runner with diameter 0,15 m, generating the best generator efficiency 52.43%. From the characteristics graph of Pelton turbines, found same trend with the theory that the efficiency of the turbine decreasing after reaching the maximum efficiency speed ratio of 0,46 and higher turbine efficiency directly proportional to turbine power produced. Keyword : Pelton Turbine, Nozzle, Runner, Power, Efficiency