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//Fluid Systems - By - Shiv Kumar
//Chapter 4 - Pelton Turbine (Impulse Turbine)
//Example 4.14
clc
clear
//Given Data:-
H=452; //Net Head, m
m=12; //Jet Ratio (D/d)
Ku=0.46; //Speed Ratio
AoD=165; //Angle of Jet Deflection, degrees
Cv=0.98; //Co-efficient of Velocity
Loss_f=15; //Percentage of Friction Loss of Buckets
eta_o=86/100; //Overall Efficiency
P_G=10200; //Power developed by Generator, HP
eta_G=95/100; //Generator Efficiency
//Data Used:-
rho=1000; //Density of water, kg/m^3
g=9.81; //Acceleration due to gravity, m/s^2
//Computations:-
P_G=P_G*736; //W
Vro_by_Vri=1-Loss_f/100; //Vro/Vri
beta_o=180-AoD; //degrees
u=Ku*sqrt(2*g*H); //Velocity of Runner, m/s
ui=u;
uo=u;
Vi=Cv*sqrt(2*g*H); //m/s
Vwi=Vi;
Vri=Vi-ui; //m/s
Vro=Vri*Vro_by_Vri; //m/s
Vrwo=Vro*cosd(beta_o); //m/s
Vwo=uo-Vrwo; //m/s
P=P_G/eta_G; //Shaft Power, W
Q=P/(rho*g*H*eta_o); //Discharge, m^3/s
//(a)
d=sqrt(Q/((%pi/4)*Vi)); //Diameter of Jet, m
//(b)
D=m*d; //Diameter of Runner, m
//(c)
Pr=rho*Q*(Vwi-Vwo)*u/1000; // Power developed by Runner, kW
//(d)
eta_m=P/(Pr*1000)*100; //Mechanical Efficiency in Percentage
//Results:-
printf("(a) Diameter of the Jet, d=%.3f m\n",d)
printf(" (b)Diameter of the Runner, D=%.3f m\n",D) //The answer vary due to round off error
printf(" (c)Power Developed by the Runner=%.3f kW\n",Pr) //The answer provided in the textbook is wrong
printf(" (d)Mechanical Efficiency , eta_m=%.2f Percent\n",eta_m) //The answer vary due to round off error
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