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//Fluid System By Shiv Kumar
//Chapter 6 - Kaplan and Propeller Turbines
//Example 6.5
//To Find (a)Guide Vane Angle at Inlet (b)Runner Vane Angle at Inlet
clc
clear
//Given:
P=22500 //Shaft Power, KW
H=20; //Head, m
N=148; //Speed, rpm
eta_H=95/100; //Hydraulic Efficiency
eta_o=89/100; //Overall Efficiency
D=4.5; //Diameter of Runner, m
d=2; //Diameter of Hub, m
Beta_o=34 //Runner Vane Angle at Outlet, Degrees
//Data Required:
rho=1000; //Density of Water, Kg/m^3
g=9.81; //Acceleration due to gravity, m/s^2
//Computations
u=%pi*D*N/60; //Velocity of runner, m/s
Q=P*10^3/(rho*g*H*eta_o); //Discharge, m^3/s
Vfi=Q/((%pi/4)*(D^2-d^2)); // m/s
//As Velocity of Flow is Constant
ui=u;
uo=u;
Vfo=Vfi;
Vf=Vfo;
Vrwo=Vfo/tand(Beta_o); //m/s
Vwo=uo-Vrwo;
Vo=sqrt(Vfo^2+Vwo^2); //m/s
Vwi=(g*H-Vo^2/2)/u+Vwo ; //m/s
//(a)Guide Vane Angle at Inlet,Alpha_i
Alpha_i=atand(Vfi/Vwi); //Degrees
//(b)Runner Vane Angle at Inlet,Beta_i
Beta_i=180-atand(Vfi/(ui-Vwi)); //Degrees
//Results
printf("(a)Guide Vane Angle at Inlet, Alpha_i=%.2f Degrees\n",Alpha_i) //The answer vary due to round off error
printf("(b)Runner Vane Angle at Inlet, Beta_i =%.f Degrees\n",Beta_i) //The answer provided in the textbook is wrong
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