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//Fluid system - By - Shiv Kumar
//Chapter 2 - Impact of Jet
//Example 2.35
clc
clear
//Given Data:-
Vr=14; //Relative Velocity of ship, m/s
a=0.025; //cross-sectional area of Jet, m^2
u=32; //Speed of ship, km/hr
eta_P=80/100; //Efficiency of pump
h_f=2.5; //Frictional Losses, m of water
//Data Used:-
rho=1000; //Density of water, kg/m^3
g=9.81; //Acceleration due to gravity, m/s^2
//Computations:-
u=u*1000/3600; //m/s
//(i)
//(a)
V=Vr-u; //m/s
F=rho*V*a*(V+u); //N
//(b)
W=F*u; //N-m/s, Value in textbook is wrong due to incorrect value of u ia used.
//(ii)
E=rho*a*Vr*((Vr^2-u^2)/2+g*h_f); //Actual energy supplied to water per second, N-m/s
OE_P=E; //Output fluid energy per second of pump
//(a)
P=OE_P/eta_P; //Power required to drive the pump, W
//(b)
eta_o=W/P*100; //In percentage
//Results:-
printf("(i) (a)Resistance to the motion of ship, F=%.f N \n", F) //The answer provided in the textbook is wrong
printf(" (b)Propulsive work per second=%.2f N-m/s \n\n", W) //The answer provided in the textbook is wrong
printf("(ii) (a)Power required to drive the pump=%.2f W \n", P) //The answer provided in the textbook is wrong
printf(" (b)Overall Efficiency of propulsion, eta_o=%.2f percent", eta_o) //The answer vary due to round off error
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