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//Fluid Systems - By- Shiv Kumar
//Chapter 12- Reciprocating Pumps
//Example 12.7
//To Calculate (a)The Absolute Head in the Pump corresponding to the four corners of the cord and also the mid strokes (b)The Work done/minute.
clc
clear
//Given Data:-
D=125; //Bore of the Pump, mm
L=125; //Stroke length, mm
N=30; //Speed of Pump, rpm
H_s=3; //Suction Head, m
H_d=15; //Delivery Head, m
d_s=62.5; //Diameter of Suction Pipe, mm
d_d=d_s; //Diameter of Delivery Head
l_d=18; //Length of Delivery Pipe, m
l_s=l_d; //Length of Suction Pipe
f=0.032; //Co-efficient of friction for both Pipes
//Data Used:-
g=9.81; //Acceleration due to gravity, m/s^2
rho=1000; //Density of water, kg/m^3
H_a=10.2; //Atmospheric Pressure Head, m of water
//Computations:-
D=D/1000; //m
L=L/1000; //m
d_s=d_s/1000; //m
d_d=d_d/1000; //m
a=(%pi/4)*d_s^2; //m^2
A=(%pi/4)*D^2; //m^2
omega=2*%pi*N/60; //rad/s
r=L/2; //m
H_as=(l_s/g)*(A/a)*omega^2*r; //m
h_fs_max=f*(l_s/d_s)*(1/(2*g))*((A/a)*omega*r)^2; //m
//As Pipes are of same diameter and length,
H_ad=H_as;
h_fd_max=h_fs_max;
H_m=H_a-H_s-H_as; //Pressure Head at 'm' , m of water
H_r= H_a-H_s-h_fs_max ; //Pressure Head at 'r' , m of water
H_n=H_a-H_s+H_as ; //Pressure Head at 'n' , m of water
H_at_s= H_a+H_s+H_as ; //Pressure Head at 's' , m of water
H_o=H_a+H_d+h_fd_max ; //Pressure Head at 'o' , m of water
H_q=H_a+H_d+H_ad ; //Pressure Head at 'q' , m of water
m=rho*A*L*N*2/60; //mass of water/s, kg/s
Work_s=m*g*(H_s+H_d+(2/3)*h_fs_max+(2/3)*h_fd_max); //Word done/s, W
Work_m=Work_s*60; //Work done/min. , J/min
//Results:-
printf("Pressure Head at m =%.2f m of water\n ",H_m) //The answer vary due to round off error
printf("Pressure Head at r =%.3f m of water\n ",H_r) //The answer vary due to round off error
printf("Pressure Head at n =%.2f m of water\n ",H_n) //The answer provided in the textbook is wrong
printf("Pressure Head at s =%.2f m of water\n ",H_at_s ) //The answer provided in the textbook is wrong
printf("Pressure Head at o =%.3f m of water\n ",H_o) //The answer vary due to round off error
printf("Pressure Head at q =%.2f m of water\n\n ",H_q) //The answer provided in the textbook is wrong
printf("Work done/s=%.1f W \n Work done/minute=%.2f J/min. \n",Work_s,Work_m) //The answer provided in the textbook is wrong
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