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//Fluid Systems - By Shiv Kumar
//Chapter 12- Reciprocating Pumps
//Example 12.5
//To Determine the Pressure Head on Piston at Begining, Middle and End of Suction Stroke.
clc
clear
//Given Data:-
L=150; //Length of Stroke, mm
l_s=7; //Length of Suction Pipe, m
ds_by_D=3/4; //Ratio of Suction Pipe Diameter to Piston Diameter, ds/D
hs=2.5; //Suction Head, m
ds=75; //Diameter of Suction Pipe, mm
N=75; //Crank Speed, rpm
f=0.01; //Co-efficient of Friction
//Data Used:-
g=9.81; //Acceleration due to gravity, m/s^2
h_atm=10.33; //Atmospheric Pressure Head, m of water
//Computations:-
L=L/1000; //m
ds=ds/1000; //m
r=L/2; //Crank radius, m
A_by_as=(1/ds_by_D)^2;
omega=2*%pi*N/60; //Angular Velocity, rad/s
//At Begining of Suction Stroke,
theta=0; //degrees
h_as=(l_s/g)*A_by_as*omega^2*r*cosd(theta); //Acceleration Head, m of water
h_fs=(4*f*l_s/(2*g*ds))*(A_by_as*omega*r*sind(theta))^2; //Head loss due to friction, m of water
h_v=hs+h_fs+h_as; //Pressure Head on Piston, m of water Vaccum
h_abs=h_atm-h_v; //Pressure Head on Piston, m of water Absolute
//Result 1
printf("At Begining of Suction Stroke\n Pressure Head on Piston=%.2f m of water Vaccum \n\t\t\t =%.2f m of water Absolute\n\n",h_v,h_abs) //The answer vary due to round off error
//At Mid of Suction Stroke,
theta=90; //degrees
h_as=(l_s/g)*A_by_as*omega^2*r*cosd(theta); //Acceleration Head, m of water
h_fs=(4*f*l_s/(2*g*ds))*(A_by_as*omega*r*sind(theta))^2; //Head loss due to friction, m of water
h_v=hs+h_fs+h_as; //Pressure Head on Piston, m of water Vaccum
h_abs=h_atm-h_v; //Pressure Head on Piston, m of water Absolute
//Result 2
printf("At Middle of Suction Stroke\n Pressure Head on Piston=%.4f m of water Vaccum \n\t\t\t =%.3f m of water Absolute\n\n",h_v,h_abs) //The answer vary due to round off error
//At End of Suction Stroke,
theta=180; //degrees
h_as=(l_s/g)*A_by_as*omega^2*r*cosd(theta); //Acceleration Head, m of water
h_fs=(4*f*l_s/(2*g*ds))*(A_by_as*omega*r*sind(theta))^2; //Head loss due to friction, m of water
h_v=hs+h_fs+h_as; //Pressure Head on Piston, m of water Vaccum
h_abs=h_atm-h_v; //Pressure Head on Piston, m of water Absolute
//Result 3
printf("At End of Suction Stroke\n Pressure Head on Piston=%.2f m of water Vaccum \n\t\t\t =%.2f m of water Absolute\n\n",h_v,h_abs) //The answer vary due to round off error
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