1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
//Fluid Systems - By - Shiv Kumar
//Chapter 11- Centrifugal Pumps
//Example 11.14
//To Find (a)Vane Angle of Impeller at Inlet (b) Overall Efficiency of the Pump (c) Manometric Efficiency of the Pump.
clc
clear
//Given Data:-
Do=400; //Diameter of the Impeller at Outlet, mm
Di=200; //Diameter of the Impeller at Inlet, mm
N=1000; //Speed, rpm
Q=39; //Discharge, litres/s
Vfo=2.2; //Velocity of Flow, m/s
Vfi=Vfo;
Ds=150; //Diameter of Suction Pipe, mm
Dd=100; //Diameter of Delivery Pipe, mm
h_s=6; //Suction Head, m of water (abs)
h_d=30; //Delivery Head, m of water (abs)
P=15.75; //Power required to drive the pump, kW
beta_o=45; //Vane Angle at outlet, degrees
//Data Used:-
rho=1000; //Density of water, kg/m^3
g=9.81; //Acceleration due to gravity, m/s^2
//Computations:-
Do=Do/1000; //m
Di=Di/1000; //m
Ds=Ds/1000; //m
Dd=Dd/1000; //m
Q=Q/1000; //m^3/s
P=P*1000; //W
//(a)Vane Angle of Impeller at Inlet, beta_i
ui=%pi*Di*N/60; //m/s
beta_i=atand(Vfi/ui); //degrees
// (b) Overall Efficiency of the Pump
As=(%pi/4)*Ds^2; //m^2
Ad=(%pi/4)*Dd^2; //m^2
Vd=Q/Ad; //m/s
Vs=Q/As; //m/s
Hm=(h_d+Vd^2/(2*g))-(h_s+Vs^2/(2*g)); //m
eta_o=rho*Q*g*Hm/P*100; //In percentage
// (c) Manometric Efficiency of the Pump, eta_man
uo=%pi*Do*N/60; // Tangential velocity of Impeller at Outlet, m/s
Vwo=uo-Vfo/tand(beta_o); //m/s
eta_man=g*Hm/(Vwo*uo)*100; //In Percentage
//Results:-
printf(" (a)Vane Angle of Impeller at Inlet, beta_i=%.2f Degrees \n ",beta_i) //The answer vary due to round off error
printf(" (b) The Overall Efficiency of the Pump, eta_o =%.2f Percent \n ",eta_o) //The answer vary due to round off error
printf(" (c) Manometric Efficiency of the Pump, eta_man =%.2f Percent \n ",eta_man) //The answer vary due to round off error
|
