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
|
//Fluid Systems - By - Shiv Kumar
//Chapter 11- Centrifugal Pumps
//Example 11.18
//To Find (a)Manometric Efficiency. (b)Inlet Vane Angles. (c)Loss of Head at Inlet of Impeller
clc
clear
//Given Data:-
Q=0.21; //Discharge, m^3/s
Af=0.085; //Cross-sectional Area of Flow, m^2
Di=300; //Inner Diameter of the Impeller, mm
Do=600; //Outer Diameter of the Impeller, mm
N=600; //Speed, rpm
Hm=19; //Manometric Head, m
beta_o=35; //degrees
Q_per=30; //Percentage by which Discharge is reduced
//Data Used: -
g=9.81; //Acceleration due to gravity, m/s^2
//Computations:-
Di=Di/1000; //m
Do=Do/1000; //m
ui=%pi*Di*N/60; //Tangential Velocity of Impeller at Inlet, m/s
uo=%pi*Do*N/60; //Tangential Velocity of Impeller at Outlet, m/s
Vfo=Q/Af; //Velocity of Flow, m/s
Vfi= Vfo;
Vwo=uo-Vfo/tand(beta_o); //m/s
//(a)Manometric Efficiency, eta_man
eta_man=g*Hm/(Vwo*uo)*100; //In Percentage
//(b)Inlet Vane Angle, beta_i
beta_i=atand(Vfi/ui); //degrees
//(c)Loss of Head at inlet, H_L
Q_dash=Q-Q_per/100*Q; //m^3/s
Vfi_dash=Q_dash/Af; //m/s
H_L=(ui-Vfi_dash*cotd(beta_i) )^2/(2*g); // m of water
//Results
printf("(a)Manometric Efficiency, eta_man =%.2f Percent \n",eta_man) //The answer vary due to round off error
printf ("(b)Inlet Vane Angle, beta_i =%.2f Degrees \n",beta_i) //The answer vary due to round off error
printf ("(c)Loss of Head at Inlet to the Impeller =%.3f m of water", H_L) //The answer vary due to round off error
|
