Chapter 12 : Fluid Measurements

Example 12.1 Page No : 417

In [1]:
import math 
	
#Initialization of variables
P1 = 10. 	#psia
Q = 0.6 	#cfs
A1 = 0.0491 #ft**2
g = 32.2
V = 39.2	#fps
A0 = 0.0218 #ft**2
d1 = 2. 	#in
d2 = 3. 	#in
	
#calculations
Phead = P1*144/62.4
V1 = Q/A1
V2i =  math.sqrt(2*g*(Phead + V1**2 /(2*g)))
Cv = V/V2i
A2 = Q/V
Cc = A2/A0
Cd = Cc*Cv
hL = (1/Cv**2 -1)*(1- (d1/d2)**4)*V**2 /(2*g)
	
#Results
print " Cc  =  %.2f "%(Cc)
print " Cd =  %.2f"%(Cd)
print " Cv =  %.2f"%(Cv)
print " Head loss  =  %.2f ft"%(hL)

 Cc  =  0.70 
 Cd =  0.68
 Cv =  0.97
 Head loss  =  1.23 ft

Example 12.2 Page No : 425

In [2]:
import math 
	
#Initialization of variables
d = 2.  	#in
g = 32.2
d1 = 3. 	#in
k = 1.06
	
#calculations
A2 = math.pi/4 *d**2 /144
dp = d/12
Q = k*A2*math.sqrt(2*g*dp)
A = math.pi/4 *(d1/12)**2
V1 = Q/A
K2 = 1.04
Q2 = K2/k *Q
	
#Results
print "Flow rate  =  %.4f cfs"%(Q2)

Flow rate  =  0.0743 cfs

Example 12.3 Page No : 428

In [3]:
import math 
	
#Initialization of variables
P1 = 700. 	#kN/m**2
P2 = 400. 	#kN/m**2
D2 = 12.5 	#cm
D1 = 25. 	#cm
C = 0.985
g = 9.81
R = 287. 	#m**2/s**2 K
T = 273.+20 	#K
	
#calculations
Pr = P2/P1
Dr = D2/D1
Y = 0.72
gam1 = P1*g/(R*T)
G = C*Y*math.pi/4 *(D2/100)**2 *math.sqrt(2*g*gam1*(P1-P2)/(1- Dr**4))
	
#Results
print "Weight flow rate  =  %.4f kN/s"%(G)

Weight flow rate  =  0.1971 kN/s

Example 12.4 Page No : 432

In [4]:
import math 
	
#Initialization of variables
V = 3. 	#fps
y = 1. 	#ft
L = 4. 	#ft
	
#calculations
H =  (V*y/3.33)**(2./3)
P = L-H
	
#Results
print "Height of weir  =  %.2f ft"%(P)

Height of weir  =  3.07 ft