# Chapter 3 : Kinematics of Fluid Flow¶

## Example 3.1 Page No : 78¶

In [1]:
import math

#Initialization of variables
Q = 0.5 	#cfs
d1 = 8. 	#in
d2 = 4.  	#in
R = 2.   	#in
h = 0.59 	#in

#calculations
Aa = math.pi*(d1/12)**2 /4
Va = Q/Aa
Ab = 2*math.pi*R*h/144
Vb = Q/Ab

#Results
print "Average velocity at section A  = %.2f fps "%(Va)
print " Average velocity at section B = %.2f fps "%(Vb)

# rounding off error
Average velocity at section A  = 1.43 fps
Average velocity at section B = 9.71 fps

## Example 3.2 Page No : 81¶

In [5]:
import math

#Initialization of variables
Q = 0.5 	#cfs
d1 = 8. 	#in
d2 = 4. 	#in
R = 2.   	#in
theta = 45.	#degrees

#calculations
h = (1-math.cos(math.radians(theta))) 	#Multiply by r
Aa = round(2*math.pi*h,2) 	#Multiply by r**2
V = Q/Aa 	#divide by r**2
aA = 0
r = 0.167 	#ft
V1 = V/r**2
dvbydx = round(V*2/r**3)
aB = V1*dvbydx

#Results
#The answer varies a bit from the text due to rounding off error
print "Acceleration at A  =  %d since flow is steady"%(aA)
print "Acceleration at B  =  %d ft/s**2"%(aB)

# rounding off error. please check.
Acceleration at A  =  0 since flow is steady
Acceleration at B  =  1140 ft/s**2