Chapter No 16 : Sizing Pneumatic systems

Example 16.1, Page No 422

In [13]:
#initialisation of variables
L=500        #ft length
d=47.2561    #diameter in
Q=650        # ft^3/min
T=40         #F  Temperature   

#CALCULATIONS
CR=(250+14.7)/14.7
Pf=(0.1025*L*(Q*1/60)*(Q*1/60))/(CR*d)

#RESULTS
print('The the pressure drop is = %.2f lbf/in^2' %Pf)

The the pressure drop is = 6.02 lbf/in^2

Example 16.2, Page No 423

In [9]:
#initialisation of variables
L=(8*5.2)+(2*59)+(1*10.3)       #ft length
C=0.1025         # Experimental coefficient
d=47.2561        # internal diameter
Q=500.0          # ft^3/min free air   
CR=4.4           # ratio of compression of pipe


#CALCULATIONS

Pf=(C*L*((Q*1/60)*(Q*1/60)))/(CR*d)

#RESULTS
print('The the pressure drop is = %.2f lbf/in^2' %Pf)

The the pressure drop is = 5.82 lbf/in^2

Example 16.3, Page No 433

In [2]:
#initialisation of variables
#CALCULATIONS
T=60+(0.25*60)   #total air consumption ft^3/min

#RESULTS
print('The total air consumption = %.2f ft^3/min' %T)

The total air consumption = 75.00 ft^3/min

Example 16.4, Page No 434

In [3]:
#initialisation of variables
Qr=10       #ft^3/min consumption rate
t=5         #time min
p1=125      #lbf/in^2 pressure
p2=100      #lbf/in^2 pressure

#CALCULATIONS
Vr=(14.7*Q*t)/(p1-p2)

#RESULTS
print('The size of the receiver = %.2f ft^3' %Vr)

The size of the receiver = 29.40 ft^3

Example 16.5, Page No 444

In [4]:
import math


#initialisation of variables
Q=35          #ft^3/min consumption rate
t=540         #time min
p1=90+14.7    #presure lbf/in^2
p2=80+14.7    # pressure lbf/in^2

#CALCULATIONS
K=(p1+p2)/2
Cv=(Q/22.67)*(math.sqrt(t/((p1-p2)*K)))

#RESULTS
print('The size of the air valve = %.2f ' %Cv)

The size of the air valve = 1.14

Example 16.7, Page No 448

In [2]:
import math


#initialisation of variables
Q=35          #ft^3/min consumption rate
V1=0.327      #volume  ft^3/min
p1=104.7      #presure lbf/in^2
p2=14.7       #pressure lbf/in^2
d=3          #in diameter
#CALCULATIONS
A=(3.14*(d*d)/4
Q=((A*4)/1728)*20
V2=p1*V1/p2

#RESULTS
print('The free air consumption = %.2f ft^3/min' %V2)

The free air consumption = 2.33 ft^3/min

Example 16.8, Page No 451

In [2]:
import math


#initialisation of variables
Fa=0.065        # free air ft^3/in
d=4             # stroke in
c=20            # cycle rate cycles/min
#CALCULATIONS
Qv=(Fa*d*c)/2

#RESULTS
print('The free air consumption = %.2f ft^3/min' %Qv)

The free air consumption = 2.60 ft^3/min