# Chapter 7 : Flow Through Packed Beds¶

### example 7.1 page no : 136¶

In :
import math

# Initialization of Variable
mu = 1.83/1000
rhom = 1.355*10000              #density mercury
K = 5.
g = 9.81
d = 2.5/100
pi = 3.14
thik = 2.73/100
rho = 3100.                     #density of particles
Q = 250./(12.*60+54)/10.**6

#calculation
A = pi*d**2./4.
Vb = A*thik                     #volume of bed
Vp = 25.4/rho/1000              #volume of particles
e = 1-Vp/Vb
u = Q/A
delP = 12.5/100*rhom*g
S = math.sqrt(e**3*delP/K/u/thik/mu/(1-e)**2)
S = round(S/1000)*1000.
d = 6./S
print "average particle diameter in (x10**-6m) %.4f"%(d*10**6)
A = pi*d**2./1000/(4./3*pi*d**3/8*rho)
print "surface area per gram of cement (cm**2): %.4f"%(A*10**4)

average particle diameter in (x10**-6m) 47.6190
surface area per gram of cement (cm**2): 406.4516


### example 7.2 page no : 138¶

In :
import math

# Initialization of Variable
mu = 2.5/1000
rho = 897.
g = 9.81
pi = 3.1414
K = 5.1
l = 6.35/1000
d = l
hei = 24.5+0.65
len = 24.5
dc = 2.65                           #dia of column
thik = 0.76/1000
Vs = pi*d**2/4*l-pi*l/4*(d-2*thik)**2           #volume of each ring
n = 3.023*10**6
e = 1-Vs*n
e = round(e*1000)/1000.
Surfacearea = pi*d*l+2*pi*d**2/4+pi*(d-2*thik)*l-2*pi*(d-2*thik)**2/4
S = Surfacearea/Vs
S = round(S)
delP = hei*g*rho
delP = round(delP/100.)*100.
u = e**3*delP/K/S**2/mu/(1-e)**2/len
Q = pi*dc**2/4*u
print "initial volumetric flow rate in (m**3/s): %.4f"%Q

initial volumetric flow rate in (m**3/s): 2.8271


### example 7.3 page no : 140¶

In :
import math

# Initialization of Variable
dr = 2.                     #dia of column
mu = 2.02/10**5
rho = 998.
K = 5.1
g = 9.81
Q = 10000./3600
l = 50.8/1000
d = l
n = 5790.
len = 18.
thik = 6.35/1000
pi = 3.1414

#part1
#calculation

CA = pi*dr**2./4            #cross sectional area
u = Q/CA
Vs = pi*d**2/4*l-pi*l/4*(d-2*thik)**2       #volume of each ring
e = 1-Vs*n
Surfacearea = pi*d*l+2*pi*d**2/4+pi*(d-2*thik)*l-2*pi*(d-2*thik)**2/4
S = Surfacearea/Vs
S = round(S*10)/10.
delP = K*S**2/e**3*mu*len*u*(1-e)**2
delh = delP/rho/g
print "pressure drop in terms of (cm of H20) %.4f"%(delh*100)

pressure drop in terms of (cm of H20) 0.3540

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