Chapter 5: Refrigeration and Air-Conditioning

Example 5.1, Page 178

In [2]:
#Variable declaration
t1=20;# in degree C
t2=5;# in degree C
T=t1-t2;
A=3000;# volume of air to be conditioned in m^3
Ht=1220;# in J

#Calculations
H1=A*Ht*T;
m=1000; # per m^3
Hl=2450*10**3;# latent heat in J/kg
w=5;# in kg
M=(w*A)/m;
H2=T*Hl;#in J
H=(H1+H2);
P=round(H/(3600*1000));

#Result
print "Power required,(kW) = %.f"%P

Power required,(kW) = 25

Example 5.2, Page 178

In [4]:
#Variable declaration
t1=25;# in degree C
t2=5;# in degree C

#Calculations
T=t1-t2;
A=6*5*4*(60./15);# volume of air to be conditioned in m^3/hour
Ht=1220;# in J
H1=A*Ht*T;
m=1000; # per m^3
Hl=836*10**3;# heat loss in J/C/h
H2=T*Hl;#in J/hour
H=(H1+H2);
Rh=round(H/(3600*1000));

#Result
print "Rating of heater,(kW) %.f "%Rh

Rating of heater,(kW) 8