assignment1_step1_micev.py

#Assignment 1 - Step 1

#Rate of transfer heat through composite wall (values are taken from Example D) 

#dimenssions of wall that is considered
Height_of_wall=3 #height of wall in [m]
Width_of_wall=5 #width of wall in [m] 

#dimenssions of bricks that are used 
H=22 #height of brick in [cm]
d=16 #depth of brick in [cm] 

#thermal conductivity of brick
kb=0.72 # average thermal conductivity of brick [W/m*degree C] 

#plastic layers
tp=3 #thickness of plastic layers that separates 2 bricks in [cm] 
tp_side=2 #thickness of plastic layers on each side of the brick in [cm] 
kp=0.22 #average thermal conductivity of plastic [W/m*degree C] 

#foam 
tf=3 #thickness of foam layer on the inner side of the wall in [cm] 
kf=0.026 #average thermal conductivity of foam [W/m*degree C] 

#temperatures
T1=20 #indoor temperature in [degree C]  
T2=-10 #outdoor temperature in [degree C] 

#convection heat transfer coefficients of outer and inner surface 
h1=10 #conv. heat transfer coefficient on inner surface of the wall in [W/m2 degree C] 
h2=25 #conv. heat transfer coefficient on outer surface of the wall in [W/m2 degree C] 

#For calculating values of resistances, the width of the wall is considered to be 1 m (Unit area)
#calculation of resistances 
height=float(H+tp)  
Ri=100/(h1*height*1) 
Rfoam=tf/(kf*height*1) #there is no need for conversition in m because height and tf are given in cm
Rpside=tp_side/(kp*height*1)
Rpcenter=(2*d)/(kp*tp*1) #2*d because A=tp/2 [m2]
Rb=d/(kb*H)
Ro=100/(h2*height)

#calculation of total resistance
Req=((Rpcenter**2)*Rb)/(Rpcenter**2+2*Rb*Rpcenter) #resistance of three layers that are paralel
Rtot=Ri+Rfoam+Rpside+Req+Rpside+Ro
print(" Total thermal resistance of a composite wall is "+str(Rtot)+ " [degree C/W] ")

#calculation of rate of heat transfer through the one unit of composite wall
Qunit=(T1-T2)/Rtot
print(" The rate of heat transfer through one unit of composite wall is "+str(Qunit)+" W")

#calculation of rate of heat transfer through the composite wall
proportion=(Height_of_wall*Width_of_wall)*100/height
Q=Qunit*proportion
print(" The rate of heat transfer through the entire wall is "+ str(Q) + " W")