IAPWS = The International Association for the Properties of Water and Steam

make sure that you first install this library in your pc 

pip install iapws 

Some standard

here T = temperature (K) #all temperature are used herein Kelvin so you have to manually convert them as per your requirement

P = pressure (MPa) #all pressure units are available in this library are in Mega Pascal

h = enthalpy (kj/kg) #all enthalpy units are available in kj/kg

x = dryness fraction (unitless)

s = entropy kj/kgK

from iapws import IAPWS97 #1

T1 = 100+273  #2      100°C  converting into Kelving

a = IAPWS97(T =T1,x=.5) #3

P1 =  a.P #4

h = a.h #5

s1 = a.s #6

print('pressue',P1,'enthalpy',h,'entropy ',s1) #7

output : pressue 0.10087630072581115 enthalpy 1546.900746838229 entropy 4.3305976268584105

let's try to understand what is going on in the code

#1 basically we as are calling iapws and using iapws97 steam standard

#2  we are defining two points and with the help of this we will find out the other properties

make sure you use correct syntax here i have given temperature in K (kelvin) and x (dryness fraction)

so basically what i told to library that i have steam that is temperature 373K and at dryness fraction of 0.5

#4 to 7 now i simply  use a (where i store the two coordinates ) to find pressure ,enthalpy and entropy

what if you want to know specific volume of fluid and  specific volume of vapour ?

we know that at specific volume of fluid[vf] (x = 0) and at specific volume of vapour[vg] (x =1) for supersatured (x>1)

just put the value of x in the above parameter in code 

and type a.v

what is i don't put x = 0 and 1 .but put the value in between it

if you do that then specific volume that is given by this formla v = vf + x(vg - vf)


Now let's make it more complex

from iapws import IAPWS97

import numpy as np

from matplotlib.pyplot import*



T = np.linspace(300, 372+273, 200) # range of temperatures

for P in [0.1, 1, 2, 5, 10, 20]:

    steam = [IAPWS97(T=t, P=P) for t in T]

    S = [s.s for s in steam]

    plot(S, T, 'k-')#MPa

# saturated vapor and liquid entropy lines

svap = [s.s for s in [IAPWS97(T=t, x=1) for t in T]]

sliq = [s.s for s in [IAPWS97(T=t, x=0) for t in T]]

plot(svap, T, 'r-')

plot(sliq, T, 'b-')

xlabel('Entropy (kJ/(kg K)')

ylabel('Temperature (K)')


here we basically matplotlib.pyplot to use graph and various kind of loop

from code comment eveything is clear if you still have any doubts and query just comment i will try to help 

check out my video for more information

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