Ejemplo 2

 

En esta entrada aplicaremos las correlaciones de la entrada anterior comenzando por la de Mattar, L., Brar,G.S. y Aziz, K.

import math as math

import numpy as np

 # Mattar, L., Brar,G.S. y Aziz, K.

 

A1 = 0.31506237

A2 = -1.0467099

A3 = -0.57832729

A4 = 0.53530771

A5 = -0.61232032

A6 = -0.10488813

A7 = 0.68157001

A8 = 0.68446549

 

z = 0.78970

Pr = 1.41826

Tpr = 1.35

Ppr = 5.60

 

Delta  = A1+(A2/Tpr)+(A3/(Tpr**3))+2*(A4+(A5/Tpr))*Pr+5*A5*A6*(Pr**4/Tpr)+((2*A7*Pr)/(Tpr**3))*(1+(A8*Pr**2)-(A8*Pr**2)**2)*math.exp(-A8*Pr**2)

 

Cr = (1/Ppr)-(0.27/((z**2)*Tpr))*(Delta/(1+(Pr/z)*Delta))

 

Cg1 = Cr/680

 

# Sarem, A.M.

 

X = -0.257

Y = -0.684

 

MM = np.array([[2.1434,0.0832,-0.0215,-0.0009,0.0043,-0.0017],[0.3313,-0.1340,0.0669,-0.0272,0.0089,-0.0022],[0.1057,-0.0504,0.0051,0.0106,-0.0073,0.0027],[0.0522,0.0443,-0.0193,0.0059,0.0015,-0.0028],[0.0197,-0.0264,0.0193,-0.0115,0.0043,-0.0081],[0.0053,0.0089,-0.0109,0.0096,-0.0060,0.0031]])

 

 

PX0 = np.array([[0],[0.16551],[0.641002*X],[0.379221*(5*(X**2)-1)],[0.716652*(7*(X**3)-3*X)],[0.594225*(21*(X**4)-14*(X**2)+1)]])

PY0 = np.array([[0.7071068],[1.224745*Y ],[0.7905695*(3*(Y**2)-1)],[0.9354145*(5*(Y**3)-3*Y)],[0.265165*(35*(Y**4)-30*(Y**2)+3)],[0.293151*(63*(Y**5)-70*(Y**3)+15*Y)]])

 

Delta = 0

 

for i in np.arange(0,6):

            for j in np.arange(0,6):

 

                        Delta = Delta+MM[i][j]*PX0[i]*PY0[j]

 

Cr = (1/Ppr)-(Delta/z)

 

Cg2 = Cr/680

 

# Papay, J.

 

Delta = -(3.52/(10**(0.9812*Tpr)))+((0.548*Ppr)/(10**(0.8157*Tpr)))

 

Cr = (1/Ppr)-(Delta/z)

 

Cg3 = Cr/680

 

# Hall, K.R. y Yarborough, L.

 

t = 485/(194+460)# Tpc/T

 

def DDF(Y,t):

 

            A = 0.06125*t*np.exp(-1.2*(1-t)**2)

            B = (14.76*t-9.76*t**2+4.58*t**3)

            C = (90.7*t-242.2*t**2+42.4*t**3)

            D = 2.18+2.82*t

            Y = -A*Ppr+((Y+(Y**2)+(Y**3)-(Y**4))/((1-Y)**3))-B*(Y**2)+C*(Y**D)

 

            return Y

 

Y = 0.01

conteo = 0

error = 1

 

while error > 0.00000001:

 

            dy = ((DDF(Y,t)+0.0001)-DDF(Y,t))/0.0001

            yn = Y-DDF(Y,t)/dy

 

            conteo = conteo + 1

 

            error = (yn-Y)/yn

 

            Y = yn

 

A = 0.06125*t*math.exp(-1.2*(1-t)**2)

B = 14.76*t-9.76*t**2+4.58*t**3

C = 90.7*t-242.2*t**2+42.4*t**3

D = 2.18+2.82*t

 

z = (A*Ppr)/Y

 

Delta = A*(((1-Y)**4)/(1+(4*Y)+(4*(Y**2))-(4*(Y**3))+(Y**4)-((1-Y)**4)*((2*B*Y)-C*D*Y**(D-1))))

 

Delta = (A/Y)-(A*Ppr)/(Y**2)*(Delta)

 

Cr = (1/Ppr)-(Delta/z)

 

Cg4 = Cr/680

 

# Brill, J.P. y Beggs, H.D.

 

F = 0.3106 - (0.49*(Tpr)) + (0.1824*(Tpr)**2)

E = 9*(Tpr-1)

D = 10**F

C = 0.132-0.32*np.log10(Tpr)

B = (0.62-(0.23*Tpr))*Ppr + ((0.066/(Tpr-0.86))-0.037)*(Ppr**2) + (0.32/(10**E))*(Ppr**6)

A = (1.39*(Tpr-0.92)**0.5)-(0.36*Tpr)-0.10

z = A + ((1-A)/np.exp(B)) + (C*(Ppr**D))

 

Delta = ((1-A)/(((0.62-0.23*Tpr)+(((0.132/(Tpr-0.86))-0.74)*Ppr)+((1.92*Ppr**5)/10**(9*(Tpr-1))))+np.exp(B)))+C*D*(Ppr**(D-1))

 

Cr = (1/Ppr)-(Delta/z)

 

Cg5 = Cr/680

 

print("#"*49)

print("#                                              Método                          #")

print("# Mattar, L., Brar,G.S. y Aziz, K....",round(Cg1,7)," #")

print("# Sarem, A.M.........................",round(float(Cg2),7),"#")

print("# Papay, J...........................",round(Cg3,7),"#")

print("# Hall, K.R. y Yarborough, L.........",round(Cg4,7),"#")

print("# Brill, J.P. y Beggs, H.D...........",round(Cg5,7),"#")

print("#"*49)

 

El programa genera el siguiente mensaje

 

#################################################

#                                             Método                          #

# Mattar, L., Brar,G.S. y Aziz, K.... 0.000127  #

# Sarem, A.M......................... 0.0001682 #

# Papay, J........................... 0.0001203 #

# Hall, K.R. y Yarborough, L......... 0.0001441 #

# Brill, J.P. y Beggs, H.D........... 0.0001138 #

#################################################