def function_inner_loop(pressure,
temperature,
global_molar_fraction,
max_iter=100,
tolerance=1.0e-12,
stability=False):
T = temperature
P = pressure
logging.debug('pressure' + str(P))
yi = z = global_molar_fraction
f_V, Z_V = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
P, T, yi, 'vapor')
PHI_V = f_V / (yi * P)
initial_K_values = calculate_K_values_wilson(P, T, eos_obj.Pc, eos_obj.Tc,
eos_obj.ω)
is_stable, K_michelsen = michelsen_obj(eos_obj, P, T, z, initial_K_values,
max_iter, tolerance)
if stability:
if not is_stable:
msg = str('===> two-phases can be in equilibrium')
else:
msg = str('===> one phase in this @')
print(msg)
logging.debug('K_michelsen' + str(K_michelsen))
logging.debug('One-phase = ' + str(is_stable))
xi = yi #yi / K_michelsen
Sx = np.sum(xi)
Sx0 = 2 * Sx
itermax = 2
for counter in np.arange(itermax):
if is_stable:
Sx = (
Sx + 3.0
) # To force the program stores wrong Sx's value [avoid the solver seeks minimum values of (Sx - 1)]
break
else:
pass
f_L, Z_L = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
P, T, xi, 'liquid')
PHI_L = f_L / (xi * P)
K = PHI_L / PHI_V
xi = yi / K
Sx = np.sum(xi)
logging.debug('iteracao' + str(counter))
logging.debug('K' + str(K))
logging.debug('xi' + str(xi))
logging.debug('Sx = ' + str(Sx) + '\n----')
if (np.abs(Sx - Sx0) < tolerance):
break
else:
xi /= Sx
Sx0 = np.copy(Sx)
return Sx, xi
def inner_loop(self, eos_obj, p, T, z, iteration_michelsen,
tolerance_michelsen):
'''
This function is responsible for a more realistic K (vapor-liquid ratio) value. So, the first estimation
of K is made with Wilson equation. After that, this K_Wilson is fed in Michelsen's code. This, on the other hand,
notifies us if this mixture is stable. Besides that, in case of not stable phase (split in 2 phases),
Michelsen's code also provides a better K estimation.
:iteration_michelsen: is max iteration number used in Michelsen algorithm
:tolerance_michelsen: is the tolerance exigence in Michelsen algorithm
'''
K_wilson = calculate_K_values_wilson(p, T, self.pC, self.Tc, self.AcF)
is_stable, K = michelsen_obj(eos_obj, p, T, z, K_wilson,
iteration_michelsen, tolerance_michelsen)
return is_stable, K
def getting_the_results_from_FlashAlgorithm_main(p, T, pC, Tc, AcF, z):
initial_K_values = calculate_K_values_wilson(p, T, pC, Tc, AcF)
is_stable, K_michelsen = michelsen_obj(eos_obj,
p,
T,
z,
initial_K_values,
max_iter=100,
tolerance=1.0e-12)
K_flash, F_V_flash = flash_obj(rr_obj, eos_obj, p, T, z, K_michelsen)
Vector_ToBe_Optimized = np.append(K_flash, F_V_flash)
result = fsolve(func=flash_obj.flash_residual_function,
x0=Vector_ToBe_Optimized,
args=(T, p, eos_obj, z))
size = result.shape[0]
K_values_newton = np.array(result[0:size - 1])
F_V = result[-1]
return (F_V, is_stable, K_values_newton, initial_K_values)
def function_inner_loop(temperature, pressure, global_molar_fraction, max_iter = 100, tolerance = 1.0e-12, stability=False):
P = pressure
T = temperature
xi = z = global_molar_fraction
f_L, Z_L = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(P, T, xi, 'liquid')
PHI_L = f_L / (xi * P)
initial_K_values = calculate_K_values_wilson(P, T, eos_obj.Pc, eos_obj.Tc, eos_obj.ω)
is_stable, K_michelsen = michelsen_obj(eos_obj, P, T, z, initial_K_values, max_iter, tolerance)
if stability:
if not is_stable:
msg = str('===> two-phases can be in equilibrium')
else:
msg = str('===> one phase in this @')
print(str(msg))
logging.debug('temperature' + str(T))
logging.debug('K_michelsen' + str(K_michelsen))
logging.debug('One-phase = ' + str(is_stable))
yi = xi * K_michelsen
Sy = np.sum(yi)
Sy0 = 2 * Sy
itermax = 2
for counter in np.arange(itermax):
if is_stable:
break
else:
pass
f_V, Z_V = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(P, T, yi, 'vapor')
PHI_V = f_V / (yi * P)
K = PHI_L / PHI_V
yi = xi * K
Sy = np.sum(yi)
logging.debug('iteracao' + str(counter))
logging.debug('K' + str(K))
logging.debug('yi' + str(yi))
logging.debug('Sy' + str(Sy) + '\n----')
if (np.abs(Sy - Sy0) < tolerance):
break
else:
yi /= Sy
Sy0 = np.copy(Sy)
return Sy, yi
def calculate_vapor_liquid_equilibrium(eos_obj,
michelsen_obj,
flash_obj,
prop_obj,
pressure,
temperature,
molar_mass,
global_molar_fractions,
max_iter,
tolerance,
print_statistics=None):
P = pressure
T = temperature
z = global_molar_fractions
Mi = molar_mass
#size = z.shape[0]
# Estimate initial K-values
initial_K_values = calculate_K_values_wilson(pressure, temperature,
eos_obj.Pc, eos_obj.Tc,
eos_obj.ω)
# Check if the mixture is stable and takes Michelsen's K
is_stable, K_michelsen = michelsen_obj(eos_obj, P, T, z, initial_K_values,
max_iter, tolerance)
# Executing the Flash
K_flash, F_V_flash = flash_obj(rr_obj, eos_obj, pressure, temperature,
global_molar_fractions, K_michelsen)
# Good estimate!
Vector_ToBe_Optimized = np.append(K_flash, F_V_flash)
## Use estimates from flash (successive substitutions)!!!
if 0.0 <= F_V_flash <= 1.0:
result, infodict, ier, mesg = fsolve(
func=flash_obj.flash_residual_function,
x0=Vector_ToBe_Optimized,
args=(T, P, eos_obj, z),
full_output=True)
size = result.shape[0]
K_values_newton = result[0:size - 1]
F_V = result[size - 1]
x_i = global_molar_fractions / (F_V * (K_values_newton - 1) + 1)
y_i = K_values_newton * x_i
f_L, Z_L = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
P, T, x_i, 'liquid')
f_V, Z_V = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
P, T, y_i, 'vapor')
rho_L = prop_obj.calculate_density_phase(P, T, Mi, x_i, 'liquid')
rho_V = prop_obj.calculate_density_phase(P, T, Mi, y_i, 'vapor')
if print_statistics:
print('Newton flash converged? %d, %s' % (ier, mesg))
elif F_V_flash < 0.0:
x_i = z
y_i = np.zeros_like(z)
K_values_newton = initial_K_values
rho_L = prop_obj.calculate_densite_phase(P, T, Mi, x_i, 'liquid')
rho_V = 0.0
F_V = 0.0
elif F_V_flash > 1.0:
y_i = z
x_i = np.zeros_like(z)
K_values_newton = initial_K_values
rho_L = 0.0
rho_V = prop_obj.calculate_densite_phase(P, T, Mi, y_i, 'vapor')
F_V = 1.0
else:
raise Exception(
"Nenhuma das @ foram dectadas na calculate_vapor_liquid_equilibrium"
)
return F_V, K_values_newton, x_i, y_i, rho_V, rho_L
def function_inner_loop(p,
T,
z,
max_iter=20,
tolerance=1.0e-20,
stability=False):
'''
These function_inner_loop and function_outer_loop are functions based on Elliott's BUBBLE P algorithm (pg 595)
INTRODUCTORY CHEMICAL ENGINEERING THERMODYNAMICS, 2nd edition, 2012
J. RICHARD ELLIOTT and CARL T. LIRA
'''
logging.debug('Updating the Pressure =====> ' + str(p))
xi = z
Sz = np.sum(z)
assert np.abs(
Sz - 1.0
) < 1.e-5, 'YOUR GLOBAL MOLAR FRACTION MUST BE EQUAL = 1. Check your data' + str(
Sz)
initial_K_values = calculate_K_values_wilson(p, T, pC, Tc, AcF)
is_stable, K = michelsen_obj(eos_obj, p, T, z, initial_K_values, max_iter,
tolerance)
if is_stable == True:
Sy = 1e10
yi = np.zeros_like(z)
else:
if stability:
if not is_stable:
msg = str('===> two-phases can be in equilibrium')
else:
msg = str('===> one phase in this @')
print(str(msg))
logging.debug('K_wilson = ' + str(initial_K_values))
logging.debug('K_michelsen = ' + str(K))
logging.debug(
'One-phase ================================================ > ' +
str(is_stable))
yi = xi * K
f_L, Z_L = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
p, T, xi, 'liquid')
Sy = np.sum(yi)
Sy0 = 2 * Sy
max_loop = 2
for counter in np.arange(max_loop):
f_V, Z_V = eos_obj.calculate_fugacities_with_minimum_gibbs_energy(
p, T, yi, 'vapor')
np.seterr(
divide='ignore', invalid='ignore'
) #Because we can have PHI_V near zero for the no volatile component
K *= f_L / f_V
yi = xi * K
Sy = np.sum(yi)
logging.debug('iteracao' + str(counter))
logging.debug('K' + str(K))
logging.debug('yi' + str(yi))
logging.debug('Sy = ' + str(Sy) + '\n----')
if (np.abs(Sy - Sy0) < tolerance):
break
else:
yi /= Sy
Sy0 = np.copy(Sy)
return Sy, yi
