def from_abstract_state(cls, state: CoolProp.AbstractState):
new_state = cls(state.backend_name(), '&'.join(state.fluid_names()))
# Uses mass fraction to work with incompressible fluids
masses = state.get_mass_fractions()
if len(masses) > 1:
new_state.set_mass_fractions(masses)
try:
rho = state.rhomolar()
T = state.T()
new_state.update(CoolProp.DmolarT_INPUTS, rho, T)
except:
pass
return new_state
class Fluid:
"""Represents a fluid."""
def __init__(self, name: str, eos: str = 'HEOS'):
"""Initiate a Fluid instance.
:param ID: id of fluid
"""
self.name = name
self.eos = eos.upper()
self.state = AbstractState(self.eos, self.name)
if self.state.name() not in ["NitrousOxide"]:
raise NotImplementedError(
f'{self.state.name()} is not supported currently')
self.Tmax = 309.5 # self.state.Tmax()
self.Tmin = 182.23 # self.state.Tmin()
self.pmax = self.state.pmax()
self.pmin = 0
def copy(self):
fluid = Fluid(self.name, self.eos)
fluid.set_state(P=self.state.p(), T=self.state.T())
return fluid
def set_state(self,
D: float = None,
P: float = None,
T: float = None,
Q: float = None,
H: float = None,
S: float = None,
U: float = None):
args_present = {
'D': D is not None,
'P': P is not None,
'T': T is not None,
'Q': Q is not None,
'H': H is not None,
'S': S is not None,
'U': U is not None
}
if sum(args_present.values()) != 2:
raise ValueError(
f'Must have exactly 2 arguments: {sum(args_present.values())} provided'
)
args = []
if args_present['D']:
if args_present['P']:
args = CP.DmassP_INPUTS, D, P
elif args_present['T']:
args = CP.DmassT_INPUTS, D, T
elif args_present['Q']:
args = CP.DmassQ_INPUTS, D, Q
elif args_present['H']:
args = CP.DmassHmass_INPUTS, D, H
elif args_present['S']:
args = CP.DmassSmass_INPUTS, D, S
elif args_present['U']:
args = CP.DmassUmass_INPUTS, D, U
elif args_present['P']:
if args_present['T']:
args = CP.PT_INPUTS, P, T
elif args_present['Q']:
args = CP.PQ_INPUTS, P, Q
elif args_present['H']:
args = CP.HmassP_INPUTS, H, P
elif args_present['S']:
args = CP.PSmass_INPUTS, P, S
elif args_present['U']:
args = CP.PUmass_INPUTS, P, U
elif args_present['T']:
if args_present['Q']:
args = CP.QT_INPUTS, Q, T
elif args_present['H']:
args = CP.HmassT_INPUTS, H, T
elif args_present['S']:
args = CP.SmassT_INPUTS, S, T
elif args_present['U']:
args = CP.TUmass_INPUTS, T, U
elif args_present['Q']:
if args_present['H']:
args = CP.HmassQ_INPUTS, H, Q
elif args_present['S']:
args = CP.QSmass_INPUTS, Q, S
elif args_present['U']:
raise ValueError('Invalid combination: Q and U')
elif args_present['H']:
if args_present['S']:
args = CP.HmassSmass_INPUTS, H, S
elif args_present['U']:
raise ValueError('Invalid combination: H and U')
elif args_present['S'] and args_present['U']:
args = CP.SmassUmass_INPUTS, S, U
else:
raise ValueError('Invalid combination')
try:
self.state.update(*args)
except ValueError:
pass
def Vf(self, S: float):
x = self.chi()
return 1 / (1 /
(1 + S * ((1 - x) / x) * self.rhog([self.state.T()])[0] /
self.rhol([self.state.T()])[0]))
def chi(self):
x = self.state.Q()
if x >= 0:
return x
if self.state.rhomass() > self.rhol([self.state.T()])[0]:
return 0
else:
return 1
def viscosityl(self, T):
b1 = 1.6089
b2 = 2.0439
b3 = 5.24
b4 = 0.0293423
theta = (self.state.T_critical() - b3) / (T - b3)
return b4 * np.exp(b1 * (theta - 1)**(1 / 3) + b2 *
(theta - 1)**(4 / 3))
def viscosityg(self, T):
b1 = 3.3281
b2 = -1.18237
b3 = -0.055155
Tr = T / self.state.T_critical()
return 0.001 * np.exp(b1 + b2 * (1 / Tr - 1)**(1 / 3) + b3 *
(1 / Tr - 1)**(4 / 3)) if (
self.Tmin < T < self.Tmax) else None
def viscosity(self):
T = self.state.T()
mug = self.viscosityg(T)
mul = self.viscosityl(T)
x = self.chi()
rho = self.state.rhomass()
rhol = self.rhol([T])[0]
rhog = self.rhog([T])[0]
return mug * x * rho / rhog + mul * (1 - x) * rho / rhol
def dvg_dP_saturation(self):
dP = 0.002
rho1 = PropsSI('D', 'P', self.state.p() + dP / 2, 'Q', 1, self.name)
rho0 = PropsSI('D', 'P', self.state.p() - dP / 2, 'Q', 1, self.name)
dvg = 1 / rho1 - 1 / rho0
return dvg / dP
def rhol(self, T: Iterable):
return [
PropsSI('D', 'T', t, 'Q', 0, self.eos + "::" + self.name)
for t in T
]
def rhog(self, T: Iterable):
return [
PropsSI('D', 'T', t, 'Q', 1, self.eos + "::" + self.name)
for t in T
]
def psat(self, T: Iterable):
return [
PropsSI('P', 'Q', 0.5, 'T', t, self.eos + "::" + self.name) if
(self.Tmin < t < self.Tmax) else None for t in T
]
def tsat(self, P: Iterable):
return [
PropsSI('T', 'P', P, 'Q', 0.5, self.eos + "::" + self.name) if
(self.pmin < p < self.pmax) else None for p in P
]
def hl(self, T: Iterable):
return [
PropsSI('H', 'T', t, 'Q', 0, self.eos + "::" + self.name) if
(self.Tmin < t < self.Tmax) else None for t in T
]
def hg(self, T: Iterable):
return [
PropsSI('H', 'T', t, 'Q', 1, self.eos + "::" + self.name) if
(self.Tmin < t < self.Tmax) else None for t in T
]
def sl(self, T: Iterable):
return [
PropsSI('S', 'T', t, 'Q', 0, self.eos + "::" + self.name) if
(self.Tmin < t < self.Tmax) else None for t in T
]
def sg(self, T: Iterable):
return [
PropsSI('S', 'T', t, 'Q', 1, self.eos + "::" + self.name) if
(self.Tmin < t < self.Tmax) else None for t in T
]
def __repr__(self):
return f'Fluid({self.name}: p={self.state.p() / 100000:.1f}bar, t={self.state.T():.1f}K)'
