# -*- coding: utf-8 -*-
# BioSTEAM: The Biorefinery Simulation and Techno-Economic Analysis Modules
# Copyright (C) 2020-2023, Yoel Cortes-Pena <yoelcortes@gmail.com>
#
# This module is under the UIUC open-source license. See
# github.com/BioSTEAMDevelopmentGroup/biosteam/blob/master/LICENSE.txt
# for license details.
"""
"""
from __future__ import annotations
import pandas as pd
import numpy as np
import thermosteam as tmo
import flexsolve as flx
from thermosteam import functional as fn, Thermo
from . import indexer
from . import equilibrium as eq
from . import units_of_measure as UofM
from .exceptions import DimensionError, InfeasibleRegion
from chemicals.elements import array_to_atoms, symbol_to_index
from . import utils
from .indexer import nonzeros
from typing import TYPE_CHECKING
from ._phase import valid_phases
from .network import AbstractStream
if TYPE_CHECKING:
from .base import SparseVector, SparseArray
from numpy.typing import NDArray
from typing import Optional, Sequence, Callable
import biosteam as bst
# from .constants import g
MaterialIndexer = tmo.indexer.MaterialIndexer
__all__ = ('Stream',)
# %% Utilities
impact_indicator_basis = tmo.units_of_measure.AbsoluteUnitsOfMeasure('kg')
mol_units = indexer.ChemicalMolarFlowIndexer.units
mass_units = indexer.ChemicalMassFlowIndexer.units
vol_units = indexer.ChemicalVolumetricFlowIndexer.units
class StreamData:
__slots__ = ('_imol', '_T', '_P', '_phases')
def __init__(self, imol, thermal_condition, phases):
self._imol = imol.copy()
self._T = thermal_condition._T
self._P = thermal_condition._P
self._phases = phases
# %%
[docs]
@utils.units_of_measure(UofM.stream_units_of_measure)
@utils.thermo_user
class Stream(AbstractStream):
"""
Create a Stream object that defines material flow rates
along with its thermodynamic state. Thermodynamic and transport
properties of a stream are available as properties, while
thermodynamic equilbrium (e.g. VLE, and bubble and dew points)
are available as methods.
Parameters
----------
ID :
A unique identification. If ID is None, stream will not be registered.
If no ID is given, stream will be registered with a unique ID.
flow :
All flow rates corresponding to defined chemicals.
phase :
'g' for gas, 'l' for liquid, and 's' for solid. Defaults to 'l'.
T :
Temperature [K]. Defaults to 298.15.
P :
Pressure [Pa]. Defaults to 101325.
units :
Flow rate units of measure (only mass, molar, and
volumetric flow rates are valid). Defaults to 'kmol/hr'.
price :
Price per unit mass [USD/kg]. Defaults to 0.
total_flow :
Total flow rate.
thermo :
Thermo object to initialize input and output streams. Defaults to
:meth:`settings.thermo <thermosteam._settings.ProcessSettings.thermo>`.
characterization_factors :
Characterization factors for life cycle assessment.
vlle :
Whether to run rigorous phase equilibrium to determine phases.
Defaults to False.
**chemical_flows : float
ID - flow pairs.
Examples
--------
Before creating a stream, first set the chemicals:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
Create a stream, defining the thermodynamic condition and flow rates:
>>> s1 = tmo.Stream(ID='s1',
... Water=20, Ethanol=10, units='kg/hr',
... T=298.15, P=101325, phase='l')
>>> s1.show(flow='kg/hr') # Use the show method to select units of display
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 10
>>> s1.show(composition=True, flow='kg/hr') # Its also possible to show by composition
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
composition (%): Water 66.7
Ethanol 33.3
------- 30 kg/hr
All flow rates are stored as a sparse array in the `mol` attribute.
These arrays work just like numpy arrays, but are more scalable
(saving memory and increasing speed) for sparse chemical data:
>>> s1.mol # Molar flow rates [kmol/hr]
sparse([1.11 , 0.217])
Mass and volumetric flow rates are also available for convenience:
>>> s1.mass
sparse([20., 10.])
>>> s1.vol
sparse([0.02 , 0.013])
The data of these arrays are linked to the molar flows:
>>> # Mass flows are always up to date with molar flows
>>> s1.mol[0] = 1
>>> s1.mass[0]
18.015
>>> # Changing mass flows changes molar flows
>>> s1.mass[0] *= 2
>>> s1.mol[0]
2.0
>>> # New arrays are not linked to molar flows
>>> s1.mass + 2
sparse([38.031, 12. ])
The temperature, pressure and phase are attributes as well:
>>> (s1.T, s1.P, s1.phase)
(298.15, 101325.0, 'l')
The most convinient way to get and set flow rates is through
the `get_flow` and `set_flow` methods:
>>> # Set flow
>>> s1.set_flow(1, 'gpm', 'Water')
>>> s1.get_flow('gpm', 'Water')
1.0
>>> # Set multiple flows
>>> s1.set_flow([10, 20], 'kg/hr', ('Ethanol', 'Water'))
>>> s1.get_flow('kg/hr', ('Ethanol', 'Water'))
array([10., 20.])
It is also possible to index using IDs through the
`imol`, `imass`, and `ivol` indexers:
>>> s1.imol.show()
ChemicalMolarFlowIndexer (kmol/hr):
(l) Water 1.11
Ethanol 0.2171
>>> s1.imol['Water']
1.1101687012358397
>>> s1.imol['Ethanol', 'Water']
array([0.217, 1.11 ])
Thermodynamic properties are available as stream properties:
>>> s1.H # Enthalpy (kJ/hr)
0.0
Note that the reference enthalpy is 0.0 at the reference
temperature of 298.15 K, and pressure of 101325 Pa.
Retrive the enthalpy at a 10 degC above the reference.
>>> s1.T += 10
>>> s1.H
1083.46
Other thermodynamic properties are temperature and pressure dependent as well:
>>> s1.rho # Density [kg/m3]
909.14
It may be more convinient to get properties with different units:
>>> s1.get_property('rho', 'g/cm3')
0.9091
It is also possible to set some of the properties in different units:
>>> s1.set_property('T', 40, 'degC')
>>> s1.T
313.15
Bubble point and dew point computations can be performed through stream methods:
>>> bp = s1.bubble_point_at_P() # Bubble point at constant pressure
>>> bp
BubblePointValues(T=357.14, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.492 0.508])
The bubble point results contain all results as attributes:
>>> tmo.docround(bp.T) # Temperature [K]
357.1442
>>> bp.y # Vapor composition
array([0.49, 0.51])
Vapor-liquid equilibrium can be performed by setting 2 degrees of freedom from the following list: `T` [Temperature; in K], `P` [Pressure; in Pa], `V` [Vapor fraction], `H` [Enthalpy; in kJ/hr].
Set vapor fraction and pressure of the stream:
>>> s1.vle(P=101325, V=0.5)
>>> s1.show()
MultiStream: s1
phases: ('g', 'l'), T: 364.78 K, P: 101325 Pa
flow (kmol/hr): (g) Water 0.472
Ethanol 0.191
(l) Water 0.638
Ethanol 0.0257
Note that the stream is a now a MultiStream object to manage multiple phases.
Each phase can be accessed separately too:
>>> s1['l'].show()
Stream:
phase: 'l', T: 364.78 K, P: 101325 Pa
flow (kmol/hr): Water 0.638
Ethanol 0.0257
>>> s1['g'].show()
Stream:
phase: 'g', T: 364.78 K, P: 101325 Pa
flow (kmol/hr): Water 0.472
Ethanol 0.191
We can convert a MultiStream object back to a Stream object by setting the phase:
>>> s1.phase = 'l'
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 364.78 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 10
"""
__slots__ = (
'_imol', '_thermal_condition', '_streams',
'_bubble_point_cache', '_dew_point_cache',
'_vle_cache', '_lle_cache', '_sle_cache',
'_price', '_property_cache_key',
'_property_cache', 'characterization_factors', 'equations',
'_original',
# '_velocity', '_height'
)
#: Units of measure for IPython display (class attribute)
display_units = UofM.DisplayUnits(T='K', P='Pa',
flow=('kmol/hr', 'kg/hr', 'm3/hr'),
composition=False,
sort=False,
N=7)
display_notation = UofM.DisplayNotation(T='.5g', P='.6g', flow='.3g')
_units_of_measure = UofM.stream_units_of_measure
_flow_cache = {}
def __init__(self, ID: Optional[str]='',
flow: Sequence[float]=(),
phase: Optional[str]='l',
T: Optional[float]=298.15,
P: Optional[float]=101325.,
units: Optional[str]=None,
price: Optional[float]=0.,
total_flow: Optional[float]=None,
thermo: Optional[Thermo]=None,
characterization_factors: Optional[dict[str, float]]=None,
vlle: Optional[bool]=False,
# velocity=0., height=0.,
**chemical_flows:float):
self.equations: dict[str, list[Callable]] = {}
#: Characterization factors for life cycle assessment [impact/kg].
self.characterization_factors: dict[str, float] = {} if characterization_factors is None else {}
self._thermal_condition = tmo.ThermalCondition(T, P)
thermo = self._load_thermo(thermo)
chemicals = thermo.chemicals
self.price = price
# self.velocity = velocity
# self.height = height
if units:
name, factor = self._get_flow_name_and_factor(units)
if name == 'mass':
group_wt_compositions = chemicals._group_wt_compositions
for cID in tuple(chemical_flows):
if cID in group_wt_compositions:
compositions = group_wt_compositions[cID]
group_flow = chemical_flows.pop(cID)
chemical_group = chemicals[cID]
for i in range(len(chemical_group)):
chemical_flows[chemical_group[i]._ID] = group_flow * compositions[i]
elif name == 'vol':
group_wt_compositions = chemicals._group_wt_compositions
for cID in chemical_flows:
if cID in group_wt_compositions:
raise ValueError(f"cannot set volumetric flow by chemical group '{i}'")
self._init_indexer(flow, phase, chemicals, chemical_flows)
mol = self.mol
flow = getattr(self, name)
if total_flow is not None: mol *= total_flow / mol.sum()
material_data = mol / factor
flow[:] = material_data
else:
self._init_indexer(flow, phase, chemicals, chemical_flows)
if total_flow:
mol = self.mol
mol *= total_flow / mol.sum()
self._sink = self._source = None
self.reset_cache()
self._register(ID)
if vlle:
self.vlle(T, P)
data = self._imol.data
self.phases = [j for i, j in enumerate(self.phases) if data[i].any()]
@classmethod
def from_data(cls, data, ID=None, price=0., characterization_factors=None, thermo=None):
self = cls.__new__(cls)
self.__init__(
ID,
characterization_factors=characterization_factors,
price=price,
thermo=thermo,
)
self.set_data(data)
return self
def __getitem__(self, key):
phase = self.phase
if key.lower() == phase.lower(): return self
raise tmo.UndefinedPhase(phase)
def __reduce__(self):
return self.from_data, (self.get_data(), self._ID, self._price, self.characterization_factors, self._thermo)
def equation(self, variable, f=None):
if f is None: return lambda f: self.equation(variable, f)
equations = self.equations
if variable in equations:
equations[variable].append(f)
else:
equations[variable] = [f]
def _create_linear_equations(self, variable):
equations = self.equations
if variable in equations:
return [i() for i in equations[variable]]
else:
return []
def _get_decoupled_variable(self, variable): pass
def _update_decoupled_variable(self, variable, value):
if variable == 'material':
value[value < 0] = 0
self.mol[:] = value
else:
raise NotImplementedError(f'variable {variable!r} cannot be updated')
[docs]
def scale(self, scale):
"""
Multiply flow rate by given scale.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=1)
>>> s1.scale(100)
>>> s1.F_mol
100.0
"""
self._imol.data *= scale
rescale = scale
[docs]
def reset_flow(self, phase=None, units=None, total_flow=None, **chemical_flows):
"""
Convinience method for resetting flow rate data.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=1)
>>> s1.reset_flow(Ethanol=1, phase='g', units='kg/hr', total_flow=2)
>>> s1.show('cwt')
Stream: s1
phase: 'g', T: 298.15 K, P: 101325 Pa
composition (%): Ethanol 100
------- 2 kg/hr
"""
imol = self._imol
imol.empty()
if phase: imol.phase = phase
if chemical_flows:
keys, values = zip(*chemical_flows.items())
if units is None:
self.imol[keys] = values
else:
self.set_flow(values, units, keys)
if total_flow:
if units is None:
self.F_mol = total_flow
else:
self.set_total_flow(total_flow, units)
def _reset_thermo(self, thermo):
if thermo is self._thermo: return
self._thermo = thermo
self._imol.reset_chemicals(thermo.chemicals)
self.reset_cache()
if hasattr(self, '_streams'):
for phase, stream in self._streams.items():
stream._imol = self._imol.get_phase(phase)
stream._thermo = thermo
[docs]
def get_CF(self, key: str, basis : Optional[str]=None, units: Optional[str]=None):
"""
Returns the life-cycle characterization factor on a kg basis given the
impact indicator key.
Parameters
----------
key :
Key of impact indicator.
basis :
Basis of characterization factor. Mass is the only valid dimension (for now).
Defaults to 'kg'.
units :
Units of impact indicator. Before using this argument, the default units
of the impact indicator should be defined with
:meth:`settings.define_impact_indicator <thermosteam._settings.ProcessSettings.define_impact_indicator>`.
Units must also be dimensionally consistent with the default units.
"""
try:
value = self.characterization_factors[key]
except:
return 0.
if units is not None:
original_units = tmo.settings.get_impact_indicator_units(key)
value = original_units.convert(value, units)
if basis is not None:
value /= impact_indicator_basis.conversion_factor(basis)
return value
[docs]
def set_CF(self, key: str, value: float, basis : Optional[str]=None, units: Optional[str]=None):
"""
Set the life-cycle characterization factor on a kg basis given the
impact indicator key and the units of measure.
Parameters
----------
key :
Key of impact indicator.
value :
Characterization factor value.
basis :
Basis of characterization factor. Mass is the only valid dimension (for now).
Defaults to 'kg'.
units :
Units of impact indicator. Before using this argument, the default units
of the impact indicator should be defined with
:meth:`settings.define_impact_indicator <thermosteam._settings.ProcessSettings.define_impact_indicator>`.
Units must also be dimensionally consistent with the default units.
"""
if units is not None:
original_units = tmo.settings.get_impact_indicator_units(key)
value = original_units.unconvert(value, units)
if basis is not None:
value *= impact_indicator_basis.conversion_factor(basis)
self.characterization_factors[key] = value
[docs]
def get_impact(self, key):
"""Return hourly rate of the impact indicator given the key."""
cfs = self.characterization_factors
return cfs[key] * self.F_mass if key in cfs else 0.
[docs]
def empty_negative_flows(self):
"""
Replace flows of all components with negative values with 0.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=1, Ethanol=-1)
>>> s1.empty_negative_flows()
>>> s1.show()
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 1
"""
self._imol.data.remove_negatives()
[docs]
def shares_flow_rate_with(self, other):
"""
Return whether other stream shares data with this one.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> s1 = tmo.Stream('s1')
>>> other = s1.flow_proxy()
>>> s1.shares_flow_rate_with(other)
True
>>> s1 = tmo.MultiStream('s1', phases=('l', 'g'))
>>> s1['g'].shares_flow_rate_with(s1)
True
>>> s2 = tmo.MultiStream('s2', phases=('l', 'g'))
>>> s1['g'].shares_flow_rate_with(s2)
False
>>> s1['g'].shares_flow_rate_with(s2['g'])
False
>>> s1 = tmo.MultiStream('s1')
>>> other = s1.flow_proxy()
>>> s1.shares_flow_rate_with(other)
True
>>> s1 = tmo.MultiStream('s1', phases=('l', 'g'))
>>> s1.shares_flow_rate_with(s1['g'])
True
>>> s2 = tmo.MultiStream('s2', phases=('l', 'g'))
>>> s2.shares_flow_rate_with(s1['g'])
False
>>> s1.shares_flow_rate_with(s2)
False
"""
return self._imol.data.shares_data_with(other._imol.data)
[docs]
def as_stream(self):
"""Does nothing."""
[docs]
def get_data(self):
"""
Return a StreamData object containing data on material flow rates,
temperature, pressure, and phase(s).
See Also
--------
Stream.set_data
Examples
--------
Get and set data from stream at different conditions
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> stream = tmo.Stream('stream', Water=10)
>>> data = stream.get_data()
>>> stream.vle(V=0.5, P=101325)
>>> data_vle = stream.get_data()
>>> stream.set_data(data)
>>> stream.show()
Stream: stream
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 10
>>> stream.set_data(data_vle)
>>> stream.show()
MultiStream: stream
phases: ('g', 'l'), T: 373.12 K, P: 101325 Pa
flow (kmol/hr): (g) Water 5
(l) Water 5
Note that only StreamData objects are valid for this method:
>>> stream.set_data({'T': 298.15})
Traceback (most recent call last):
ValueError: stream_data must be a StreamData object; not dict
"""
return StreamData(self._imol, self._thermal_condition, self.phases)
[docs]
def set_data(self, stream_data):
"""
Set material flow rates, temperature, pressure, and phase(s) through a
StreamData object
See Also
--------
Stream.get_data
"""
if isinstance(stream_data, StreamData):
self.phases = stream_data._phases
self._imol.copy_like(stream_data._imol)
self._thermal_condition.copy_like(stream_data)
else:
raise ValueError(f'stream_data must be a StreamData object; not {type(stream_data).__name__}')
@property
def price(self) -> float:
"""Price of stream per unit mass [USD/kg]."""
return self._price
@price.setter
def price(self, price):
if np.isfinite(price):
self._price = float(price)
else:
raise AttributeError(f'price must be finite, not {price}')
# @property
# def velocity(self) -> float:
# """Velocity of stream [m/s]."""
# return self._velocity
# @velocity.setter
# def velocity(self, velocity):
# if np.isfinite(velocity):
# self._velocity = float(velocity)
# else:
# raise AttributeError(f'velocity must be finite, not {velocity}')
# @property
# def height(self) -> float:
# """Relative height of stream [m]."""
# return self._height
# @height.setter
# def height(self, height):
# if np.isfinite(height):
# self._height = float(height)
# else:
# raise AttributeError(f'height must be finite, not {height}')
# @property
# def potential_energy(self) -> float:
# """Potential energy flow rate [kW]"""
# return (g * self.height * self.F_mass) / 3.6e6
# @property
# def kinetic_energy(self):
# """Kinetic energy flow rate [kW]"""
# return 0.5 * self.F_mass / 3.6e6 * self._velocity * self._velocity
[docs]
def isempty(self):
"""
Return whether or not stream is empty.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> stream = tmo.Stream()
>>> stream.isempty()
True
"""
return self._imol.isempty()
[docs]
def sanity_check(self):
"""
Raise an InfeasibleRegion error if flow rates are infeasible.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> s1 = tmo.Stream('s1')
>>> s1.sanity_check()
>>> s1.mol[0] = -1.
>>> s1.sanity_check()
Traceback (most recent call last):
InfeasibleRegion: negative material flow rate is infeasible
"""
material = self._imol.data
if material.has_negatives(): raise InfeasibleRegion('negative material flow rate')
@property
def vapor_fraction(self) -> float:
"""Molar vapor fraction."""
return 1.0 if self.phase in 'gG' else 0.0
@property
def liquid_fraction(self) -> float:
"""Molar liquid fraction."""
return 1.0 if self.phase in 'lL' else 0.0
@property
def solid_fraction(self) -> float:
"""Molar solid fraction."""
return 1.0 if self.phase in 'sS' else 0.0
@property
def main_chemical(self) -> str:
"""ID of chemical with the largest mol fraction in stream."""
return self.chemicals.tuple[self.mol.argmax()].ID
def _init_indexer(self, flow, phase, chemicals, chemical_flows):
"""Initialize molar flow rates."""
if len(flow) == 0:
if chemical_flows:
imol = indexer.ChemicalMolarFlowIndexer(phase, chemicals=chemicals, **chemical_flows)
else:
imol = indexer.ChemicalMolarFlowIndexer.blank(phase, chemicals)
else:
if chemical_flows: ValueError("may specify either 'flow' or 'chemical_flows', but not both")
if isinstance(flow, indexer.ChemicalMolarFlowIndexer):
imol = flow
imol.phase = phase
else:
imol = indexer.ChemicalMolarFlowIndexer.from_data(
np.asarray(flow, dtype=float), phase, chemicals)
self._imol = imol
[docs]
def reset_cache(self):
"""Reset cache regarding equilibrium methods."""
self._bubble_point_cache = eq.BubblePointCache()
self._dew_point_cache = eq.DewPointCache()
self._property_cache_key = None, None
self._property_cache = {}
@classmethod
def _get_flow_name_and_factor(cls, units):
cache = cls._flow_cache
if units in cache:
name, factor = cache[units]
else:
dimensionality = UofM.get_dimensionality(units)
if dimensionality == mol_units.dimensionality:
name = 'mol'
factor = mol_units.conversion_factor(units)
elif dimensionality == mass_units.dimensionality:
name = 'mass'
factor = mass_units.conversion_factor(units)
elif dimensionality == vol_units.dimensionality:
name = 'vol'
factor = vol_units.conversion_factor(units)
else:
raise DimensionError("dimensions for flow units must be in molar, "
"mass or volumetric flow rates, not "
f"'{dimensionality}'")
cache[units] = name, factor
return name, factor
### Property getters ###
[docs]
def get_atomic_flow(self, symbol):
"""
Return flow rate of atom [kmol / hr] given the atomic symbol.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> stream = tmo.Stream(Water=1)
>>> stream.get_atomic_flow('H') # kmol/hr of H
2.0
>>> stream.get_atomic_flow('O') # kmol/hr of O
1.0
"""
return (self.chemicals.formula_array[symbol_to_index[symbol], :] * self.mol).sum()
[docs]
def get_atomic_flows(self):
"""
Return dictionary of atomic flow rates [kmol / hr].
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> stream = tmo.Stream(Water=1)
>>> stream.get_atomic_flows()
{'H': 2.0, 'O': 1.0}
"""
return array_to_atoms(self.chemicals.formula_array @ self.mol)
[docs]
def get_flow(self, units: str, key: Optional[Sequence[str]|str]=...):
"""
Return an flow rates in requested units.
Parameters
----------
units :
Units of measure.
key :
Chemical identifiers.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1.get_flow('kg/hr', 'Water')
20.0
"""
name, factor = self._get_flow_name_and_factor(units)
indexer = getattr(self, 'i' + name)
return factor * indexer[key]
[docs]
def set_flow(self, data: NDArray[float]|float, units: str, key: Optional[Sequence[str]|str]=...):
"""
Set flow rates in given units.
Parameters
----------
data :
Flow rate data.
units :
Units of measure.
key :
Chemical identifiers.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream(ID='s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1.set_flow(10, 'kg/hr', 'Water')
>>> s1.get_flow('kg/hr', 'Water')
10.0
"""
name, factor = self._get_flow_name_and_factor(units)
indexer = getattr(self, 'i' + name)
indexer[key] = np.asarray(data, dtype=float) / factor
[docs]
def get_total_flow(self, units: str):
"""
Get total flow rate in given units.
Parameters
----------
units :
Units of measure.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1.get_total_flow('kg/hr')
30.0
"""
name, factor = self._get_flow_name_and_factor(units)
flow = getattr(self, 'F_' + name)
return factor * flow
[docs]
def set_total_flow(self, value: float, units: str):
"""
Set total flow rate in given units keeping the composition constant.
Parameters
----------
value :
New total flow rate.
units :
Units of measure.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1.set_total_flow(1.0,'kg/hr')
>>> s1.get_total_flow('kg/hr')
0.9999999999999999
"""
name, factor = self._get_flow_name_and_factor(units)
setattr(self, 'F_' + name, value / factor)
### Stream data ###
[docs]
def get_downstream_units(self, ends=None, facilities=True):
"""Return a set of all units downstream."""
sink = self._sink
units = sink.get_downstream_units(ends, facilities)
units.add(sink)
return units
[docs]
def get_upstream_units(self, ends=None, facilities=True):
"""Return a set of all units upstream."""
source = self._source
units = source.get_upstream_units(ends, facilities)
units.add(source)
return units
@property
def thermal_condition(self) -> tmo.ThermalCondition:
"""
Contains the temperature and pressure conditions
of the stream.
"""
return self._thermal_condition
@property
def T(self) -> float:
"""Temperature [K]."""
return self._thermal_condition._T
@T.setter
def T(self, T):
self._thermal_condition._T = float(T)
@property
def P(self) -> float:
"""Pressure [Pa]."""
return self._thermal_condition._P
@P.setter
def P(self, P):
self._thermal_condition._P = float(P)
@property
def phase(self) -> str:
"""Phase of stream."""
return self._imol._phase._phase
@phase.setter
def phase(self, phase):
self._imol._phase.phase = phase
@property
def mol(self) -> NDArray[float]:
"""Molar flow rates [kmol/hr]."""
return self._imol.data
@mol.setter
def mol(self, value):
mol = self.mol
if mol is not value: mol[:] = value
@property
def mass(self) -> SparseVector|SparseArray:
"""Mass flow rates [kg/hr]."""
return self.imass.data
@mass.setter
def mass(self, value):
mass = self.mass
if mass is not value: mass[:] = value
@property
def vol(self) -> SparseVector|SparseArray:
"""Volumetric flow rates [m3/hr]."""
return self.ivol.data
@vol.setter
def vol(self, value):
vol = self.vol
if vol is not value:
vol[:] = value
@property
def imol(self) -> indexer.Indexer:
"""Flow rate indexer with data [kmol/hr]."""
return self._imol
@property
def imass(self) -> indexer.Indexer:
"""Flow rate indexer with data [kg/hr]."""
return self._imol.by_mass()
@property
def ivol(self) -> indexer.Indexer:
"""Flow rate indexer with data [m3/hr]."""
return self._imol.by_volume(self._thermal_condition)
### Net flow properties ###
@property
def cost(self) -> float:
"""Total cost of stream [USD/hr]."""
return self.price * self.F_mass
@property
def F_mol(self) -> float:
"""Total molar flow rate [kmol/hr]."""
return self._imol.data.sum()
@F_mol.setter
def F_mol(self, value):
F_mol = self.F_mol
if not F_mol: raise AttributeError("undefined composition; cannot set flow rate")
self._imol.data *= value/F_mol
@property
def F_mass(self) -> float:
"""Total mass flow rate [kg/hr]."""
return np.dot(self.chemicals.MW, self.mol)
@F_mass.setter
def F_mass(self, value):
F_mass = self.F_mass
if F_mass:
self.imol.data *= value/F_mass
elif value:
raise AttributeError("undefined composition; cannot set flow rate")
else:
self.empty()
@property
def F_vol(self) -> float:
"""Total volumetric flow rate [m3/hr]."""
F_mol = self.F_mol
return 1000. * self.V * F_mol if F_mol else 0.
@F_vol.setter
def F_vol(self, value):
F_vol = self.F_vol
if not F_vol: raise AttributeError("undefined composition; cannot set flow rate")
self.imol.data *= value / F_vol
@property
def H(self) -> float:
"""Enthalpy flow rate [kJ/hr]."""
return self._get_property('H', flow=True)
@H.setter
def H(self, H: float):
if not H and self.isempty(): return
try:
self.T = self.mixture.solve_T_at_HP(
self.phase, self.mol, H, *self._thermal_condition
)
except Exception as error: # pragma: no cover
phase = self.phase.lower()
if phase == 'g':
# Maybe too little heat, liquid must be present
self.phase = 'l'
elif phase == 'l':
# Maybe too much heat, gas must be present
self.phase = 'g'
else:
raise error
self.T = self.mixture.solve_T_at_HP(
self.phase, self.mol, H, *self._thermal_condition
)
@property
def h(self) -> float:
"""Specific enthalpy [kJ/kmol]."""
return self._get_property('H')
@h.setter
def h(self, h: float):
if not h and self.isempty(): return
z_mol = self.z_mol
try:
self.T = self.mixture.solve_T_at_HP(
self.phase, z_mol, h, *self._thermal_condition
)
except Exception as error: # pragma: no cover
phase = self.phase.lower()
if phase == 'g':
# Maybe too little heat, liquid must be present
self.phase = 'l'
elif phase == 'l':
# Maybe too much heat, gas must be present
self.phase = 'g'
else:
raise error
self.T = self.mixture.solve_T_at_HP(
self.phase, z_mol, h, *self._thermal_condition
)
@property
def S(self) -> float:
"""Absolute entropy flow rate [kJ/hr/K]."""
return self._get_property('S', flow=True)
@S.setter
def S(self, S: float):
if not S and self.isempty(): return
try:
self.T = self.mixture.solve_T_at_SP(
self.phase, self.mol, S, *self._thermal_condition
)
except Exception as error: # pragma: no cover
phase = self.phase.lower()
if phase == 'g':
# Maybe too little heat, liquid must be present
self.phase = 'l'
elif phase == 'l':
# Maybe too much heat, gas must be present
self.phase = 'g'
else:
raise error
self.S = self.mixture.solve_T_at_SP(
self.phase, self.mol, S, *self._thermal_condition
)
@property
def Hnet(self) -> float:
"""Total enthalpy flow rate (including heats of formation) [kJ/hr]."""
return self.H + self.Hf
@Hnet.setter
def Hnet(self, Hnet):
self.H = Hnet - self.Hf
@property
def Hf(self) -> float:
"""Enthalpy of formation flow rate [kJ/hr]."""
return (self.chemicals.Hf * self.mol).sum()
@property
def LHV(self) -> float:
"""Lower heating value flow rate [kJ/hr]."""
return (self.chemicals.LHV * self.mol).sum()
@property
def HHV(self) -> float:
"""Higher heating value flow rate [kJ/hr]."""
return (self.chemicals.HHV * self.mol).sum()
@property
def Hvap(self) -> float:
"""Enthalpy of vaporization flow rate [kJ/hr]."""
return self._get_property('Hvap', flow=True, nophase=True)
def _get_property(self, name, flow=False, nophase=False):
property_cache = self._property_cache
thermal_condition = self._thermal_condition
imol = self._imol
data = imol.data
total = data.sum()
if total == 0.:
return 0. if flow else None
else:
composition = data / total
composition_key = composition.dct
if nophase:
literal = (thermal_condition._T, thermal_condition._P)
else:
phase = imol._phase._phase
literal = (phase, thermal_condition._T, thermal_condition._P)
last_literal, last_composition_key = self._property_cache_key
if literal == last_literal and (composition_key == last_composition_key):
if name in property_cache:
value = property_cache[name]
return value * total if flow else value
else:
property_cache.clear()
self._property_cache_key = (literal, composition_key.copy())
calculate = getattr(self.mixture, name)
if nophase:
property_cache[name] = value = calculate(
composition, *self._thermal_condition
)
else:
property_cache[name] = value = calculate(
phase, composition, *self._thermal_condition
)
return value * total if flow else value
@property
def C(self) -> float:
"""Isobaric heat capacity flow rate [kJ/K/hr]."""
return self._get_property('Cn', flow=True)
### Composition properties ###
@property
def z_mol(self) -> NDArray[float]:
"""Molar composition."""
mol = self.mol
z = mol / mol.sum()
z = z.to_array()
z.setflags(0)
return z
@property
def z_mass(self) -> NDArray[float]:
"""Mass composition."""
mass = self.chemicals.MW * self.mol
F_mass = mass.sum()
if F_mass == 0:
z = mass
else:
z = mass / mass.sum()
z.setflags(0)
return z
@property
def z_vol(self) -> NDArray[float]:
"""Volumetric composition."""
vol = self.vol.to_array()
z = vol / vol.sum()
z.setflags(0)
return z
@property
def MW(self) -> float:
"""Overall molecular weight."""
return self.mixture.MW(self.mol)
@property
def V(self) -> float:
"""Molar volume [m^3/mol]."""
return self._get_property('V')
@property
def kappa(self) -> float:
"""Thermal conductivity [W/m/k]."""
return self._get_property('kappa')
@property
def Cn(self) -> float:
"""Molar isobaric heat capacity [J/mol/K]."""
return self._get_property('Cn')
@property
def mu(self) -> float:
"""Hydrolic viscosity [Pa*s]."""
return self._get_property('mu')
@property
def sigma(self) -> float:
"""Surface tension [N/m]."""
return self._get_property('sigma', nophase=True)
@property
def epsilon(self) -> float:
"""Relative permittivity [-]."""
return self._get_property('epsilon', nophase=True)
@property
def Cp(self) -> float:
"""Isobaric heat capacity [J/g/K]."""
return self.Cn / self.MW
@property
def alpha(self) -> float:
"""Thermal diffusivity [m^2/s]."""
return fn.alpha(self.kappa,
self.rho,
self.Cp * 1000.)
@property
def rho(self) -> float:
"""Density [kg/m^3]."""
V = self.V
if V is None: return V
return fn.V_to_rho(V, self.MW)
@property
def nu(self) -> float:
"""Kinematic viscosity [m^2/s]."""
mu = self.mu
if mu is None: return mu
return fn.mu_to_nu(mu, self.rho)
@property
def Pr(self) -> float:
"""Prandtl number [-]."""
return fn.Pr(self.Cp * 1000,
self.kappa,
self.mu)
### Stream methods ###
@property
def available_chemicals(self) -> list[tmo.Chemical]:
"""All chemicals with nonzero flow."""
chemicals = self.chemicals.tuple
return [chemicals[i] for i in self.mol.nonzero_keys()]
[docs]
def in_thermal_equilibrium(self, other):
"""
Return whether or not stream is in thermal equilibrium with
another stream.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> stream = Stream(Water=1, T=300)
>>> other = Stream(Water=1, T=300)
>>> stream.in_thermal_equilibrium(other)
True
"""
return self._thermal_condition.in_equilibrium(other._thermal_condition)
[docs]
@classmethod
def sum(cls, streams, ID=None, thermo=None, energy_balance=True, vle=False):
"""
Return a new Stream object that represents the sum of all given streams.
Examples
--------
Sum two streams:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s_sum = tmo.Stream.sum([s1, s1], 's_sum')
>>> s_sum.show(flow='kg/hr')
Stream: s_sum
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
Ethanol 20
Sum two streams with new property package:
>>> thermo = tmo.Thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s_sum = tmo.Stream.sum([s1, s1], 's_sum', thermo)
>>> s_sum.show(flow='kg/hr')
Stream: s_sum
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
Ethanol 20
"""
new = cls(ID, thermo=thermo)
if streams: new.copy_thermal_condition(streams[0])
new.mix_from(streams, energy_balance, vle)
return new
[docs]
def separate_out(self, other, energy_balance=True):
"""
Separate out given stream from this one.
Examples
--------
Separate out another stream with the same thermodynamic property package:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=30, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2', Water=10, Ethanol=5, units='kg/hr')
>>> s1.separate_out(s2)
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 5
It's also possible to separate out streams with different property packages
so long as all chemicals are defined in the mixed stream's property
package:
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> s1 = tmo.Stream('s1', Water=40, units='kg/hr')
>>> tmo.settings.set_thermo(['Ethanol'], cache=True)
>>> s2 = tmo.Stream('s2', Ethanol=20, units='kg/hr')
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s_mix = tmo.Stream.sum([s1, s2], 's_mix')
>>> s_mix.separate_out(s2)
>>> s_mix.show(flow='kg/hr')
Stream: s_mix
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
Removing empty streams is fine too:
>>> s1.empty(); s_mix.separate_out(s1)
>>> s_mix.show(flow='kg/hr')
Stream: s_mix
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
"""
if other:
if self is other: self.empty()
if energy_balance: H_new = self.H - other.H
self._imol.separate_out(other._imol)
if energy_balance: self.H = H_new
[docs]
def mix_from(self, others, energy_balance=True, vle=False, Q=0., conserve_phases=False):
"""
Mix all other streams into this one, ignoring its initial contents.
Notes
-----
When streams at different pressures are mixed, BioSTEAM assumes valves
reduce the pressure of the streams being mixed to prevent backflow
(pressure needs to decrease in the direction of flow according to
Bernoulli's principle). The outlet pressure will be the minimum pressure
of all streams being mixed.
Examples
--------
Mix two streams with the same thermodynamic property package:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = s1.copy('s2')
>>> s1.mix_from([s1, s2])
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
Ethanol 20
It's also possible to mix streams with different property packages
so long as all chemicals are defined in the mixed stream's property
package:
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> s1 = tmo.Stream('s1', Water=40, units='kg/hr')
>>> tmo.settings.set_thermo(['Ethanol'], cache=True)
>>> s2 = tmo.Stream('s2', Ethanol=20, units='kg/hr')
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s_mix = tmo.Stream('s_mix')
>>> s_mix.mix_from([s1, s2])
>>> s_mix.show(flow='kg/hr')
Stream: s_mix
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 40
Ethanol 20
Mixing empty streams is fine too:
>>> s1.empty(); s2.empty(); s_mix.mix_from([s1, s2])
>>> s_mix.show()
Stream: s_mix
phase: 'l', T: 298.15 K, P: 101325 Pa
flow: 0
"""
streams = []
isa = isinstance
for i in others:
if isa(i, Stream):
if not i.isempty(): streams.append(i)
elif i:
Q += i.heat # Must be a heat or power object, assume power turns to heat
N_streams = len(streams)
if N_streams == 0:
self.empty()
elif N_streams == 1:
if energy_balance:
self.copy_like(streams[0])
else:
self.copy_flow(streams[0])
else:
self.P = P = min([i.P for i in streams])
if conserve_phases:
phases = self.phase + ''.join([i.phase for i in others])
self.phases = phases
if vle:
self._imol.mix_from([i._imol for i in streams])
if energy_balance:
H = sum([i.H for i in streams], Q)
self.vle(H=H, P=P)
else:
self.vle(T=self.T, P=P)
self.reduce_phases()
else:
if energy_balance:
self._imol.mix_from([i._imol for i in streams])
H = sum([i.H for i in streams], Q)
if conserve_phases:
self.H = H
else:
try:
self.H = H
except:
self.phases = self.phase + ''.join([i.phase for i in others])
self._imol.mix_from([i._imol for i in streams])
self.H = H
else:
self._imol.mix_from([i._imol for i in streams])
[docs]
def split_to(self, s1, s2, split, energy_balance=True):
"""
Split molar flow rate from this stream to two others given
the split fraction or an array of split fractions.
Examples
--------
>>> import thermosteam as tmo
>>> chemicals = tmo.Chemicals(['Water', 'Ethanol'], cache=True)
>>> tmo.settings.set_thermo(chemicals)
>>> s = tmo.Stream('s', Water=20, Ethanol=10, units='kg/hr')
>>> s1 = tmo.Stream('s1')
>>> s2 = tmo.Stream('s2')
>>> split = chemicals.kwarray(dict(Water=0.5, Ethanol=0.1))
>>> s.split_to(s1, s2, split)
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 10
Ethanol 1
>>> s2.show(flow='kg/hr')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 10
Ethanol 9
"""
mol = self.mol
chemicals = self.chemicals
values = mol * split
dummy = mol - values
if energy_balance:
tc1 = s1._thermal_condition
tc2 = s2._thermal_condition
tc = self._thermal_condition
tc1._T = tc2._T = tc._T
tc1._P = tc2._P = tc._P
s1.phase = s2.phase = self.phase
if s1.chemicals is chemicals:
s1.mol[:] = values
else:
CASs, values = zip(*[(i, j) for i, j in zip(chemicals.CASs, values) if j])
s1.empty()
s1._imol[CASs] = values
values = dummy
if s2.chemicals is chemicals:
s2.mol[:] = values
else:
s2.empty()
CASs, values = zip(*[(i, j) for i, j in zip(chemicals.CASs, values) if j])
s2._imol[CASs] = values
[docs]
def link_with(self, other: Stream,
flow: Optional[bool]=True,
phase: Optional[bool]=True,
TP: Optional[bool]=True):
"""
Link with another stream.
Parameters
----------
other :
flow :
Whether to link the flow rate data. Defaults to True.
phase :
Whether to link the phase. Defaults to True.
TP :
Whether to link the temperature and pressure. Defaults to True.
See Also
--------
:obj:`~Stream.flow_proxy`
:obj:`~Stream.proxy`
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2')
>>> s2.link_with(s1)
>>> s1.mol is s2.mol
True
>>> s2.thermal_condition is s1.thermal_condition
True
>>> s1.phase = 'g'
>>> s2.phase
'g'
"""
if not isinstance(other._imol, self._imol.__class__):
at_unit = f" at unit {self.source}" if self.source is other.sink else ""
raise RuntimeError(f"stream {self} cannot link with stream {other}" + at_unit
+ "; streams must have the same class to link")
if TP and flow and (phase or self._imol.data.ndim == 2):
self._imol._data_cache = other._imol._data_cache
else:
self._imol._data_cache.clear()
if TP:
self._thermal_condition = other._thermal_condition
if flow:
self._imol.data = other._imol.data
if phase and self._imol.data.ndim == 1:
self._imol._phase = other._imol._phase
[docs]
def unlink(self):
"""
Unlink stream from other streams.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2')
>>> s2.link_with(s1)
>>> s1.unlink()
>>> s2.mol is s1.mol
False
>>> s1.phases = s2.phases = ('l', 'g')
>>> s2.link_with(s1)
>>> s1.imol.data is s2.imol.data
True
>>> s1.unlink()
>>> s1.imol.data is s2.imol.data
False
MultiStream phases cannot be unlinked:
>>> s1 = tmo.MultiStream(None, phases=('l', 'g'))
>>> s1['g'].unlink()
Traceback (most recent call last):
RuntimeError: phase is locked; stream cannot be unlinked
"""
imol = self._imol
if hasattr(imol, '_phase'):
if isinstance(imol._phase, tmo._phase.LockedPhase):
raise RuntimeError('phase is locked; stream cannot be unlinked')
else:
imol._phase = imol._phase.copy()
imol._data_cache.clear()
imol.data = imol.data.copy()
self._thermal_condition = self._thermal_condition.copy()
self.reset_cache()
[docs]
def copy_like(self, other):
"""
Copy all conditions of another stream.
Examples
--------
Copy data from another stream with the same property package:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2', Water=2, units='kg/hr')
>>> s1.copy_like(s2)
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 2
Copy data from another stream with a different property package:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> tmo.settings.set_thermo(['Water'], cache=True)
>>> s2 = tmo.Stream('s2', Water=2, units='kg/hr')
>>> s1.copy_like(s2)
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 2
"""
if isinstance(other.imol, MaterialIndexer):
phases = other.phases
if len(phases) == 1:
phase, = phases
self.phase = phase
self.mol.copy_like(other.imol[phase])
return
else:
self.phases = other.phases
imol = other._imol
else:
imol = other._imol
self._imol.copy_like(imol)
self._thermal_condition.copy_like(other._thermal_condition)
[docs]
def copy_thermal_condition(self, other):
"""
Copy thermal conditions (T and P) of another stream.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=2, units='kg/hr')
>>> s2 = tmo.Stream('s2', Water=1, units='kg/hr', T=300.00)
>>> s1.copy_thermal_condition(s2)
>>> s1.show(flow='kg/hr')
Stream: s1
phase: 'l', T: 300 K, P: 101325 Pa
flow (kg/hr): Water 2
"""
self._thermal_condition.copy_like(other._thermal_condition)
[docs]
def copy_phase(self, other):
"""Copy phase from another stream."""
try:
self._imol._phase._phase = other._imol._phase._phase
except AttributeError as e:
if isinstance(other, tmo.MultiStream):
raise ValueError('cannot copy phase from stream with multiple phases')
raise e from None
[docs]
def copy_flow(self,
other: Stream,
IDs: Optional[Sequence[str]|str]=..., *,
remove: Optional[bool]=False,
exclude: Optional[bool]=False):
"""
Copy flow rates of another stream to self.
Parameters
----------
other :
Flow rates will be copied from here.
IDs :
Chemical IDs.
remove :
If True, copied chemicals will be removed from `stream`.
exclude :
If True, exclude designated chemicals when copying.
Examples
--------
Initialize streams:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2')
Copy all flows:
>>> s2.copy_flow(s1)
>>> s2.show(flow='kg/hr')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 10
Reset and copy just water flow:
>>> s2.empty()
>>> s2.copy_flow(s1, 'Water')
>>> s2.show(flow='kg/hr')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Reset and copy all flows except water:
>>> s2.empty()
>>> s2.copy_flow(s1, 'Water', exclude=True)
>>> s2.show(flow='kg/hr')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Ethanol 10
Cut and paste flows:
>>> s2.copy_flow(s1, remove=True)
>>> s2.show(flow='kg/hr')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 10
>>> s1.show()
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow: 0
Its also possible to copy flows from a multistream:
>>> s1.phases = ('g', 'l')
>>> s1.imol['g', 'Water'] = 10
>>> s2.copy_flow(s1, remove=True)
>>> s2.show()
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kmol/hr): Water 10
>>> s1.show()
MultiStream: s1
phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa
flow: 0
Copy flows except except water and remove water:
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = tmo.Stream('s2')
>>> s2.copy_flow(s1, 'Water', exclude=True, remove=True)
>>> s1.show('wt')
Stream: s1
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
>>> s2.show('wt')
Stream: s2
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Ethanol 10
"""
other_mol = other.mol
other_chemicals = other.chemicals
chemicals = self.chemicals
if IDs == ...:
if exclude: return
if chemicals is other_chemicals:
self.mol[:] = other.mol
else:
self.empty()
CASs = other_chemicals.CASs
dct = other_mol.dct
CASs = [CASs[i] for i in dct]
values = list(dct.values())
self.imol[CASs] = values
if remove:
if isinstance(other, tmo.MultiStream):
other.imol.data.clear()
else:
other_mol.clear()
else:
if exclude:
if isinstance(IDs, str):
if IDs in other_chemicals:
bad_index = other_chemicals.index(IDs)
other_index = [i for i in range(other_chemicals.size) if i != bad_index]
else:
other_index = slice()
else:
IDs = [i for i in IDs if i in other_chemicals]
bad_index = set(other_chemicals.indices(IDs))
if bad_index:
other_index = [i for i in range(other_chemicals.size) if i not in bad_index]
else:
other_index = slice()
else:
other_index = other_chemicals.get_index(IDs)
if chemicals is other_chemicals:
self.mol[other_index] = other_mol[other_index]
else:
CASs = other_chemicals.CASs
other_index = [i for i in other_index if other_mol[i] or CASs[i] in chemicals]
self.imol[tuple([CASs[i] for i in other_index])] = other_mol[other_index]
if remove:
if isinstance(other, tmo.MultiStream):
other.imol.data[:, other_index] = 0
else:
other_mol[other_index] = 0
[docs]
def copy(self, ID=None, thermo=None):
"""
Return a copy of the stream.
Examples
--------
Create a copy of a new stream:
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1_copy = s1.copy('s1_copy')
>>> s1_copy.show(flow='kg/hr')
Stream: s1_copy
phase: 'l', T: 298.15 K, P: 101325 Pa
flow (kg/hr): Water 20
Ethanol 10
Warnings
--------
Prices, and LCA characterization factors are not copied.
"""
cls = self.__class__
new = cls.__new__(cls)
new.equations = {}
new._sink = new._source = None
new.characterization_factors = {}
new._thermo = thermo or self._thermo
new._imol = self._imol.copy()
if thermo and thermo.chemicals is not self.chemicals:
new._imol.reset_chemicals(thermo.chemicals)
new._thermal_condition = self._thermal_condition.copy()
new.reset_cache()
new.price = 0
new.ID = ID
return new
__copy__ = copy
[docs]
def flow_proxy(self, ID=None):
"""
Return a new stream that shares flow rate data with this one.
See Also
--------
:obj:`~Stream.link_with`
:obj:`~Stream.proxy`
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = s1.flow_proxy()
>>> s2.mol is s1.mol
True
"""
cls = self.__class__
new = cls.__new__(cls)
new._ID = ID or ''
new._sink = new._source = None
new._price = 0
new._thermo = self._thermo
new._imol = imol = self._imol._copy_without_data()
imol.data = self._imol.data
new._thermal_condition = self._thermal_condition.copy()
new.reset_cache()
new.equations = {}
new.characterization_factors = {}
return new
[docs]
def proxy(self, ID=None):
"""
Return a new stream that shares all data with this one.
See Also
--------
:obj:`~Stream.link_with`
:obj:`~Stream.flow_proxy`
Warning
-------
Price and characterization factor data is not shared
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s2 = s1.proxy()
>>> s2.imol is s1.imol and s2.thermal_condition is s1.thermal_condition
True
"""
cls = self.__class__
new = cls.__new__(cls)
new._original = self
new._ID = ID or ''
new._sink = new._source = None
new._price = self._price
new._thermo = self._thermo
new._imol = self._imol
new._thermal_condition = self._thermal_condition
new._property_cache = self._property_cache
new._property_cache_key = self._property_cache_key
new._bubble_point_cache = self._bubble_point_cache
new._dew_point_cache = self._dew_point_cache
new.equations = self.equations
new.characterization_factors = self.characterization_factors
return new
[docs]
def empty(self):
"""Empty stream flow rates.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, units='kg/hr')
>>> s1.empty()
>>> s1.F_mol
0
"""
self._imol.data.clear()
### Equilibrium ###
@property
def vle(self) -> eq.VLE:
"""An object that can perform vapor-liquid equilibrium on the stream."""
if self.phase == 's': self.phase = 'l'
self.phases = ('g', 'l')
return self.vle
@property
def lle(self) -> eq.LLE:
"""An object that can perform liquid-liquid equilibrium on the stream."""
if self.phase not in ('l', 'L'): self.phase = 'l'
self.phases = ('L', 'l')
return self.lle
@property
def sle(self) -> eq.SLE:
"""An object that can perform solid-liquid equilibrium on the stream."""
if self.phase not in ('l', 's'): self.phase = 'l'
self.phases = ('s', 'l')
return self.sle
[docs]
def vlle(self, T, P):
"""
Estimate vapor-liquid-liquid equilibrium.
Warning
-------
This method may be as slow as 1 second.
"""
self.phases = ('L', 'g', 'l')
imol = self.imol
vle = eq.VLE(imol,
self._thermal_condition,
self._thermo,
self._bubble_point_cache,
self._dew_point_cache)
lle = eq.LLE(imol,
self._thermal_condition,
self._thermo)
data = imol.data
net_chemical_flows = data.sum(axis=0)
data.clear()
imol['l'] = net_chemical_flows
total_flow = net_chemical_flows.sum()
def f(x, done=[False]):
if done[0]: return x
data[:] = x
lle(T=T, P=P)
net_phase_flows = data.sum(axis=1, keepdims=True)
compositions = data / net_phase_flows
if (abs(compositions[0] - compositions[2]).sum() < 1e-3
or compositions[0].sum() < 1e-6
or compositions[2].sum() < 1e-6): # Perform VLE on one liquid phase
data[2] += data[0] # All flows must be in the 'l' phase for VLE
data[0] = 0.
vle(T=T, P=P)
done[0] = True
return data
else: # Perform VLE on each liquid phase
vle(T=T, P=P)
no_vapor = not data[1].any()
data[2], data[0] = data[0].copy(), data[2].copy()
vle(T=T, P=P)
done[0] = no_vapor and not data[1].any() # No VLE
return data.to_array()
data[:] = total_flow * flx.fixed_point(
f, data / total_flow, xtol=1e-3,
checkiter=False, checkconvergence=False,
convergenceiter=10
)
@property
def vle_chemicals(self) -> list[tmo.Chemical]:
"""Chemicals cabable of liquid-liquid equilibrium."""
chemicals = self.chemicals
chemicals_tuple = chemicals.tuple
indices = chemicals.get_vle_indices(self.mol.nonzero_keys())
return [chemicals_tuple[i] for i in indices]
@property
def lle_chemicals(self) -> list[tmo.Chemical]:
"""Chemicals cabable of vapor-liquid equilibrium."""
chemicals = self.chemicals
chemicals_tuple = chemicals.tuple
indices = chemicals.get_lle_indices(self.mol.nonzero_keys())
return [chemicals_tuple[i] for i in indices]
[docs]
def get_bubble_point(self, IDs: Optional[Sequence[str]]=None):
"""
Return a BubblePoint object capable of computing bubble points.
Parameters
----------
IDs :
Chemicals that participate in equilibrium. Defaults to all chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.get_bubble_point()
BubblePoint([Water, Ethanol])
"""
chemicals = self.chemicals[IDs] if IDs else self.vle_chemicals
bp = self._bubble_point_cache(chemicals, self._thermo)
return bp
[docs]
def get_dew_point(self, IDs: Optional[Sequence[str]]=None):
"""
Return a DewPoint object capable of computing dew points.
Parameters
----------
IDs :
Chemicals that participate in equilibrium. Defaults to all chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.get_dew_point()
DewPoint([Water, Ethanol])
"""
chemicals = self.chemicals[IDs] if IDs else self.vle_chemicals
dp = self._dew_point_cache(chemicals, self._thermo)
return dp
[docs]
def bubble_point_at_T(self, T: Optional[float]=None, IDs: Optional[Sequence[str]]=None):
"""
Return a BubblePointResults object with all data on the bubble point at constant temperature.
Parameters
----------
T :
Temperature [K].
IDs :
Chemicals that participate in equilibrium. Defaults to all chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.bubble_point_at_T()
BubblePointValues(T=350.00, P=76463, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.488 0.512])
"""
bp = self.get_bubble_point(IDs)
z = self.get_normalized_mol(bp.IDs)
return bp(z, T=T or self.T)
[docs]
def bubble_point_at_P(self, P: Optional[float]=None, IDs: Optional[Sequence[str]]=None):
"""
Return a BubblePointResults object with all data on the bubble point at constant pressure.
Parameters
----------
IDs :
Chemicals that participate in equilibrium. Defaults to all chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.bubble_point_at_P()
BubblePointValues(T=357.14, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.492 0.508])
"""
bp = self.get_bubble_point(IDs)
z = self.get_normalized_mol(bp.IDs)
return bp(z, P=P or self.P)
[docs]
def dew_point_at_T(self, T: Optional[float]=None, IDs: Optional[Sequence[str]]=None):
"""
Return a DewPointResults object with all data on the dew point
at constant temperature.
Parameters
----------
IDs :
Chemicals that participate in equilibrium. Defaults to all
chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.dew_point_at_T()
DewPointValues(T=350.00, P=49058, IDs=('Water', 'Ethanol'), z=[0.836 0.164], x=[0.984 0.016])
"""
dp = self.get_dew_point(IDs)
z = self.get_normalized_mol(dp.IDs)
return dp(z, T=T or self.T)
[docs]
def dew_point_at_P(self, P: Optional[float]=None, IDs: Optional[Sequence[str]]=None):
"""
Return a DewPointResults object with all data on the dew point
at constant pressure.
Parameters
----------
IDs :
Chemicals that participate in equilibrium. Defaults to all
chemicals in equilibrium.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, T=350, units='kg/hr')
>>> s1.dew_point_at_P()
DewPointValues(T=368.62, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], x=[0.983 0.017])
"""
dp = self.get_dew_point(IDs)
z = self.get_normalized_mol(dp.IDs)
return dp(z, P=P or self.P)
[docs]
def get_normalized_mol(self, IDs: Sequence[str]):
"""
Return normalized molar fractions of given chemicals. The sum of the result is always 1.
Parameters
----------
IDs :
IDs of chemicals to be normalized.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='kmol/hr')
>>> s1.get_normalized_mol(('Water', 'Ethanol'))
array([0.667, 0.333])
"""
z = self.imol[IDs]
z_sum = z.sum()
if not z_sum: raise RuntimeError(f'{repr(self)} is empty')
return z / z_sum
[docs]
def get_normalized_mass(self, IDs: Sequence[str]):
"""
Return normalized mass fractions of given chemicals. The sum of the result is always 1.
Parameters
----------
IDs :
IDs of chemicals to be normalized.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='kg/hr')
>>> s1.get_normalized_mass(('Water', 'Ethanol'))
array([0.667, 0.333])
"""
z = self.imass[IDs]
z_sum = z.sum()
if not z_sum: raise RuntimeError(f'{repr(self)} is empty')
return z / z_sum
[docs]
def get_normalized_vol(self, IDs: Sequence[str]):
"""
Return normalized mass fractions of given chemicals. The sum of the result is always 1.
Parameters
----------
IDs :
IDs of chemicals to be normalized.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='m3/hr')
>>> s1.get_normalized_vol(('Water', 'Ethanol'))
array([0.667, 0.333])
"""
z = self.ivol[IDs]
z_sum = z.sum()
if not z_sum: raise RuntimeError(f'{repr(self)} is empty')
return z / z_sum
[docs]
def get_molar_fraction(self, IDs: Sequence[str]):
"""
Return molar fraction of given chemicals.
Parameters
----------
IDs :
IDs of chemicals.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='kmol/hr')
>>> s1.get_molar_fraction(('Water', 'Ethanol'))
array([0.5 , 0.25])
"""
F_mol = self.F_mol
return self.imol[IDs] / F_mol if F_mol else 0.
get_molar_composition = get_molar_fraction
[docs]
def get_mass_fraction(self, IDs: Sequence[str]):
"""
Return mass fraction of given chemicals.
Parameters
----------
IDs :
IDs of chemicals.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='kg/hr')
>>> s1.get_mass_fraction(('Water', 'Ethanol'))
array([0.5 , 0.25])
"""
F_mass = self.F_mass
return self.imass[IDs] / F_mass if F_mass else 0.
get_mass_composition = get_mass_fraction
[docs]
def get_volumetric_fraction(self, IDs: Sequence[str]):
"""
Return volumetric fraction of given chemicals.
Parameters
----------
IDs :
IDs of chemicals.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='m3/hr')
>>> s1.get_volumetric_fraction(('Water', 'Ethanol'))
array([0.5 , 0.25])
"""
F_vol = self.F_vol
return self.ivol[IDs] / F_vol if F_vol else 0.
get_volumetric_composition = get_volumetric_fraction
[docs]
def get_concentration(self, IDs: Sequence[str], units: Optional[str]=None):
"""
Return concentration of given chemicals.
Parameters
----------
IDs :
IDs of chemicals.
units :
Units of measure. Defaults to kmol/m3.
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True)
>>> s1 = tmo.Stream('s1', Water=20, Ethanol=10, Methanol=10, units='m3/hr')
>>> s1.get_concentration(['Water', 'Ethanol']) # kg/m3
array([27.673, 4.261])
>>> s1.get_concentration(['Water', 'Ethanol'], 'g/L')
array([498.532, 196.291])
"""
F_vol = self.F_vol
if F_vol == 0.: return 0.
if units is None:
return self.imol[IDs] / F_vol
else:
num, denum = units.split('/')
return self.get_flow(num+'/hr', IDs) / self.get_total_flow(denum+'/hr')
@property
def P_vapor(self) -> float:
"""Vapor pressure of liquid."""
chemicals = self.vle_chemicals
F_l = eq.LiquidFugacities(chemicals, self.thermo)
IDs = tuple([i.ID for i in chemicals])
x = self.get_molar_fraction(IDs)
if x.sum() < 1e-12: return 0
return F_l(x, self.T).sum()
[docs]
def receive_vent(self, other, energy_balance=True, ideal=False):
"""
Receive vapors from another stream by vapor-liquid equilibrium between
a gas and liquid stream assuming only a small amount of chemicals
in vapor-liquid equilibrium is present
Examples
--------
The energy balance is performed by default:
>>> import thermosteam as tmo
>>> chemicals = tmo.Chemicals(['Water', 'Ethanol', 'Methanol', tmo.Chemical('N2', phase='g')], cache=True)
>>> tmo.settings.set_thermo(chemicals)
>>> s1 = tmo.Stream('s1', N2=20, units='m3/hr', phase='g', T=330)
>>> s2 = tmo.Stream('s2', Water=10, Ethanol=2, T=330)
>>> s1.receive_vent(s2)
>>> s1.show(flow='kmol/hr')
Stream: s1
phase: 'g', T: 323.12 K, P: 101325 Pa
flow (kmol/hr): Water 0.0799
Ethanol 0.0887
N2 0.739
Set energy balance to false to receive vent isothermally:
>>> import thermosteam as tmo
>>> chemicals = tmo.Chemicals(['Water', 'Ethanol', 'Methanol', tmo.Chemical('N2', phase='g')], cache=True)
>>> tmo.settings.set_thermo(chemicals)
>>> s1 = tmo.Stream('s1', N2=20, units='m3/hr', phase='g', T=330)
>>> s2 = tmo.Stream('s2', Water=10, Ethanol=2, T=330)
>>> s1.receive_vent(s2, energy_balance=False)
>>> s1.show(flow='kmol/hr')
Stream: s1
phase: 'g', T: 330 K, P: 101325 Pa
flow (kmol/hr): Water 0.112
Ethanol 0.123
N2 0.739
"""
assert self.phase == 'g', 'stream must be a gas to receive vent'
thermo = self.thermo.ideal() if ideal else self.thermo
T = self.T
P = self.P
ms = tmo.Stream(None, T=T, P=P, thermo=thermo)
ms.mix_from([self, other], energy_balance=False)
if energy_balance: ms.H = H = self.H + other.H
ms.vle._setup()
vapor = ms['g']
liquid = ms['l']
for chemical in ms.chemicals:
try: Psat = chemical.Psat(T)
except: continue
ID = chemical.ID
if Psat < P:
liquid.imol[ID] = ms.imol[ID]
vapor.imol[ID] = 0.
else:
vapor.imol[ID] = ms.imol[ID]
liquid.imol[ID] = 0.
chemicals = ms.vle_chemicals
F_l = eq.LiquidFugacities(chemicals, thermo)
IDs = tuple([i.ID for i in chemicals])
x = other.get_molar_fraction(IDs)
F_mol_vapor = vapor.F_mol
mol = liquid.imol[IDs] + vapor.imol[IDs]
if energy_balance:
def equilibrium_approximation(T):
f_l = F_l(x, T)
y = f_l / P
mol_v = F_mol_vapor * y
vapor.imol[IDs] = mol_v
liquid.imol[IDs] = mol - mol_v
index = liquid.mol.negative_index()
vapor.mol[index] += liquid.mol[index]
liquid.mol[index] = 0
ms.H = H
return ms.T
flx.wegstein(equilibrium_approximation, T, xtol=1e-4, maxiter=100)
else:
f_l = F_l(x, T)
y = f_l / P
mol_v = F_mol_vapor * y
vapor.imol[IDs] = mol_v
liquid.imol[IDs] = mol - mol_v
index = liquid.mol.negative_index()
vapor.mol[index] += liquid.mol[index]
liquid.mol[index] = 0
self.copy_like(vapor)
other.copy_like(liquid)
self.T = other.T = ms.T
### Casting ###
@property
def phases(self) -> tuple[str, ...]:
"""All phases present."""
return (self.phase,)
@phases.setter
def phases(self, phases):
phases = set(phases)
if len(phases) == 1:
self.phase, = phases
else:
self.__class__ = tmo.MultiStream
self._imol = self._imol.to_material_indexer(phases)
self._streams = {}
self._vle_cache = eq.VLECache(self._imol,
self._thermal_condition,
self._thermo,
self._bubble_point_cache,
self._dew_point_cache)
self._lle_cache = eq.LLECache(self._imol,
self._thermal_condition,
self._thermo)
self._sle_cache = eq.SLECache(self._imol,
self._thermal_condition,
self._thermo)
[docs]
def reduce_phases(self):
"""Remove empty phases."""
### Representation ###
def _info_phaseTP(self, phase, units, notation):
T_units = units['T']
P_units = units['P']
T = UofM.convert(self.T, 'K', T_units)
P = UofM.convert(self.P, 'Pa', P_units)
s = '' if isinstance(phase, str) else 's'
return f"phase{s}: {repr(phase)}, T: {T:{notation['T']}} {T_units}, P: {P:{notation['P']}} {P_units}\n"
def _translate_layout(self, layout, flow, composition, N, sort):
if layout:
if layout[-1] == 's':
sort = True
layout = layout[:-1]
if layout[0] == 'c':
composition = True
layout = layout[1:]
if layout.startswith('wt'):
flow = 'kg/hr'
layout = layout[2:]
elif layout.startswith('mol'):
flow = 'kmol/hr'
layout = layout[3:]
elif layout.startswith('vol'):
flow = 'm3/hr'
layout = layout[3:]
elif layout.isdigit():
flow = 'kmol/hr'
else:
raise ValueError(
"`layout` must have the form "
"{'c' or ''}{'wt', 'mol' or 'vol'}{# or ''}{'s' or ''};"
"for example: 'cwt100s' corresponds to compostion=True, "
"flow='kg/hr', N=100, sort=True"
)
if layout.isdigit():
N = int(layout)
return flow, composition, N, sort
def get_display_units_and_notation(self, **kwargs):
display_units = self.display_units
display_notation = self.display_notation
units_dct = {}
notation_dct = {}
for name, value in kwargs.items():
units, notation = UofM.parse_units_notation(value)
units_dct[name] = getattr(display_units, name) if units is None else units
notation_dct[name] = getattr(display_notation, name) if notation is None else notation
return units_dct, notation_dct
def _info_str(self, units, notation, composition, N_max, all_IDs, indexer, factor):
basic_info = self._basic_info()
basic_info += self._info_phaseTP(self.phase, units, notation)
flow_units = units['flow']
flow_notation = notation['flow']
if N_max == 0:
return basic_info[:-1]
N_IDs = len(all_IDs)
if N_IDs == 0:
return basic_info + 'flow: 0'
# Remaining lines (all flow rates)
flow_array = factor * indexer[all_IDs]
if composition:
total_flow = flow_array.sum()
beginning = "composition (%): "
new_line = '\n' + len(beginning) * ' '
flow_array = 100 * flow_array/total_flow
else:
beginning = f'flow ({flow_units}): '
new_line = '\n' + len(beginning) * ' '
flow_rates = ''
too_many_chemicals = N_IDs > N_max
if not too_many_chemicals: N_max = N_IDs
lengths = [len(i) for i in all_IDs[:N_max]]
maxlen = max(lengths) + 2
for i in range(N_max):
spaces = ' ' * (maxlen - lengths[i])
if i: flow_rates += new_line
flow_rates += all_IDs[i] + spaces + f'{flow_array[i]:{flow_notation}}'
if too_many_chemicals:
spaces = ' ' * (maxlen - 3)
flow_rates += new_line + '...' + spaces + f'{flow_array[N_max:].sum():{flow_notation}}'
if composition:
dashes = '-' * (maxlen - 2)
flow_rates += f"{new_line}{dashes} {total_flow:{flow_notation}} {flow_units}"
return (basic_info
+ beginning
+ flow_rates)
def _info_df(self, units, notation, composition, N_max, all_IDs, indexer, factor):
if not all_IDs:
return pd.DataFrame([0], columns=[self.ID.replace('_', ' ')], index=['Flow'])
T_units = units['T']
P_units = units['P']
flow_units = units['flow']
T_notation = notation['T']
P_notation = notation['P']
flow_notation = notation['flow']
T = UofM.convert(self.T, 'K', T_units)
P = UofM.convert(self.P, 'Pa', P_units)
data = []
index = []
index.append((f"Temperature [{T_units}]", ''))
data.append(f"{T:{T_notation}}")
index.append((f"Pressure [{P_units}]", ''))
data.append(f"{P:{P_notation}}")
for phase in self.phases:
if indexer.data.ndim == 2:
flow_array = factor * indexer[phase, all_IDs]
else:
flow_array = factor * indexer[all_IDs]
phase = valid_phases[phase]
if phase.islower(): phase = phase.capitalize()
if composition:
total_flow = flow_array.sum()
index.append((f"{phase} [{flow_units}]", ''))
data.append(f"{total_flow:{flow_notation}}")
comp_array = 100 * flow_array / total_flow
for i, (ID, comp) in enumerate(zip(all_IDs, comp_array)):
if not comp: continue
if i >= N_max:
index.append(("Composition [%]", '(remainder)'))
data.append(f"{comp_array[N_max:].sum():{flow_notation}}")
break
else:
index.append(("Composition [%]", ID))
data.append(f"{comp:{flow_notation}}")
else:
for i, (ID, flow) in enumerate(zip(all_IDs, flow_array)):
if not flow: continue
if i >= N_max:
index.append((f"{phase} [{flow_units}]", '(remainder)'))
data.append(f"{flow_array[N_max:].sum():{flow_notation}}")
break
else:
index.append((f"{phase} [{flow_units}]", ID))
data.append(f"{flow:{flow_notation}}")
return pd.DataFrame(data, columns=[self.ID.replace('_', ' ')],
index=pd.MultiIndex.from_tuples(index))
def _info(self, layout, T, P, flow, composition, N, IDs, sort=None, df=False):
"""Return string with all specifications."""
units, notation = self.get_display_units_and_notation(T=T, P=P, flow=flow)
units['flow'], composition, N, sort = self._translate_layout(layout, units['flow'], composition, N, sort)
display_units = self.display_units
N_max = display_units.N if N is None else N
composition = display_units.composition if composition is None else composition
sort = display_units.sort if sort is None else sort
name, factor = self._get_flow_name_and_factor(units['flow'])
indexer = getattr(self, 'i' + name)
if not IDs:
IDs = self.chemicals.IDs
data = getattr(self, name)
else:
data = indexer[IDs]
IDs, data = nonzeros(IDs, data)
if sort:
index = sorted(range(len(data)), key=lambda x: data[x], reverse=True)
IDs = [IDs[i] for i in index]
IDs = tuple(IDs)
return (self._info_df if df else self._info_str)(
units, notation, composition, N_max, IDs, indexer, factor,
)
def _get_tooltip_string(self, format, full):
if format not in ('html', 'svg'): return ''
if self.isempty():
tooltip = '(empty)'
elif format == 'html' and full:
df = self._info(None, None, None, None, None, None, None, None, df=True)
tooltip = (
" " + # makes sure graphviz does not try to parse the string as HTML
df.to_html(justify='unset'). # unset makes sure that table header style can be overwritten in CSS
replace("\n", "").replace(" ", "") # makes sure tippy.js does not add any whitespaces
)
else:
newline = '<br>' if format == 'html' else '\n'
display_units = self.display_units
T_units = display_units.T
P_units = display_units.P
flow_units = display_units.flow
T = UofM.convert(self.T, 'K', T_units)
P = UofM.convert(self.P, 'Pa', P_units)
display_notation = self.display_notation
T_notation = display_notation.T
P_notation = display_notation.P
flow_notation = display_notation.flow
tooltip = (
f"Temperature: {T:{T_notation}} {T_units}{newline}"
f"Pressure: {P:{P_notation}} {P_units}"
)
for phase in self.phases:
stream = self[phase] if self.imol.data.ndim == 2 else self
flow = stream.get_total_flow(flow_units)
phase = valid_phases[phase]
if phase.islower(): phase = phase.capitalize()
tooltip += f"{newline}{phase} flow: {flow:{flow_notation}} {flow_units}"
if format == 'html':
tooltip = " " + tooltip
return tooltip
[docs]
def show(self,
layout: Optional[str]=None,
T: Optional[str]=None,
P: Optional[str]=None,
flow: Optional[str]=None,
composition: Optional[bool]=None,
N: Optional[int]=None,
IDs: Optional[Sequence[str]]=None,
sort: Optional[bool]=None,
df: Optional[bool]=None):
"""
Print all specifications.
Parameters
----------
layout :
Convenience paramater for passing `flow`, `composition`, and `N`.
Must have the form {'c' or ''}{'wt', 'mol' or 'vol'}{# or ''}.
For example: 'cwt100' corresponds to compostion=True, flow='kg/hr',
and N=100.
T :
Temperature units.
P :
Pressure units.
flow :
Flow rate units.
composition :
Whether to show composition.
N :
Number of compounds to display.
IDs :
IDs of compounds to display. Defaults to all chemicals.
sort :
Whether to sort flows in descending order.
df :
Whether to return a pandas DataFrame.
Examples
--------
Show a stream's composition by weight for only the top 2 chemicals
with the highest mass fractions:
>>> import biosteam as bst
>>> bst.settings.set_thermo(['Water', 'Ethanol', 'Methanol', 'Propanol'])
>>> stream = bst.Stream('stream', Water=0.5, Ethanol=1.5, Methanol=0.2, Propanol=0.3, units='kg/hr')
>>> stream.show('cwt2s') # Alternatively: stream.show(composition=True, flow='kg/hr', N=2, sort=True)
Stream: stream
phase: 'l', T: 298.15 K, P: 101325 Pa
composition (%): Ethanol 60
Water 20
... 20
------- 2.5 kg/hr
"""
print(self._info(layout, T, P, flow, composition, N, IDs, sort, df))
_ipython_display_ = show
[docs]
def print(self, units: Optional[str]=None):
"""
Print in a format that you can use recreate the stream.
Parameters
----------
units :
Units of measure for material flow rates. Defaults to 'kmol/hr'
Examples
--------
>>> import thermosteam as tmo
>>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True)
>>> s1 = tmo.Stream(ID='s1',
... Water=20, Ethanol=10, units='kg/hr',
... T=298.15, P=101325, phase='l')
>>> s1.print(units='kg/hr')
Stream(ID='s1', phase='l', T=298.15, P=101325, Water=20, Ethanol=10, units='kg/hr')
>>> s1.print() # Units default to kmol/hr
Stream(ID='s1', phase='l', T=298.15, P=101325, Water=1.11, Ethanol=0.2171, units='kmol/hr')
"""
if not units:
units = 'kmol/hr'
flow = self.mol
else:
flow = self.get_flow(units)
chemical_flows = utils.repr_IDs_data(self.chemicals.IDs, flow)
price = utils.repr_kwarg('price', self.price)
print(f"{type(self).__name__}(ID={repr(self.ID)}, phase={repr(self.phase)}, T={self.T:.2f}, "
f"P={self.P:.6g}{price}{chemical_flows}, units={repr(units)})")
# Convinience math methods for scripting
def __add__(self, other):
return Stream.sum([self, other])
def __radd__(self, other):
return Stream.sum([self, other])
def __iadd__(self, other):
self.mix_from([self, other])
return self
def __isub__(self, other):
self.separate_out(other)
return self
def __neg__(self):
new = self.copy()
new._imol.data *= -1
return new
def __mul__(self, other):
new = self.copy()
new._imol.data *= other
return new
def __rmul__(self, other):
new = self.copy()
new._imol.data *= other
return new
def __truediv__(self, other):
new = self.copy()
new._imol.data /= other
return new
def __imul__(self, other):
self._imol.data *= other
return self
def __itruediv__(self, other):
self._imol.data /= other
return self