Source code for thermosteam._multi_stream

# -*- 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
from ._thermo import Thermo
from ._stream import Stream
from ._thermal_condition import ThermalCondition
from .indexer import MolarFlowIndexer
from ._phase import phase_tuple
from . import equilibrium as eq
from . import utils
from .indexer import nonzeros
import numpy as np
from typing import TYPE_CHECKING
if TYPE_CHECKING:
    from numpy.typing import NDArray
    from typing import Optional, Sequence, Dict, Tuple

__all__ = ('MultiStream', )

def get_phase_fraction(stream, phases):
    all_phases = stream.phases
    phase_fraction = 0.
    F_mol = stream.F_mol
    imol = stream.imol
    if not F_mol: return 0.
    for phase in phases:
        if phase in all_phases:
            phase_fraction += imol[phase].sum() 
    return phase_fraction / F_mol

[docs] @utils.registered_franchise(Stream) class MultiStream(Stream): """ Create a MultiStream object that defines material flow rates for multiple phases 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 `phases` by row and chemical IDs by column. T : Temperature [K]. Defaults to 298.15. P : Pressure [Pa]. Defaults to 101325. phases : Tuple denoting the phases present. Defaults to ('g', 'l'). 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 : Thermodynamic equilibrium package. Defaults to `thermosteam.settings.get_thermo()`. vlle : Whether to run rigorous phase equilibrium to determine phases. Defaults to False. **phase_flow : tuple[str, float] phase-(ID, flow) pairs. Examples -------- Before creating streams, first set the chemicals: >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) Create a multi phase stream, defining the thermodynamic condition and flow rates: >>> s1 = tmo.MultiStream(ID='s1',T=298.15, P=101325, ... l=[('Water', 20), ('Ethanol', 10)], units='kg/hr') >>> s1.show(flow='kg/hr') # Use the show method to select units of display MultiStream: s1 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Ethanol 10 The temperature and pressure are stored as attributes: >>> (s1.T, s1.P) (298.15, 101325.0) Unlike Stream objects, the `mol` attribute does not store data, it simply returns the total flow rate of each chemical. Setting an element of the array raises an error to prevent the wrong assumption that the data is linked: >>> s1.mol sparse([1.11 , 0.217]) >>> s1.mol[0] = 1 Traceback (most recent call last): ValueError: assignment destination is read-only All flow rates are stored in the `imol` attribute: >>> s1.imol.show() # Molar flow rates [kmol/hr] MolarFlowIndexer (kmol/hr): (l) Water 1.11 Ethanol 0.2171 >>> # Index a single chemical in the liquid phase >>> s1.imol['l', 'Water'] 1.1101 >>> # Index multiple chemicals in the liquid phase >>> s1.imol['l', ('Ethanol', 'Water')] array([0.217, 1.11 ]) >>> # Index the vapor phase >>> s1.imol['g'] sparse([0., 0.]) >>> # Index flow of chemicals summed across all phases >>> s1.imol['Ethanol', 'Water'] array([0.217, 1.11 ]) Note that overall chemical flows in MultiStream objects cannot be set like with Stream objects: >>> # s1.imol['Ethanol', 'Water'] = [1, 0] Traceback (most recent call last): IndexError: multiple phases present; must include phase key to set chemical data Chemical flows must be set by phase: >>> s1.imol['l', ('Ethanol', 'Water')] = [1, 0] The most convinient way to get and set flow rates is through the `get_flow` and `set_flow` methods: >>> # Set flow >>> key = ('l', 'Water') >>> s1.set_flow(1, 'gpm', key) >>> s1.get_flow('gpm', key) 1.0 >>> # Set multiple flows >>> key = ('l', ('Ethanol', 'Water')) >>> s1.set_flow([10, 20], 'kg/hr', key) >>> s1.get_flow('kg/hr', key) array([10., 20.]) Chemical flows across all phases can be retrieved if no phase is given: >>> s1.get_flow('kg/hr', ('Ethanol', 'Water')) array([10., 20.]) However, setting chemical data requires the phase to be specified: >>> s1.set_flow([10, 20], 'kg/hr', ('Ethanol', 'Water')) Traceback (most recent call last): IndexError: multiple phases present; must include phase key to set chemical data Note that for both Stream and MultiStream objects, `mol`, `imol`, and `get_flow` return chemical flows across all phases when given only chemical IDs. Vapor-liquid equilibrium can be performed by setting 2 degrees of freedom from the following list: * T - Temperature [K] * P - Pressure [Pa] * V - Vapor fraction * H - Enthalpy [kJ/hr] >>> s1.vle(P=101325, T=365) Each phase can be accessed separately too: >>> s1['l'].show() Stream: phase: 'l', T: 365 K, P: 101325 Pa flow (kmol/hr): Water 0.617 Ethanol 0.0238 >>> s1['g'].show() Stream: phase: 'g', T: 365 K, P: 101325 Pa flow (kmol/hr): Water 0.493 Ethanol 0.193 Note that the phase cannot be changed: >>> s1['g'].phase = 'l' Traceback (most recent call last): AttributeError: phase is locked """ __slots__ = () def __init__(self, ID: Optional[str]="", flow: Optional[Sequence]=(), T: Optional[float]=298.15, P: Optional[float]=101325., phases: Optional[Sequence[str]]=None, 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, **phase_flows: Tuple[str, float]): self.characterization_factors = {} if characterization_factors is None else {} self._thermal_condition = ThermalCondition(T, P) thermo = self._load_thermo(thermo) chemicals = thermo.chemicals self.price = price phases = set(phase_flows).union(['l', 'g']) if phases is None else phases if units: name, factor = self._get_flow_name_and_factor(units) if name == 'mass': group_wt_compositions = chemicals._group_wt_compositions for phase, chemical_flows in phase_flows.items(): new_chemical_flows = [] for item in chemical_flows: cID, value = item if cID in group_wt_compositions: compositions = group_wt_compositions[cID] chemical_group = chemicals[cID] for i in range(len(chemical_group)): item = (chemical_group[i]._ID, value * compositions[i]) new_chemical_flows.append(item) else: new_chemical_flows.append(item) phase_flows[phase] = new_chemical_flows elif name == 'vol': group_wt_compositions = chemicals._group_wt_compositions for chemical_flows in phase_flows.values(): for item in chemical_flows: cID, value = item if cID in group_wt_compositions: raise ValueError(f"cannot set volumetric flow by chemical group '{i}'") self._init_indexer(flow, phases, chemicals, phase_flows) flow = getattr(self, 'i' + name) material_data = self._imol.data / factor if total_flow: material_data *= total_flow / material_data.sum() flow.data[:] = material_data else: self._init_indexer(flow, phases, chemicals, phase_flows) if total_flow: self._imol.data *= total_flow / self.F_mol self._sink = self._source = None self.reset_cache() self._register(ID) if vlle: self.vlle(T, P) @classmethod def from_streams(cls, streams, thermo=None): if not streams: raise ValueError('at least one stream must be passed') self = cls.__new__(cls) self._streams = streams_by_phase = {i.phase: i for i in streams} phases = phase_tuple(streams_by_phase) N_streams = len(streams) if len(phases) != N_streams: raise ValueError('each stream must have a different phase') base, *others = streams self.characterization_factors = {} self._thermal_condition = base._thermal_condition for i in others: i._thermal_condition = base._thermal_condition self._load_thermo(thermo or base.thermo) self.price = 0 self._imol = MolarFlowIndexer.from_data( [streams_by_phase[i]._imol.data for i in phases], phases, chemicals=base.chemicals ) self._sink = self._source = None self.reset_cache() self._register(None) return self
[docs] def reset_flow(self, total_flow=None, units=None, phases=None, **phase_flows): """ Convinience method for resetting flow rate data. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 1)]) >>> s1.reset_flow(g=[('Ethanol', 1)], phases='lgs', units='kg/hr', total_flow=2) >>> s1.show('cwt') MultiStream: s1 phases: ('g', 'l', 's'), T: 298.15 K, P: 101325 Pa composition (%): (g) Ethanol 100 ------- 2 kg/hr """ imol = self._imol imol.empty() self.phases = set(phase_flows).union(['l', 'g']) if phases is None else phases if phase_flows: for phase, data in phase_flows.items(): keys, values = zip(*data) self.set_flow(values, units, (phase, keys)) if total_flow: self.set_total_flow(total_flow, units)
def _init_indexer(self, flow, phases, chemicals, phase_flows): if flow == (): if phase_flows: imol = MolarFlowIndexer(phases, chemicals=chemicals, **phase_flows) else: imol = MolarFlowIndexer.blank(phases, chemicals) else: assert not phase_flows, ("may specify either 'flow' or " "'phase_flows', but not both") if isinstance(flow, MolarFlowIndexer): imol = flow else: imol = MolarFlowIndexer.from_data(flow, phases, chemicals) self._imol = imol 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 = [i.dct for i in composition.rows] if nophase: literal = (thermal_condition._T, thermal_condition._P) else: literal = (imol._phases, 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.get(name) return value * total if flow else value else: property_cache.clear() self._property_cache_key = (literal, [i.copy() for i in composition_key]) if nophase: calculate = getattr(self.mixture, name) self._property_cache[name] = value = calculate( composition.sum(axis=0), *self.thermal_condition ) else: calculate = getattr(self.mixture, 'x' + name) self._property_cache[name] = value = calculate( zip(imol._phases, composition), *self.thermal_condition ) return value * total if flow else value
[docs] def reset_cache(self): """Reset cache regarding equilibrium methods.""" super().reset_cache() if hasattr(self, '_streams'): for i in self._streams.values(): i.reset_cache() else: 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)
def __getitem__(self, phase): streams = self._streams if phase in streams: stream = streams[phase] else: stream = Stream.__new__(Stream) stream._ID = stream._sink = stream._source = None stream._imol = self._imol.get_phase(phase) stream._thermal_condition = self._thermal_condition stream._thermo = self._thermo stream._bubble_point_cache = self._bubble_point_cache stream._dew_point_cache = self._dew_point_cache stream._property_cache = {} stream.characterization_factors = {} stream._property_cache_key = None, None streams[phase] = stream return stream def __iter__(self): for i in self.phases: yield self[i] def __len__(self): return len(self.phases) ### Property getters ###
[docs] def get_flow(self, units: str, key=...): """ Return an array of flow rates in requested units. Parameters ---------- units : Units of measure. key : Index key as (phase, IDs), phase, or IDs where: * phase is a str, ellipsis, or missing. * IDs is a str, Sequence[str], ellipisis, or missing. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10)], units='kg/hr') >>> s1.get_flow('kg/hr', ('l', 'Water')) 20.0 >>> s1.get_flow('kg/hr') sparse([20., 10.]) """ 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=...): """ Set flow rates in given units. Parameters ---------- data : Flow rate data. units : Units of measure. key : Index key as (phase, IDs), phase, or IDs where: * phase is a str, ellipsis, or missing. * IDs is a str, Sequence[str], ellipisis, or missing. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10)], units='kg/hr') >>> s1.set_flow(10, 'kg/hr', ('l', 'Water')) >>> s1.get_flow('kg/hr', ('l', '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
### Stream data ### @property def phases(self) -> tuple[str, ...]: """All phases avaiable.""" return self._imol._phases @phases.setter def phases(self, phases): phases = set(phases) if len(phases) == 1: self.phase, = phases phases = phase_tuple(phases) if phases != self.phases: self._imol = self._imol.to_material_indexer(phases) self.reset_cache() ### Flow properties ### @property def mol(self) -> NDArray[float]: """Chemical molar flow rates (total of all phases).""" mol = self._imol.data.sum(0) mol.read_only = True return mol @property def mass(self) -> NDArray[float]: """Chemical mass flow rates (total of all phases).""" mass = self.mol * self.chemicals.MW mass.read_only = True return mass @property def vol(self) -> NDArray[float]: """Chemical volumetric flow rates (total of all phases).""" vol = self.ivol.data.sum(0) vol.read_only = True return vol ### Net flow properties ### @property def H(self) -> float: """Enthalpy flow rate [kJ/hr].""" return self._get_property('H', True) @H.setter def H(self, H): if not H and self.isempty(): return self.T = self.mixture.xsolve_T_at_HP( self._imol, H, *self._thermal_condition ) @property def h(self) -> float: """Specific enthalpy in kJ/kmol.""" return self._get_property('H') @h.setter def h(self, h: float): if not h and self.isempty(): return self.T = self.mixture.xsolve_T_at_HP( self._imol.iter_composition(), h, *self._thermal_condition ) @property def S(self) -> float: """Absolute entropy flow rate [kJ/hr].""" return self._get_property('S', True) @S.setter def S(self, S): if not S and self.isempty(): return self.T = self.mixture.xsolve_T_at_SP( self._imol, S, *self._thermal_condition ) ### Composition properties ### @property def vapor_fraction(self) -> float: """Molar vapor fraction.""" return self.imol['g'].sum() / F_mol if 'g' in self.phases and (F_mol:=self.F_mol) != 0. else 0. @property def liquid_fraction(self) -> float: """Molar liquid fraction.""" return get_phase_fraction(self, 'lL') @property def solid_fraction(self) -> float: """Molar solid fraction.""" return get_phase_fraction(self, 'sS') ### Methods ###
[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') >>> s.phases = ('l', 'g') >>> 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') MultiStream: s1 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 10 Ethanol 1 >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 10 Ethanol 9 """ phases = self.phases if energy_balance or isinstance(s1, MultiStream) or isinstance(s2, MultiStream): s1.phases = phases s2.phases = phases for phase in phases: self[phase].split_to(s1[phase], s2[phase], split) else: Stream.split_to(self, s1, s2, split) return 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
[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.MultiStream('s1', l=[('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') MultiStream: s1 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) 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.MultiStream('s1', l=[('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') MultiStream: s1 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 2 """ self._imol.copy_like(other._imol) self._thermal_condition.copy_like(other._thermal_condition)
[docs] def copy_flow(self, other: Stream, phase: Optional[Sequence[str]|str]=..., 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. Defaults to all chemicals. remove : If True, copied chemicals will be removed from `stream`. exclude : If True, exclude designated chemicals when copying. Notes ----- Works just like <Stream>.copy_flow, but the phase must be specified. Examples -------- Initialize streams: >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10)], units='kg/hr') >>> s2 = tmo.MultiStream('s2') Copy all flows: >>> s2.copy_flow(s1) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Ethanol 10 Reset and copy just water flow: >>> s2.empty() >>> s2.copy_flow(s1, IDs='Water') >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Reset and copy all flows except water: >>> s2.empty() >>> s2.copy_flow(s1, IDs='Water', exclude=True) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Ethanol 10 Cut and paste flows: >>> s2.copy_flow(s1, remove=True) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Ethanol 10 >>> s1.show() MultiStream: s1 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow: 0 The other stream can also be a single phase stream (doesn't have to be a MultiStream object): 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.MultiStream('s2') Copy all flows: >>> s2.copy_flow(s1) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Ethanol 10 Reset and copy just water flow: >>> s2.empty() >>> s2.copy_flow(s1, IDs='Water') >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Reset and copy all flows except water: >>> s2.empty() >>> s2.copy_flow(s1, IDs='Water', exclude=True) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Ethanol 10 Cut and paste flows: >>> s2.copy_flow(s1, remove=True) >>> s2.show(flow='kg/hr') MultiStream: s2 phases: ('g', 'l'), T: 298.15 K, P: 101325 Pa flow (kg/hr): (l) Water 20 Ethanol 10 >>> s1.show() Stream: s1 phase: 'l', T: 298.15 K, P: 101325 Pa flow: 0 """ if self.chemicals is not other.chemicals and self.chemicals.IDs != other.chemicals.IDs: raise ValueError('other stream must have the same chemicals defined to copy flow') IDs_index = self.chemicals.get_index(IDs) phase_index = self.imol.get_phase_index(phase) data = self.imol.data other_data = other.imol.data multiphase = other_data.ndim == 2 if exclude: data = self.imol.data other_data = other.imol.data original_data = data.copy() if multiphase: data[:] = other_data data[phase_index, IDs_index] = original_data[phase_index, IDs_index] if remove: excluded_data = other_data[phase_index, IDs_index] other_data[:] = 0. other_data[phase_index, IDs_index] = excluded_data else: other_phase_index = self.imol.get_phase_index(other.phase) data[other_phase_index, :] = other_data data[phase_index, IDs_index] = original_data[phase_index, IDs_index] if remove and (phase is ... or phase_index == other_phase_index): excluded_data = other_data[IDs_index] other_data[:] = 0. other_data[IDs_index] = excluded_data elif multiphase: data[phase_index, IDs_index] = other_data[phase_index, IDs_index] if remove: other_data[phase_index, IDs_index] = 0. else: data[:] = 0. other_phase_index = self.imol.get_phase_index(other.phase) if phase is ... or phase_index == other_phase_index: data[other_phase_index, IDs_index] = other_data[IDs_index] if remove: other_data[IDs_index] = 0.
[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.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='kmol/hr') >>> s1.get_normalized_mol(('Water', 'Ethanol')) array([0.667, 0.333]) """ z = self.imol[..., IDs].sum(0) z /= z.sum() return z
[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.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='m3/hr') >>> s1.get_normalized_vol(('Water', 'Ethanol')) array([0.667, 0.333]) """ z = self.ivol[..., IDs].sum(0) z /= z.sum() return z
[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.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='kg/hr') >>> s1.get_normalized_mass(('Water', 'Ethanol')) array([0.667, 0.333]) """ z = self.imass[..., IDs].sum(0) z /= z.sum() return z
[docs] def get_molar_composition(self, IDs: Sequence[str]): """ Return molar composition of given chemicals. Parameters ---------- IDs : IDs of chemicals. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='kmol/hr') >>> s1.get_molar_composition(('Water', 'Ethanol')) array([0.5 , 0.25]) """ return self.imol[..., IDs].sum(0)/self.F_mol
[docs] def get_mass_composition(self, IDs: Sequence[str]): """ Return mass composition of given chemicals. Parameters ---------- IDs : IDs of chemicals. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='kg/hr') >>> s1.get_mass_composition(('Water', 'Ethanol')) array([0.5 , 0.25]) """ return self.imass[..., IDs].sum(0)/self.F_mass
[docs] def get_volumetric_composition(self, IDs: Sequence[str]): """ Return volumetric composition of given chemicals. Parameters ---------- IDs : IDs of chemicals. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='m3/hr') >>> s1.get_volumetric_composition(('Water', 'Ethanol')) array([0.5 , 0.25]) """ return self.ivol[..., IDs].sum(0)/self.F_vol
[docs] def get_concentration(self, phase: str, IDs: Sequence[str]|str, units: Optional[str]=None): """ Return concentration of given chemicals in kmol/m3. Parameters ---------- phase : IDs : IDs of chemicals. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol', 'Methanol'], cache=True) >>> s1 = tmo.MultiStream('s1', l=[('Water', 20), ('Ethanol', 10), ('Methanol', 10)], units='m3/hr') >>> s1.get_concentration('l', ('Water', 'Ethanol')) array([27.673, 4.261]) >>> s1.get_concentration('l', ('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', (phase, IDs)) / self.get_total_flow(denum + '/hr') return self.imol[phase, IDs] / self.F_vol
### Equilibrium ### # @property # def equilibrium(self): # """[Equilibrium] An object that can perform equilibrium on the stream.""" # phases = self.phases # if phases == ('g', 'l'): # cache = self._vle_cache # elif phases == ('l', 'L'): # cache = self._lle_cache # elif phases == ('l', 's'): # cache = self._sle_cache # else: # return None # return cache.retrieve() @property def vle(self) -> eq.VLE: """An object that can perform vapor-liquid equilibrium on the stream.""" phases = self.phases if 'l' not in phases or 'g' not in phases: self.phases = [*phases, 'l', 'g'] return self._vle_cache.retrieve() @property def lle(self) -> eq.LLE: """An object that can perform liquid-liquid equilibrium on the stream.""" phases = self.phases if 'l' not in phases or 'L' not in phases: self.phases = [*phases, 'l', 'L'] return self._lle_cache.retrieve() @property def sle(self) -> eq.SLE: """An object that can perform solid-liquid equilibrium on the stream.""" phases = self.phases if 's' not in phases or 'l' not in phases: self.phases = [*phases, 's', 'l'] return self._sle_cache.retrieve() ### Casting ###
[docs] def as_stream(self): """Convert MultiStream to Stream.""" phase = self.phase N_phase = len(phase) if N_phase == 1: self.phase = phase elif N_phase == 0: self.phase = self.phases[0] else: raise RuntimeError('multiple phases present; cannot convert to single phase stream')
[docs] def reduce_phases(self): """Remove empty phases.""" self.phase = self.phase
@property def phase(self) -> str: imol = self._imol return ''.join([phases[0] for phases in ('g', 'lL', 'sS') if not imol.phases_are_empty(phases)]) @phase.setter def phase(self, phase): N_phase = len(phase) if N_phase > 1: self.phases = phase else: if N_phase == 0: phase = 'l' # Default phase for streams self._imol = self._imol.to_chemical_indexer(phase) self._streams.clear() self.__class__ = Stream ### Representation ### def _info_str(self, units, notation, composition, N_max, all_IDs, indexer, factor): """Return string with all specifications.""" basic_info = self._basic_info() basic_info += Stream._info_phaseTP(self, self.phases, units, notation) flow_units = units['flow'] flow_notation = notation['flow'] N_all_IDs = len(all_IDs) if N_all_IDs == 0: return basic_info + ' flow: 0' # Length of chemical column all_lengths = [len(i) for i in all_IDs[:N_max]] maxlen = max(all_lengths) + 2 if composition: first_line = "composition (%):" else: first_line = f'flow ({flow_units}):' first_line_spaces = len(first_line)*" " # Set up chemical data for all phases phases_flow_rates_info = '' for phase in self.phases: phase_data = factor * indexer[phase, all_IDs] IDs, data = nonzeros(all_IDs, phase_data) data = np.array(data) if not IDs: continue if composition: total_flow = data.sum() data = 100 * data/total_flow # Get basic structure for phase data beginning = (first_line or first_line_spaces) + f' ({phase}) ' first_line = False new_line = '\n' + len(beginning) * ' ' # Set chemical data flow_rates = '' N_IDs = len(data) lengths = [len(i) for i in IDs] too_many_chemicals = N_IDs > N_max N = N_max if too_many_chemicals else N_IDs for i in range(N): spaces = ' ' * (maxlen - lengths[i]) if i: flow_rates += new_line flow_rates += f'{IDs[i]}' + spaces + f'{data[i]:{flow_notation}}' if too_many_chemicals: spaces = ' ' * (maxlen - 3) flow_rates += new_line + '...' + spaces + f'{data[N_max:].sum():{flow_notation}}' if composition: dashes = '-' * (maxlen - 2) flow_rates += f"{new_line}{dashes} {total_flow:{flow_notation}} {flow_units}" # Put it together phases_flow_rates_info += beginning + flow_rates + '\n' return basic_info + phases_flow_rates_info.rstrip('\n')
[docs] def print(self): """ Print in a format that you can use recreate the stream. Examples -------- >>> import thermosteam as tmo >>> tmo.settings.set_thermo(['Water', 'Ethanol'], cache=True) >>> s1 = tmo.MultiStream(ID='s1',T=298.15, P=101325, ... l=[('Water', 20), ('Ethanol', 10)], units='kg/hr') >>> s1.print() MultiStream(ID='s1', phases=('g', 'l'), T=298.15, P=101325, l=[('Water', 1.11), ('Ethanol', 0.2171)]) """ IDs = self.chemicals.IDs phase_data = [] for phase, data in self.imol: IDdata = utils.repr_couples(", ", IDs, data) if IDdata: phase_data.append(f"{phase}=[{IDdata}]") dlim = ", " phase_data = dlim.join(phase_data) phases = f'phases={self.phases}' if phase_data: phase_data = dlim + phase_data price = utils.repr_kwarg('price', self.price) print(f"{type(self).__name__}(ID={repr(self.ID)}, {phases}, T={self.T:.2f}, " f"P={self.P:.6g}{price}{phase_data})")