Stream#
- class Stream(ID='', flow=(), phase='l', T=298.15, P=101325.0, units=None, price=0.0, total_flow=None, thermo=None, characterization_factors=None, vlle=False, **chemical_flows)[source]#
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 (
str
, optional) – 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 (
Sequence`[:py:class:`float
]) – All flow rates corresponding to defined chemicals.phase (
str
, optional) – ‘g’ for gas, ‘l’ for liquid, and ‘s’ for solid. Defaults to ‘l’.T (
float
, optional) – Temperature [K]. Defaults to 298.15.P (
float
, optional) – Pressure [Pa]. Defaults to 101325.units (
str
, optional) – Flow rate units of measure (only mass, molar, and volumetric flow rates are valid). Defaults to ‘kmol/hr’.price (
float
, optional) – Price per unit mass [USD/kg]. Defaults to 0.total_flow (
float
, optional) – Total flow rate.thermo (
Thermo
, optional) – Thermo object to initialize input and output streams. Defaults tosettings.thermo
.characterization_factors (
dict`[:py:class:`str
,float
], optional) – Characterization factors for life cycle assessment.vlle (
bool
, optional) – 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
- display_units = DisplayUnits(T='K', P='Pa', flow='kmol/hr', composition=False, sort=False, N=7)#
Units of measure for IPython display (class attribute)
-
characterization_factors:
dict
[str
,float
]# Characterization factors for life cycle assessment [impact/kg].
- scale(scale)[source]#
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
- rescale(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
- reset_flow(phase=None, units=None, total_flow=None, **chemical_flows)[source]#
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
- get_CF(key, basis=None, units=None)[source]#
Returns the life-cycle characterization factor on a kg basis given the impact indicator key.
- Parameters:
key (
str
) – Key of impact indicator.basis (
str
, optional) – Basis of characterization factor. Mass is the only valid dimension (for now). Defaults to ‘kg’.units (
str
, optional) – Units of impact indicator. Before using this argument, the default units of the impact indicator should be defined withsettings.define_impact_indicator
. Units must also be dimensionally consistent with the default units.
- set_CF(key, value, basis=None, units=None)[source]#
Set the life-cycle characterization factor on a kg basis given the impact indicator key and the units of measure.
- Parameters:
key (
str
) – Key of impact indicator.value (
float
) – Characterization factor value.basis (
str
, optional) – Basis of characterization factor. Mass is the only valid dimension (for now). Defaults to ‘kg’.units (
str
, optional) – Units of impact indicator. Before using this argument, the default units of the impact indicator should be defined withsettings.define_impact_indicator
. Units must also be dimensionally consistent with the default units.
- empty_negative_flows()[source]#
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
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
- get_data()[source]#
Return a StreamData object containing data on material flow rates, temperature, pressure, and phase(s).
See also
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
- set_data(stream_data)[source]#
Set material flow rates, temperature, pressure, and phase(s) through a StreamData object
See also
- isempty()[source]#
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
- sanity_check()[source]#
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
- get_atomic_flow(symbol)[source]#
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
- get_atomic_flows()[source]#
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}
- get_flow(units, key=Ellipsis)[source]#
Return an flow rates in requested units.
- Parameters:
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
- set_flow(data, units, key=Ellipsis)[source]#
Set flow rates in given units.
- Parameters:
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
- get_total_flow(units)[source]#
Get total flow rate in given units.
- Parameters:
units (
str
) – 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
- set_total_flow(value, units)[source]#
Set total flow rate in given units keeping the composition constant.
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
- property thermal_condition: ThermalCondition#
Contains the temperature and pressure conditions of the stream.
- property mass: SparseVector | SparseArray#
Mass flow rates [kg/hr].
- property vol: SparseVector | SparseArray#
Volumetric flow rates [m3/hr].
- in_thermal_equilibrium(other)[source]#
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
- classmethod sum(streams, ID=None, thermo=None, energy_balance=True, vle=False)[source]#
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
- separate_out(other, energy_balance=True)[source]#
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
- mix_from(others, energy_balance=True, vle=False, Q=0.0, conserve_phases=False)[source]#
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
- split_to(s1, s2, split, energy_balance=True)[source]#
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
- link_with(other, flow=True, phase=True, TP=True)[source]#
Link with another stream.
- Parameters:
See also
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'
- unlink()[source]#
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
- copy_like(other)[source]#
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
- copy_thermal_condition(other)[source]#
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
- copy_flow(other, IDs=Ellipsis, *, remove=False, exclude=False)[source]#
Copy flow rates of another stream to self.
- Parameters:
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
- copy(ID=None, thermo=None)[source]#
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
Warning
Prices, and LCA characterization factors are not copied.
- flow_proxy(ID=None)[source]#
Return a new stream that shares flow rate data with this one.
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
- proxy(ID=None)[source]#
Return a new stream that shares all data with this one.
See also
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
- empty()[source]#
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
- vlle(T, P)[source]#
Estimate vapor-liquid-liquid equilibrium.
Warning
This method may be as slow as 1 second.
- get_bubble_point(IDs=None)[source]#
Return a BubblePoint object capable of computing bubble points.
- Parameters:
IDs (
Sequence`[:py:class:`str
], optional) – 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])
- get_dew_point(IDs=None)[source]#
Return a DewPoint object capable of computing dew points.
- Parameters:
IDs (
Sequence`[:py:class:`str
], optional) – 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])
- bubble_point_at_T(T=None, IDs=None)[source]#
Return a BubblePointResults object with all data on the bubble point at constant temperature.
- Parameters:
T (
float
, optional) – Temperature [K].IDs (
Sequence`[:py:class:`str
], optional) – 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])
- bubble_point_at_P(P=None, IDs=None)[source]#
Return a BubblePointResults object with all data on the bubble point at constant pressure.
- Parameters:
IDs (
Sequence`[:py:class:`str
], optional) – 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])
- dew_point_at_T(T=None, IDs=None)[source]#
Return a DewPointResults object with all data on the dew point at constant temperature.
- Parameters:
IDs (
Sequence`[:py:class:`str
], optional) – 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])
- dew_point_at_P(P=None, IDs=None)[source]#
Return a DewPointResults object with all data on the dew point at constant pressure.
- Parameters:
IDs (
Sequence`[:py:class:`str
], optional) – 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])
- get_normalized_mol(IDs)[source]#
Return normalized molar fractions of given chemicals. The sum of the result is always 1.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_normalized_mass(IDs)[source]#
Return normalized mass fractions of given chemicals. The sum of the result is always 1.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_normalized_vol(IDs)[source]#
Return normalized mass fractions of given chemicals. The sum of the result is always 1.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_molar_fraction(IDs)[source]#
Return molar fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_molar_composition(IDs)#
Return molar fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_mass_fraction(IDs)[source]#
Return mass fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_mass_composition(IDs)#
Return mass fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_volumetric_fraction(IDs)[source]#
Return volumetric fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_volumetric_composition(IDs)#
Return volumetric fraction of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – 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])
- get_concentration(IDs, units=None)[source]#
Return concentration of given chemicals.
- Parameters:
IDs (
Sequence`[:py:class:`str
]) – IDs of chemicals.units (
str
, optional) – 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])
- receive_vent(other, energy_balance=True, ideal=False)[source]#
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
- property ID#
Unique identification (str). If set as ‘’, it will choose a default ID.
- get_property(name, units=None)#
Return property in requested units.
- set_property(name, value, units=None)#
Set property in given units.
- show(layout=None, T=None, P=None, flow=None, composition=None, N=None, IDs=None, sort=None, df=None)[source]#
Print all specifications.
- Parameters:
layout (
str
, optional) – 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 (
str
, optional) – Temperature units.P (
str
, optional) – Pressure units.flow (
str
, optional) – Flow rate units.composition (
bool
, optional) – Whether to show composition.N (
int
, optional) – Number of compounds to display.IDs (
Sequence`[:py:class:`str
], optional) – IDs of compounds to display. Defaults to all chemicals.sort (
bool
, optional) – Whether to sort flows in descending order.df (
bool
, optional) – 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(units=None)[source]#
Print in a format that you can use recreate the stream.
- Parameters:
units (
str
, optional) – 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')