Stream

class thermosteam.Stream(ID='', flow=(), phase='l', T=298.15, P=101325.0, units='kmol/hr', price=0.0, thermo=None, **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) – 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=() (Iterable[float]) – All flow rates corresponding to chemical IDs.
phase='l' ('l', 'g', or 's') – Either gas (g), liquid (l), or solid (s).
T=298.15 (float) – Temperature [K].
P=101325 (float) – Pressure [Pa].
units='kmol/hr' (str) – Flow rate units of measure (only mass, molar, and volumetric flow rates are valid).
price=0 (float) – Price per unit mass [USD/kg].
thermo=None (Thermo) – Thermo object to initialize input and output streams. Defaults to biosteam.settings.get_thermo().
**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    0.667
              Ethanol  0.333
              -------  30 kg/hr

All flow rates are stored as an array in the mol attribute:

>>> s1.mol # Molar flow rates [kmol/hr]
array([1.11 , 0.217])

Mass and volumetric flow rates are available as property arrays:

>>> s1.mass
property_array([<Water: 20 kg/hr>, <Ethanol: 10 kg/hr>])
>>> s1.vol
property_array([<Water: 0.02006 m^3/hr>, <Ethanol: 0.012722 m^3/hr>])

These arrays work just like ordinary arrays, but the data is linked to the molar flows:

>>> # Mass flows are always up to date with molar flows
>>> s1.mol[0] = 1
>>> s1.mass[0]
<Water: 18.015 kg/hr>
>>> # Changing mass flows changes molar flows
>>> s1.mass[0] *= 2
>>> s1.mol[0]
2.0
>>> # Property arrays act just like normal arrays
>>> s1.mass + 2
array([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
1083.467954...

Other thermodynamic properties are temperature and pressure dependent as well:

>>> s1.rho # Density [kg/m3]
908.8914226...

It may be more convinient to get properties with different units:

>>> s1.get_property('rho', 'g/cm3')
0.90889142...

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=357.09, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.49 0.51])

The bubble point results contain all results as attributes:

>>> bp.T # Temperature [K]
357.088...
>>> 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: 364.8 K, P: 101325 Pa
 flow (kmol/hr): (g) Water    0.472
                     Ethanol  0.192
                 (l) Water    0.638
                     Ethanol  0.0255

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: 364.8 K, P: 101325 Pa
 flow (kmol/hr): Water    0.638
                 Ethanol  0.0255

>>> s1['g'].show()
Stream:
 phase: 'g', T: 364.8 K, P: 101325 Pa
 flow (kmol/hr): Water    0.472
                 Ethanol  0.192

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: 364.8 K, P: 101325 Pa
 flow (kg/hr): Water    20
               Ethanol  10

display_units = DisplayUnits(T='K', P='Pa', flow='kmol/hr', composition=False, N=7): [DisplayUnits] Units of measure for IPython display (class attribute)

as_stream()[source]: Does nothing.

property price: [float] Price of stream per unit mass [USD/kg.

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

property vapor_fraction: Molar vapor fraction.

property liquid_fraction: Molar liquid fraction.

property solid_fraction: Molar solid fraction.

isfeed()[source]: Return whether stream has a sink but no source.

isproduct()[source]: Return whether stream has a source but no sink.

property main_chemical: [str] ID of chemical with the largest mol fraction in stream.

disconnect()[source]: Disconnect stream from unit operations.

get_atomic_flow(symbol)[source]

Return flow rate of atom in 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 in 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

units (str) – Units of measure.
key (tuple[str] or str, optional) – 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

set_flow(data, units, key=Ellipsis)[source]

Set flow rates in given units.

Parameters

data (1d ndarray or float) – Flow rate data.
units (str) – Units of measure.
key (Iterable[str] or str, optional) – 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

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.

Parameters

value (float) – New total flow rate.
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.set_total_flow(1.0,'kg/hr')
>>> s1.get_total_flow('kg/hr')
0.9999999999999999

get_property(name, units)[source]

Return property in requested units.

Parameters

name (str) – Name of stream property.
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_property('sigma', 'N/m') # Surface tension
0.063780393

set_property(name, value, units)[source]

Set property in given units.

Parameters

name (str) – Name of stream property.
value (str) – New value of stream property.
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.set_property('P', 2, 'atm')
>>> s1.P
202650.0

property source: [Unit] Outlet location.

property sink: [Unit] Inlet location.

property thermal_condition: [ThermalCondition] Contains the temperature and pressure conditions of the stream.

property T: [float] Temperature in Kelvin.

property P: [float] Pressure in Pascal.

property phase: Phase of stream.

property mol: [array] Molar flow rates in kmol/hr.

property mass: [property_array] Mass flow rates in kg/hr.

property vol: [property_array] Volumetric flow rates in m3/hr.

property imol: [Indexer] Flow rate indexer with data in kmol/hr.

property imass: [Indexer] Flow rate indexer with data in kg/hr.

property ivol: [Indexer] Flow rate indexer with data in m3/hr.

property cost: [float] Total cost of stream in USD/hr.

property F_mol: [float] Total molar flow rate in kmol/hr.

property F_mass: [float] Total mass flow rate in kg/hr.

property F_vol: [float] Total volumetric flow rate in m3/hr.

property H: [float] Enthalpy flow rate in kJ/hr.

property S: [float] Absolute entropy flow rate in kJ/hr.

property Hnet: [float] Total enthalpy flow rate (including heats of formation) in kJ/hr.

property Hf: [float] Enthalpy of formation flow rate in kJ/hr.

property LHV: [float] Lower heating value flow rate in kJ/hr.

property HHV: [float] Higher heating value flow rate in kJ/hr.

property Hvap: [float] Enthalpy of vaporization flow rate in kJ/hr.

property C: [float] Heat capacity flow rate in kJ/K/hr.

property z_mol: [1d array] Molar composition.

property z_mass: [1d array] Mass composition.

property z_vol: [1d array] Volumetric composition.

property MW: [float] Overall molecular weight.

property V: [float] Molar volume [m^3/mol].

property kappa: [float] Thermal conductivity [W/m/k].

property Cn: [float] Molar heat capacity [J/mol/K].

property mu: [float] Hydrolic viscosity [Pa*s].

property sigma: [float] Surface tension [N/m].

property epsilon: [float] Relative permittivity [-].

property Cp: [float] Heat capacity [J/g/K].

property alpha: [float] Thermal diffusivity [m^2/s].

property rho: [float] Density [kg/m^3].

property nu: [float] Kinematic viscosity [-].

property Pr: [float] Prandtl number [-].

property available_chemicals: list[Chemical] All chemicals with nonzero flow.

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)[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

mix_from(others)[source]

Mix all other streams into this one, ignoring its initial contents.

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

split_to(s1, s2, split)[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

other (Stream) –
flow (bool, defaults to True) – Whether to link the flow rate data.
phase (bool, defaults to True) – Whether to link the phase.
TP (bool, defaults to True) – Whether to link the temperature and pressure.

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

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(stream, IDs=Ellipsis, *, remove=False, exclude=False)[source]

Copy flow rates of stream to self.

Parameters

stream (Stream) – Flow rates will be copied from here.
IDs=... (Iterable[str], defaults to all chemicals.) – Chemical IDs.
remove=False (bool, optional) – If True, copied chemicals will be removed from stream.
exclude=False (bool, optional) – 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(ID=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 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.

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
0.0

property vle: [VLE] An object that can perform vapor-liquid equilibrium on the stream.

property lle: [LLE] An object that can perform liquid-liquid equilibrium on the stream.

property sle: [SLE] An object that can perform solid-liquid equilibrium on the stream.

property vle_chemicals: list[Chemical] Chemicals cabable of liquid-liquid equilibrium.

property lle_chemicals: list[Chemical] Chemicals cabable of vapor-liquid equilibrium.

get_bubble_point(IDs=None)[source]

Return a BubblePoint object capable of computing bubble points.

Parameters: IDs (Iterable[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 (Iterable[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: IDs (Iterable[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=76622, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.486 0.514])

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 (Iterable[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=357.09, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], y=[0.49 0.51])

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 (Iterable[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=48991, 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 (Iterable[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=368.66, P=101325, IDs=('Water', 'Ethanol'), z=[0.836 0.164], x=[0.984 0.016])

get_normalized_mol(IDs)[source]

Return normalized molar fractions of given chemicals. The sum of the result is always 1.

Parameters: IDs (tuple[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 (tuple[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 (tuple[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_composition(IDs)[source]

Return molar composition of given chemicals.

Parameters: IDs (tuple[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_composition(('Water', 'Ethanol'))
array([0.5 , 0.25])

get_mass_composition(IDs)[source]

Return mass composition of given chemicals.

Parameters: IDs (tuple[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_composition(('Water', 'Ethanol'))
array([0.5 , 0.25])

get_volumetric_composition(IDs)[source]

Return volumetric composition of given chemicals.

Parameters: IDs (tuple[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_composition(('Water', 'Ethanol'))
array([0.5 , 0.25])

property ID: Unique identification (str). If set as ‘’, it will choose a default ID.

get_concentration(IDs)[source]

Return concentration of given chemicals in kmol/m3.

Parameters: IDs (tuple[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_concentration(('Water', 'Ethanol'))
array([27.671,  4.266])

property P_vapor: Vapor pressure of liquid.

receive_vent(other, accumulate=False, fraction=1.0)[source]

Receive vapors from another stream as if in equilibrium.

Notes

Disregards energy balance. Assumes liquid composition will not change significantly.

Examples

>>> 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=10, units='m3/hr', phase='g', T=330)
>>> s2 = tmo.Stream('s2', Water=10, Ethanol=2, T=330)
>>> s1.receive_vent(s2, accumulate=True)
>>> s1.show(flow='kmol/hr')
Stream: s1
 phase: 'g', T: 330 K, P: 101325 Pa
 flow (kmol/hr): Water    0.0557
                 Ethanol  0.0616
                 N2       0.369

property link: [Stream] Data on the thermal condition and material flow rates may be shared with this stream.

property phases: tuple[str] All phases present.

show(T=None, P=None, flow=None, composition=None, N=None)[source]

Print all specifications.

Parameters

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.

Notes

Default values are stored in Stream.display_units.

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')