Skip to content

polykin.properties.viscosity¤

MUVMX_Lucas ¤

MUVMX_Lucas(
    T: float,
    P: float,
    y: FloatVectorLike,
    M: FloatVectorLike,
    Tc: FloatVectorLike,
    Pc: FloatVectorLike,
    Zc: FloatVectorLike,
    dm: FloatVectorLike,
) -> float

Calculate the viscosity of a gas mixture at a given temperature and pressure using the method of Lucas.

References

  • RC Reid, JM Prausniz, and BE Poling. The properties of gases & liquids 4th edition, 1986, p. 431.
PARAMETER DESCRIPTION
T

Temperature [K].

TYPE: float

P

Pressure [Pa].

TYPE: float

y

Mole fractions of all components [mol/mol].

TYPE: FloatVectorLike(N)

M

Molar masses of all components [kg/mol].

TYPE: FloatVectorLike(N)

Tc

Critical temperatures of all components [K].

TYPE: FloatVectorLike(N)

Pc

Critical pressures of all components [Pa].

TYPE: FloatVectorLike(N)

Zc

Critical compressibility factors of all components.

TYPE: FloatVectorLike(N)

dm

Dipole moments of all components [debye].

TYPE: FloatVectorLike(N)

RETURNS DESCRIPTION
float

Gas mixture viscosity, \(\mu_m\) [Pa·s].

Examples:

Estimate the viscosity of a 60 mol% ethylene/nitrogen gas mixture at 350 K and 10 bar.

>>> from polykin.properties.viscosity import MUVMX_Lucas
>>> y = [0.6, 0.4]
>>> M = [28.e-3, 28.e-3]   # kg/mol
>>> Tc = [282.4, 126.2]    # K
>>> Pc = [50.4e5, 33.9e5]  # Pa
>>> Zc = [0.280, 0.290]
>>> dm = [0., 0.]
>>> mu_mix = MUVMX_Lucas(T=350., P=10e5, y=y, M=M,
...                      Tc=Tc, Pc=Pc, Zc=Zc, dm=dm)
>>> print(f"{mu_mix:.2e} Pa·s")
1.45e-05 Pa·s
Source code in src/polykin/properties/viscosity/vapor.py
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
def MUVMX_Lucas(T: float,
                P: float,
                y: FloatVectorLike,
                M: FloatVectorLike,
                Tc: FloatVectorLike,
                Pc: FloatVectorLike,
                Zc: FloatVectorLike,
                dm: FloatVectorLike
                ) -> float:
    r"""Calculate the viscosity of a gas mixture at a given temperature and
    pressure using the method of Lucas.

    **References**

    *   RC Reid, JM Prausniz, and BE Poling. The properties of gases & liquids
        4th edition, 1986, p. 431.

    Parameters
    ----------
    T : float
        Temperature [K].
    P : float
        Pressure [Pa].
    y : FloatVectorLike (N)
        Mole fractions of all components [mol/mol].
    M : FloatVectorLike (N)
        Molar masses of all components [kg/mol].
    Tc : FloatVectorLike (N)
        Critical temperatures of all components [K].
    Pc : FloatVectorLike (N)
        Critical pressures of all components [Pa].
    Zc : FloatVectorLike (N)
        Critical compressibility factors of all components.
    dm : FloatVectorLike (N)
        Dipole moments of all components [debye].

    Returns
    -------
    float
        Gas mixture viscosity, $\mu_m$ [Pa·s].

    Examples
    --------
    Estimate the viscosity of a 60 mol% ethylene/nitrogen gas mixture at 350 K
    and 10 bar.

    >>> from polykin.properties.viscosity import MUVMX_Lucas
    >>> y = [0.6, 0.4]
    >>> M = [28.e-3, 28.e-3]   # kg/mol
    >>> Tc = [282.4, 126.2]    # K
    >>> Pc = [50.4e5, 33.9e5]  # Pa
    >>> Zc = [0.280, 0.290]
    >>> dm = [0., 0.]
    >>> mu_mix = MUVMX_Lucas(T=350., P=10e5, y=y, M=M,
    ...                      Tc=Tc, Pc=Pc, Zc=Zc, dm=dm)
    >>> print(f"{mu_mix:.2e} Pa·s")
    1.45e-05 Pa·s
    """
    y = np.asarray(y)
    M = np.asarray(M)
    Tc = np.asarray(Tc)
    Pc = np.asarray(Pc)
    Zc = np.asarray(Zc)
    dm = np.asarray(dm)

    Tc_mix = dot(y, Tc)
    M_mix = dot(y, M)
    Pc_mix = R*Tc_mix*dot(y, Zc)/dot(y, R*Tc*Zc/Pc)
    FP0_mix = dot(y, _MUV_Lucas_FP0(T/Tc, Tc, Pc, Zc, dm))
    mu = _MUV_Lucas_mu(
        T/Tc_mix, P/Pc_mix, M_mix, Tc_mix, Pc_mix, FP0_mix)

    return mu