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API Reference

This page contains the automatically generated API reference for the relperm package.

The docstrings are extracted directly from the source code and rendered with full equation support.

Core Functions

s_eff 

s_eff(sw, swr, snwr)

Calculate the effective wetting phase saturation.

Parameters:

Name Type Description Default
sw NDArray[float64]

Wetting phase saturation array.

 required
swr float64

Residual wetting phase saturation.

 required
snwr float64

Residual non-wetting phase saturation.

 required

Returns:

Type Description
NDArray[float64]

Effective wetting phase saturation array.
Notes

The effective saturation (\(S_{eff}\)) is calculated using the formula:

\[S_{eff} = \frac{S_w - S_{wr}}{1 - S_{wr} - S_{nwr}}\]

where:

  • \(S_w\): Wetting phase saturation.
  • \(S_{wr}\): Residual wetting phase saturation.
  • \(S_{nwr}\): Residual non-wetting phase saturation.
Source code in src/relperm/relperm.py 
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def s_eff(
    sw: npt.NDArray[np.float64], swr: np.float64, snwr: np.float64
) -> npt.NDArray[np.float64]:
    r"""Calculate the effective wetting phase saturation.

    Parameters
    ----------
    sw : npt.NDArray[np.float64]
        Wetting phase saturation array.
    swr : np.float64
        Residual wetting phase saturation.
    snwr : np.float64
        Residual non-wetting phase saturation.

    Returns
    -------
    npt.NDArray[np.float64]
        Effective wetting phase saturation array.

    Notes
    -----
    The effective saturation ($S_{eff}$) is calculated using the formula:

    $$S_{eff} = \frac{S_w - S_{wr}}{1 - S_{wr} - S_{nwr}}$$

    where:

    - $S_w$: Wetting phase saturation.
    - $S_{wr}$: Residual wetting phase saturation.
    - $S_{nwr}$: Residual non-wetting phase saturation.
    """
    s_eff_array = (sw - swr) / (1 - swr - snwr)

    return s_eff_array

krw 

krw(s_eff, krw0, nw)

Calculate the relative permeability of the wetting phase.

Parameters:

Name Type Description Default
s_eff NDArray[float64]

Effective wetting phase saturation array.

 required
krw0 float64

Endpoint relative permeability for the wetting phase.

 required
nw float64

Corey exponent for the wetting phase.

 required

Returns:

Type Description
NDArray[float64]

Relative permeability of the wetting phase array.
Notes

The relative permeability of the wetting phase (\(k_{rw}\)) is calculated using the Corey model:

\[k_{rw} = k_{rw0} \cdot S_{eff}^{n_w}\]

where:

  • \(k_{rw0}\) is the endpoint relative permeability for the wetting phase.
  • \(S_{eff}\) is the effective wetting phase saturation.
  • \(n_w\) is the Corey exponent for the wetting phase.
Source code in src/relperm/relperm.py 
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def krw(
    s_eff: npt.NDArray[np.float64], krw0: np.float64, nw: np.float64
) -> npt.NDArray[np.float64]:
    r"""Calculate the relative permeability of the wetting phase.

    Parameters
    ----------
    s_eff : npt.NDArray[np.float64]
        Effective wetting phase saturation array.
    krw0 : np.float64
        Endpoint relative permeability for the wetting phase.
    nw : np.float64
        Corey exponent for the wetting phase.

    Returns
    -------
    npt.NDArray[np.float64]
        Relative permeability of the wetting phase array.

    Notes
    -----
    The relative permeability of the wetting phase ($k_{rw}$) is calculated using the
    Corey model:

    $$k_{rw} = k_{rw0} \cdot S_{eff}^{n_w}$$

    where:

    - $k_{rw0}$ is the endpoint relative permeability for the wetting phase.
    - $S_{eff}$ is the effective wetting phase saturation.
    - $n_w$ is the Corey exponent for the wetting phase.
    """
    krw_array = krw0 * s_eff**nw

    return krw_array