environmentaltools.processes.river_sediment_transport

environmentaltools.processes.river_sediment_transport(df, info, type_='meyer-peter-muller')

Calculate river bed-load sediment transport rate using various formulas.

Computes sediment transport in rivers using established empirical and semi-empirical formulas. Supports multiple methods for different grain sizes and flow conditions.

Parameters:

• df (pd.DataFrame) – DataFrame with hydraulic variables: - h : Water depth (m)

• info (dict) –

  Dictionary with sediment and channel properties:

  • rho_wfloat

    Water density (kg/m³)

  • rho_sfloat

    Sediment density (kg/m³)

  • sgfloat

    Specific gravity of sediment (dimensionless)

  • d50float

    Median grain diameter (m)

  • Sfloat

    Channel bed slope (m/m)

  • wfloat

    Channel width (m)

  • nufloat

    Kinematic viscosity (m²/s, for some methods)

  • ds_substratearray-like

    Grain size distribution (for Wilcock-Crowe, Yang, Brownlie)

  • frac_substratearray-like

    Fraction of each grain size class (for Wilcock-Crowe)

  • nfloat

    Manning’s roughness coefficient (for some methods)

• type (str, optional) – Sediment transport formula. Options: - ‘meyer-peter-muller’ : Meyer-Peter & Müller (1948) for gravel rivers - ‘einstein-brown’ : Einstein & Brown (1942) probabilistic approach - ‘wilcock-crowe’ : Wilcock & Crowe (2003) for mixed-size sediments - ‘bagnold’ : Bagnold (1966) stream power approach - ‘yang’ : Yang (1973) for sand-bed rivers - ‘brownlie’ : Brownlie (1981) comprehensive formula Default: ‘meyer-peter-muller’

Returns:

Bed-load sediment transport rate Qb (m³/hour or m³/s depending on formula)

Return type:

pd.Series or np.ndarray

Notes

Meyer-Peter-Müller formula:

qb* = 8 * (τ* - τ*c)^1.5

Valid for gravel-bed rivers with uniform sediment

Einstein-Brown formula:

Uses probability approach with three transport regimes based on τ*

Wilcock-Crowe formula:

Accounts for hiding/exposure effects in mixed-size sediments

Requires grain size distribution input

Bagnold formula:

Based on stream power concept: qb ∝ τ * U

Yang formula:

Empirical formula for sand transport in terms of unit stream power

Brownlie formula:

General formula with dimensionless critical Shields parameter

References

• Meyer-Peter, E., & Müller, R. (1948)

• Einstein, H. A., & Brown, C. B. (1942)

• Wilcock, P. R., & Crowe, J. C. (2003)

• Bagnold, R. A. (1966)

• Yang, C. T. (1973)

• Brownlie, W. R. (1981)