Engelund-Hansen formula

Transport capacity is calculated as follows :

$$C_{eq}=0.05\rho_S\frac{LU^2}{Q}\frac{(JR)^{\frac{3}{2}}}{\sqrt{g} (\rho_S/\rho-1)^2d}$$

where :

• $ \rho_S$ is the sediment’s density (kg/m³)
• $ L $ is the stream’s width (m)
• $ U $ is the mean velocity (m/s)
• $ Q $ is the water discharge (m³/s)
• $ J $ is the slope (m/m)
• $ R $ is the hydraulic radius (m)
• $ g $ is the gravity (m/s²)
• $ \rho $ is the density of water (kg/m³)
• $ d $ is the sediment diameter

Specifications

• Law’s ID : 561
• Number of acting classes : 4
• Number of parameters : 6

Acting classes :

1. $ C_i $ : transported class modified by the law
2. $ C_j $ : fix class modified by the law
3. $ C_k $ : transported parameter class ($i=k$ for standard use)
4. $ T $ : water temperature

Parameters :

1. $ d $ : sediment diameter
2. $ \rho_S$ : sediment density
3. $ p $ : sediment porosity
4. $ \alpha$
5. $ i_{ech}$ : exchange formula : 1 = Han, 2 = Hazen
6. $\beta$