modelFrictionSpec
Reusable friction specification with multiple input methods
Information
Friction Specification
Partial model providing a reusable friction parameter set. Extending models must supply
the hydraulic diameter D_h used for converting Moody and Manning coefficients
to equivalent pipe roughness height p_eps.
Three friction specification methods are supported via the FrictionMethod parameter:
- Pipe Roughness (p_eps): Direct specification of absolute pipe roughness height (m). Typical values: 0.0001–0.001 m for steel pipes, 0.001–0.003 m for concrete.
- Moody Friction Factor (f): Dimensionless friction factor from Moody diagram. Typical values: 0.01–0.05. Converted to equivalent roughness using fully turbulent flow approximation: p_eps = 3.7·D·10-1/(2√f)
- Manning Coefficient: Two notations are supported:
- Manning's M coefficient (Strickler) [m1/3/s]: M = 1/n, typical values 60–110 for steel, 30–60 for rock tunnels.
- Manning's n coefficient [s/m1/3]: Typical values 0.009–0.013 for smooth steel,
0.012–0.017 for concrete, 0.017–0.030 for rock tunnels. Use checkbox
use_nto enable.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Friction | |||
| Types.FrictionMethod | FrictionMethod | data.FrictionMethod | Method for specifying pipe friction |
| SI.Height | p_eps_input | data.p_eps | Pipe roughness height (absolute) |
| Real | f_moody | data.f_moody | Moody friction factor (dimensionless, typically 0.01-0.05) |
| Real | m_manning | data.m_manning | Manning M (Strickler) coefficient M=1/n (typically 60-110 for steel, 30-60 for rock tunnels) |
| Boolean | use_n | data.use_n | If true, use Mannings coefficient n (=1/M) instead of Manning's M (Strickler) |
| Real | n_manning | data.n_manning | Manning's n coefficient (typically 0.009-0.017 for steel/concrete, 0.017-0.030 for rock tunnels) |
| SI.Diameter | D_h | Hydraulic diameter used for friction conversion | |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Data | data | Using standard data set |