n_strickler1923 {HYDROCAL}

Compute grain roughness following Strickler (1923)

Description

n_strickler1923 calculate Manning's n using the Strickler (1923) method for estimating grain roughness

Usage

n_strickler1923(grain, restrict = TRUE)

Arguments

grain

grain size (d50) in millimeters

restrict

allows for function parameters to restrict certain values. Type bool. Default TRUE.

Value

Manning's n

References

Strickler, A. 1923. Contributions to the Question of a Velocity formula and Roughness Data for Streams, Channels Closed Pipelines, translated by T. Roesgan and W.R. Brownlie. Translation T-10, W.M. Keck Lab of Hydraulics and Water Resources, California Institute of Technology, Pasadena, CA.

Examples

# Result: Manning's n of 0.032
n_strickler1923(100)

# Result: Manning's n of 0.025
n_strickler1923(20)

# Result: Manning's n of 0.021
n_strickler1923(8)

# Result: Grain size (mm) must be positive
n_strickler1923(-8)