# Chezy Coefficient

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

Chezy coefficient, abbreviated as C, a dimensionless number, dependent on surface roughness and the hydraulic mean depth.

## Chezy coefficient formulas

 $$\large{ C = \frac{1}{n} \; r_h^{1/6} }$$ $$\large{ C = \frac{v_m}{ \sqrt{ \; r_h \; m } } }$$

### Where:

 Units English Metric $$\large{ C }$$ = Chezy coefficient $$\large{ dimensionless }$$ $$\large{ r_h }$$ = hydraulic radius $$\large{ ft }$$ $$\large{ m }$$ $$\large{ v_m }$$ = mean velocity $$\large{ \frac{ft}{sec} }$$ $$\large{ \frac{m}{s} }$$ $$\large{ n }$$ = roughness coefficient $$\large{ dimensionless }$$ $$\large{ m }$$ = slope $$\large{ ft }$$ $$\large{ m }$$