surfaceroughness

[ustar, z0, d] = surfaceroughness(z, u, delta, dispout)

Description

Calculate shear velocity and surface roughness from a given velocity profile using Karimpour et al. (2012) method

Inputs

z

Distance from a surface (elevation, height) in (m)

u

Velocity at z in (m/s)

delta=max(z);

Boundary layer height in (m)

dispout=’no’;

Define to display outputs or not (‘yes’: display, ‘no’: not display)

Outputs

z0

Surface roughness in (m)

ustar

Shear velocity (u*) in (m/s)

d

Zero plane displacement distance in (m)

Note: Above values are for a logarithmic velocity profile as:

u=(u*/K)*ln((z-d)/z0)

Examples

z(:,1)=[0.1:0.05:1];
u(:,1)=2/0.4*log((z-0.003)/0.002);
[ustar,z0,d]=surfaceroughness(z,u,max(z),'yes');

References

Karimpour, A., Kaye, N. B., & Baratian-Ghorghi, Z. (2012). Modeling the neutrally stable atmospheric boundary layer for laboratory scale studies of the built environment. Building and Environment, 49, 203-211.