Here, ‘−’ and ‘
+’ refer to the upstream and downstream side of the screen, respectively. Furthermore,
K is the dimensionless resistance coefficient, which parameterizes the magnitude of the drag exerted by the screen on the flow.
η is the dimensionless refraction coefficient, which parameterizes the extent to which the screen causes the flow to change direction to align parallel to the normal downstream direction from the plane of the screen. The refraction coefficient should be between
0 and
1. Isotropic turbulence is expected on the downstream side of the screen, hence,
The attenuation of the turbulence kinetic energy (Equation 3-48) is based on the suppression of the tangential velocity (
Equation 3-47) and the changes in
ε and
ω are determined by the assumption of preservation of the turbulence length-scale across the screen.
Here σs is the solidity (ratio of blocked area to total area of the screen) and
d is the diameter of the wires. For a square mesh, the correlation