v2026.11.16174
Reference / Input deck / model / fluid zones / canopy

canopy

type: canopy

Canopy model fluid zone for atmospheric boundary layer simulations with vegetation.

cell zones
list of int·not set by default·give only one of 'cell zones', 'definition' or 'field'

Mesh cell zone numbers whose cells form the canopy, for example "cell zones": [4]; give this, 'definition' or 'field', or neither for the whole mesh

Guidance: Choosing a fluid-zone model →
definition
str·not set by default

Closed-surface VTP file selecting the canopy cells; without it, 'cell zones' or 'field' the canopy covers the whole mesh

Used incanopy
Guidance: Choosing a fluid-zone model →
field
str·not set by default

Field file for canopy definition (alternative to VTP)

Guidance: Choosing a fluid-zone model →
function
Python function·not set by default·accepts a Python function

Function of the cell centres and their wall distances giving the leaf area density (1/m) in every canopy cell, called as f(*, locations, wall_distances); it returns a list of one leaf area density per location

Used incanopy
Guidance: Python functions in the deck →
cd
float·default 0.25·>= 0

Drag coefficient for canopy momentum sink

Used incanopy
beta p
float·default 0.17·>= 0

Canopy turbulence production parameter

Used incanopy
beta d
float·default 3.37·>= 0

Canopy turbulence dissipation parameter

Used incanopy
ceps 4
float·default 0.9·>= 0

Canopy C_epsilon_4 turbulence parameter

Used incanopy
ceps 5
float·default 0.9·>= 0

Canopy C_epsilon_5 turbulence parameter

Used incanopy