Source code for uwg.infracalcs
"""Functions for calculating canyon infrared radiation."""
SIGMA = 5.67e-8 # Stephen-Boltzman const
[docs]def infracalcs(UCM, forc, e_road, e_wall, T_road, T_wall):
"""Calculate infrared radiation surface flux on canyon wall and road.
Args:
UCM: UCMDef object.
forc: Forcing object.
e_road: Number for road emissivity.
e_wall: Number for wall emissivity.
T_road: Number for road surface temperature (K).
T_wall: Number for wall surface temperature (K).
Returns:
Tuple of two values
- infra_road: Road infrared radiation (W)
- infra_wall: Wall infrared radiation (W)
"""
# road_wall_conf: configuration factor (view factor) for road to wall
road_wall_conf = (1. - UCM.roadConf)
# wall_road_conf: wall to road VF same as wall-sky configuration factors
# (sky view factor)
wall_road_conf = UCM.wallConf
# Calculate radiation of unshaded road, accounting for radiation exchange from wall
_road_rad = \
e_road * UCM.roadConf * (1. - UCM.roadShad) * (forc.infra - SIGMA * T_road ** 4.)
_wall_to_road_rad = \
(1. - UCM.roadShad) * e_wall * e_road * SIGMA * road_wall_conf * (T_wall ** 4. - T_road ** 4.)
infra_road = _road_rad + _wall_to_road_rad
# Calculate radiation of wall, accounting for radiation exchange from unshaded road
_road_rad = e_wall * UCM.wallConf * (forc.infra - SIGMA * T_wall ** 4.)
_road_to_wall_rad = \
(1. - UCM.roadShad) * e_wall * e_road * SIGMA * wall_road_conf * (T_road ** 4. - T_wall ** 4.)
infra_wall = _road_rad + _road_to_wall_rad
return infra_road, infra_wall