Cold Air Flow

Author: O.Conrad, H.Dietrich (c) 2020
Menu: Simulation | Air Flow

Description

A simple cold air flow simulation.

References

Bendix, J. (2005): Gelaendeklimatologie. Studienreihe Geographie.
Schwab, A. (2000): Reliefanalytische Verfahren zur Abschaetzung naechtlicher Kaltluftbewegungen. Freiburger Geographische Hefte, 61.

Parameters

	Name	Type	Identifier	Description	Constraints
Input	Elevation	grid, input	`DEM`	-	-
	Production	grid, input, optional	`PRODUCTION`	Rate of cold air production [m/h].	-
	Surface Friction Coefficient	grid, input, optional	`FRICTION`	Surface friction coefficient.	-
Output	Cold Air Height	grid, output	`AIR`	-	-
Output	Velocity	grid, output, optional	`VELOCITY`	-	-
Options	Grid System	grid system	`PARAMETERS_GRID_SYSTEM`	-	-
	Default	floating point number	`PRODUCTION_DEFAULT`	default value if no grid has been selected	Minimum: 0.000000 Default: 1.000000
	Default	floating point number	`FRICTION_DEFAULT`	default value if no grid has been selected	Minimum: 0.000000 Default: 1.000000
	Reset	boolean	`RESET`	-	Default: 1
	Simulation Time [h]	floating point number	`TIME_STOP`	Simulation time in hours.	Minimum: 0.000000 Default: 6.000000
	Map Update Frequency [min]	floating point number	`TIME_UPDATE`	-	Minimum: 0.000000 Default: 10.000000
	Edge	choice	`EDGE`	-	Available Choices: [0] closed [1] open Default: 1
	Time Step Adjustment	floating point number	`DELAY`	Choosing a lower value will result in a better numerical precision but also in a longer calculation time.	Minimum: 0.010000 Maximum: 1.000000 Default: 0.500000
	Surrounding Air Temperature	floating point number	`T_AIR`	Surrounding air temperature [degree Celsius].	Minimum: -273.150000 Default: 15.000000
	Cold Air Temperature	floating point number	`T_AIR_COLD`	Cold air temperature [degree Celsius].	Minimum: -273.150000 Default: 5.000000

Command Line


Usage: saga_cmd sim_air_flow 0 [-DEM ] [-PRODUCTION ] [-PRODUCTION_DEFAULT ] [-FRICTION ] [-FRICTION_DEFAULT ] [-AIR ] [-VELOCITY ] [-RESET ] [-TIME_STOP ] [-TIME_UPDATE ] [-EDGE ] [-DELAY ] [-T_AIR ] [-T_AIR_COLD ]
  -DEM:                  	Elevation
	grid, input
  -PRODUCTION:           	Production
	grid, input, optional
  -PRODUCTION_DEFAULT:	Default
	floating point number
	Minimum: 0.000000
	Default: 1.000000
  -FRICTION:             	Surface Friction Coefficient
	grid, input, optional
  -FRICTION_DEFAULT:  	Default
	floating point number
	Minimum: 0.000000
	Default: 1.000000
  -AIR:                  	Cold Air Height
	grid, output
  -VELOCITY:             	Velocity
	grid, output, optional
  -RESET:                	Reset
	boolean
	Default: 1
  -TIME_STOP:         	Simulation Time [h]
	floating point number
	Minimum: 0.000000
	Default: 6.000000
  -TIME_UPDATE:       	Map Update Frequency [min]
	floating point number
	Minimum: 0.000000
	Default: 10.000000
  -EDGE:                 	Edge
	choice
	Available Choices:
	[0] closed
	[1] open
	Default: 1
  -DELAY:             	Time Step Adjustment
	floating point number
	Minimum: 0.010000
	Maximum: 1.000000
	Default: 0.500000
  -T_AIR:             	Surrounding Air Temperature
	floating point number
	Minimum: -273.150000
	Default: 15.000000
  -T_AIR_COLD:        	Cold Air Temperature
	floating point number
	Minimum: -273.150000
	Default: 5.000000