Inlet formula (Water Overlay): Difference between revisions
mNo edit summary |
mNo edit summary |
||
| Line 50: | Line 50: | ||
* Δw = The amount of water flow which takes place. | * Δw = The amount of water flow which takes place. | ||
== | ==Related== | ||
The following topics are related to this formula. | |||
===Structures=== | |||
* [[Inlet (Water Overlay)|Inlet]] | * [[Inlet (Water Overlay)|Inlet]] | ||
===Models=== | |||
== | |||
* [[Surface model (Water Overlay)|Surface model]] | * [[Surface model (Water Overlay)|Surface model]] | ||
{{Template:WaterOverlay_nav}} | {{Template:WaterOverlay_nav}} | ||
{{Water Module buttons}} | {{Water Module buttons}} | ||
Revision as of 07:25, 19 June 2019
Inlets are hydraulic structures can pump water in and out of the project area and are connected with a water body outside the project area.
The amount flowing in or out of inlets is calculated for the cell the inlet resides on.
Case 1: Inlet:
When calculating inlets, first the capacities are calculated.
If a lower threshold Tl,t is defined:
- Qlth = max( 0 , Tl,t - wt )
If a positive inlet q Qt is defined:
- Qt = Δt * Qt
If a capacity Qtotal is defined:
- Qc = Qtotal- ΣQ0..t-1
After calculating the capacities, the actual water inflow is calculated. If any of the terms are undefined, they are not included.
- Δw = max( 0 , min( Qlth , Qt , Qc ) ) / A
Case 2 Outlets:
When calculating outlets, first the capacities are calculated.
If an upper threshold Tu,t is defined:
- Quth = min( 0 , Tu,t - wt )
If a negative inlet q Qt is defined:
- Qt = Δt * Qt
If a capacity Qtotal is defined:
- Qc = -Qtotal - ΣQ0..t-1
After calculating the capacities, the actual water ouflow is calculated. If any of the terms are undefined, they are not included.
- Δw = min( 0 , max( Quth , Qt , Qc) ) / A
Where:
- wt = The water level on the surface relative to datum, at time t.
- Tl,t = The LOWER_THRESHOLD of the inlet at time t.
- Tu,t = The UPPER_THRESHOLD of the inlet at time t.
- qt = The INLET_Q of the inlet at time t.
- Δt = Computational timestep.
- Qtotal = The INLET_CAPACITY of the inlet.
- Q0..n = The calculated previous amounts of flow.
- Qlth = The desired lower water level at the inlet's location, based on the LOWER_THRESHOLD of the inlet.
- Quth = The desired upper water level at the outlet's location, based on the outlet's UPPER_THRESHOLD of the inlet.
- Qt = The amount of water inflow (or outflow when negative) possible based on the INLET_Q of the inlet and timestep Δt.
- Qc = The total amount of water inflow (or outflow when negative) allowed based on the total capacity of the inlet.
- A = Size of the inlet/outlet area in m2, based on the amount of cells and cell size. Current implementation only has one cell.
- Δw = The amount of water flow which takes place.
Related
The following topics are related to this formula.
Structures
Models
