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Objects and Methods : Reservoir Methods : User Methods : Input Outflow Adjustment
Input Outflow Adjustment
This method category is only available if a method is selected in the Spill Calculation category. Its purpose is to adjust input Outflow values if they violate a physical constraint.
* None
This is the default method. It performs no calculations and there are no slots associated with it. The Outflow values will not be adjusted if this method is selected.
* Reduce Input Outflow
This method is used to reduce the input Outflow value whenever it exceeds the maximum reservoir outflow (due to outlet works capacity).
Slots Specific to This Method
 Requested Outflow
Type: Series Slot
Units: FLOW
Description: The Outflow value before being adjusted
Information: This slot is available so that the user can see when an Outflow value is adjusted. The value in this slot is the outflow value before being adjusted. A value exists in this slot only if the Outflow value is adjusted.
I/O: Output only
Method Details  
If the Outflow slot value is greater than the maximum reservoir outflow, this method saves the Outflow value in the Requested Outflow slot. Then, the Maximum Capacity flag is set on the Outflow slot. The reservoir is then forced to re-dispatch with the Outflow set to Max Capacity (instead of the original, input value). When the reservoir solves the second time, it computes the maximum reservoir outflow and sets this value on the Outflow slot. The Maximum Capacity flag remains on the Outflow slot for the timestep in question (and will be saved with the model file).
* Allow Excess Specified Outflows
This method allows input Outflows that exceed the maximum reservoir outflow (due to outlet capacity). Because the excess is above the maximum possible for the (Turbine) Release and Spill slots, it will not be classified as either. Instead, the excess is stored on a separate series slot for reporting or tracking.
Slots Specific to This Method
 Outflow Exceeding Max
Type: Series Slot
Units: Flow
Description: The portion of the input Outflow that exceeds the sum of the Spill and (Turbine) Release.
Information: This slot tracks the amount that does not fit through the Release and Spill structures.
I/O: Output only
Method Details  
Toward the end of each dispatch method, if Outflow is greater than the sum of Spill and (Turbine) Release, the Spill method is executed again to redistribute the Outflows to the appropriate spill structures. Within the Spill method, if there is still no room for the specified Outflow, the selected method in the Input Outflow Adjustment category is executed. When the Allow Excess Specified Outflows method is selected, it does the following:
1. If the Outflow does not have an input flag (I or Z), then the method exits and issues an error that there are excess outflows.
2. If the Outflow is input (I or Z flag), the method computes the difference between the specified Outflow and the maximum Outflow (that is, Turbine Release + Spill). This excess outflow is then set on the Outflow Exceeding Max slot.
3. The method then exits successfully and returns to the Spill method and then the dispatch method. The dispatch method sets the spill and mass balance slots.
Revised: 01/11/2023