Objects
Agg Diversion Site
When solving given Diversion, (processSequential_givenDiversion and processLumped_givenDiversion) Incoming Available Water was removed from the required knowns in the dispatch conditions.This isn't necessary to solve. Also, Total Depletion, Total Diversion, and Total Unused Water were added to the potential governing slots.
See Solve Sequential given Total Diversion in Objects and Methods for more information.
Inline Power Plant
Inline Turbine Release and Bypass method
A new Inline Turbine Release and Bypass category was added to the Inline Power Plant. The default Specify Flows method uses the previous approach to compute the Bypass and Turbine Release. The new Flow Tables approach uses two new tables Flow vs Min Bypass and Flow vs Turbine Release. This method performs lookups to get the appropriate flow values. See Flow Tables in Objects and Methods for more information.
On the Flow vs Power Table, the zeroth column label has been changed from Turbine Release (or very old Inflow) to Flow to make it generic. Old models will be updated automatically. Any RPL expression that reference this column by name will need to be modified. See Flow vs Power Table in Objects and Methods for more information.
Power Reservoir
Peak Power with Off Peak Spill - New Slots
The following slots were added to the Peak Power Equation with Off Peak Spill power method.
• Minimum Elevation for Power Operations: This is an optional series slot with periodic input that provides elevation constraints that are applied within the HydropowerRelease RPL function. This function now computes the outflow necessary to get to the Minimum Elevation for Power Operations as part of the computation of the proposed outflow.
• Plant Power Limit: If the Plant Power Limit is valid and the computed power is greater than the Plant Power Limit, the power is reset to the Plant Power Limit. The Turbine Release and Energy are also cutback.
See Peak Power Equation with Off Peak Spill in Objects and Methods for more information.
Plant Power Equation - Additional Functionality
The following slots were added to the Plant Power Equation power method.
• Net Head vs Plant Efficiency: This slot is an alternative way to specify the plant efficiency. The method computes the efficiency as follows:
– If the 1X1 table slot Plant Efficiency Value is valid, it is used in all computations. This is the previous behavior and will not affect existing models.
– Otherwise, the Plant Efficiency Value is not valid, so the method interpolates the efficiency on the Net Head vs Plant Efficiency table using previous timestep Operating Head minus Head Loss.
• Plant Power Limit: If the Plant Power Limit is valid and the computed power is greater than the Plant Power Limit, the power is reset to the Plant Power Limit. The Turbine Release and Energy are also cutback.
See Level Power Reservoir in Objects and Methods for more information.
In addition, the Input Energy Adjustment category and Reduce Input Energy method are now available when the Plant Power Equation Release method is selected. If Energy is input and the resulting Turbine Release is greater than the maximum turbine release, the Max flag is set on Energy and the reservoir will recompute the maximum energy possible.
See Level Power Reservoir in Objects and Methods for more information on the Reduce Input Energy method.
Reach
Default Routing Method - No Routing
Previously the default method in the Routing category was No Method, which was actually an invalid method and would produce an error. Now the default method is No Routing, No Routing in Objects and Methods
Kinematic Reach Routing
On the Reach Routing category, there are now two versions of the Kinematic method:
• Kinematic: This is the original version of the Kinematic method as described Kinematic in Objects and Methods.
• Kinematic Improved: This modified version of the Kinematic method allows a smaller computational element length and reduces the mass balance error. It is described in more detail Kinematic Improved in Objects and Methods.
Reservoir
Allow Excess Specified Outflows
A new method Allow Excess Specified Outflow was added to the Input Outflow Adjustment category on the Reservoirs. This method allows you to specify (I or Z) an Outflow that is larger than the computed (Turbine) Release plus Spill. When this happens, the extra outflow is set on the new Outflow Exceeding Max series slot.
See Level Power Reservoir in Objects and Methods for more information.
Anticipated Storage Calculation
In the calculation of Anticipated Storage as part of the Cumulative Storage Value Table calculation in Simulation or Rulebased Simulation, if an intransit flow value (inflow on an upstream lagged reach) was missing, it could previously cause the run to abort with an error message. A missing intransit flow value could also result in the calculation of Anticipated Storage using Storage only without accounting for intransit water. Now a missing intransit flow value will result in Anticipated Storage remaining unsolved (NaN), and an informational diagnostic message will be posted in the User Methods diagnostic category. The run will no longer abort.
See Cumulative Storage Value Table in Objects and Methods for more information.
Heron Inflow calculation
The following changes were made to the Heron Inflow calculation Reservoir Account Slot Inflow method Heron Inflow in Accounting
• The Heron Inflow Values slot had the number of columns, column labels and units modified at one time. However, not all models had been converted to the new labels, and thus the old labels persisted in some model files:. A mechanism was added to check for the number of columns, column labels and units and correct them if necessary.
• The slots Heron Inflow Totals and Heron Cumulative Inflow Values columns with unit type of flow were changed to volume as these represent sums of flows.- Within the heronInflowCalc and findHeronRGInflow methods, cumulative values are now calculated as volumes rather than flows.
• A correction was made to the calculation of cumulNetGain when the inflow ratio is less than or equal to zero. Now the inflowRatio (which is negative or zero) is added. This actually cancels out any negative inflowRatio from the calculation of cumulNetGain (inflowRatio is subtracted in an earlier step). This change makes the calculation consistent with the analogous version in findHeronRGInflow. Note, this could change model results from previous versions.
K Factor Unit Type
The unit type was changed for the K Factor slot in the Pan and Ice Evap reservoir method from LengthPerTemperature_F to VelocityPerTemperature_F. These are automatically updated on model load and the scheme is set to display previously shown units. RPL expressions that reference this slot must be updated or unit type inconsistencies will occur.
Water User
Dispatch methods
In the solveSequential_givenDiversion and solveStandAlone_givenDiversion, Incoming Available Water was removed from the required knowns. This isn't necessary to solve. Also, Depletion and Outgoing Available Water were added to the potential governing slots.
For these two dispatch methods, the error checks if Diversion > Incoming Available Water and if Diversion > Diversion Requested were removed. These two checks made these dispatch methods unnecessarily restrictive.
This could affect existing models as it no longer errors in the above cases. Under certain situations, you could have additional results, but existing results should not be modified.
See Solve given Diversion in Objects and Methods for more information.
Specify Scheduled Requests
On the Water User, a new method was added to the Diversion and Depletion Request category called Specify Scheduled Requests. This method allows you to specify an initial scheduled amount (as either a series or periodic relationship) and then reduce the schedule to the requests. For more information, see Specify Scheduled Requests in Objects and Methods.
Revised: 01/05/2024