WQ Distribute Inflow

This category of methods is applicable to the layered methods only. These methods define how the incoming water from the Inflow and side flows (for example, canal flow, hydrologic inflow, and so on) is distributed into the reservoir. For example, it may be a function of density, temperature, and so on, and may be allocated into one or more of the reservoir layers.

None

This is the default method and is not a valid method for calculation. An error is flagged if this method executes. It does not instantiate any water quality slots.

By Temperature

No slots are explicitly instantiated by this method but the following slots are used as a part of the calculation.

Slots With Required Known Data

• Total Inflows

• Temperature—This method requires a current total inflow temperature, a previous epilimnion temperature, and a previous hypolimnion temperature, all are columns of the Temperature Agg Series Slot.

Slots With Output Data

• Inflow to Epilimnion

• Inflow to Hypolimnion

Method Details

The distributeInflowbyTemp method compares the average total inflow temperature and distributes the total inflow based on a simple linear weighting scheme. In general, if the temperature is between the temperatures of the epilimnion and hypolimnion, the total inflow is split by a linear ratio of the total inflow temperature to the temperature difference between the two layers. If the total inflow temperature is greater or less than both layer’s temperatures, the total inflow is totally allocated to the layer with the more similar temperature.

The following is more detail on the algorithm. Only one of the following options will be selected by the algorithm

• If previous epilimnion and hypolimnion temperatures are very close (within 0.1C) distribute the total inflow to each layer based on previous layer volumes.

• If the Total Inflow Temperature is greater than the previous epilimnion temperature, distribute all of the Total Inflow to the top layer, the epilimnion.

• If Total Inflow Temperature is less than the previous hypolimnion temp, distribute all of the Total Inflow to the bottom layer, the hypolimnion.

• If Total Inflow Temperature is between the previous epilimnion and hypolimnion temperatures, distribute the Total Inflow using a weighted ratio based on previous layer temperatures and the current Total Inflow Temperature.

Specify Distribution

Distributes the Total Inflow based on the values in either the Inflow to Hypolimnion or Epilimnion slots. One and only one of these must be specified or an error occurs.

No slots are explicitly instantiated by this method, but the following slots are used as a part of the calculation:

• Total Inflows

• Inflow to Hypolimnion

• Inflow to Epilimnion

Specify Fraction

Allows you to distribute the inflows using a series of fractions.

Slots Specific to This Method

Inflow to Hypolimnion Fraction

Type: Series with Periodic Input

Units: Fraction

Description: Fraction of the total inflow that enters the Hypolimnion

Information: The value must be specified and the value must be between 0 and 1, inclusive.

I/O: Required via input or Rules

Links: Not linkable

Method Details

The distribution is computed as follows:

(14.3) Inflow to Hypolimnion = Inflow to Hypolimnion Fraction * Total Inflows

(14.4) Inflow to Epilimnion = Total Inflows - Inflow to Hypolimnion;

Revised: 01/05/2024