A monthly-pattern demand node allows you to describe a demand as monthly values in megalitres. This is a simple representation supporting the needs of demand and supply analysis. The demand from nodes is accumulated in a bottom-up pass to the identified supply storage, from which water is released (if possible) at the appropriate time to meet the demand. You can configure the model by right-clicking Demand Models and choosing Monthly Pattern from the contextual menu (Figure 1). Next, specify the monthly demands in ML.
Figure 1. Water User node (Monthly Pattern, Demand)
You can enter monthly demand values directly or load the data from a file. Table 1 shows the format of a comma-separated (.CSV) file for importing monthly demand data. For simulation over smaller time-steps, the monthly volume is evenly distributed across the time-steps for that month.
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| Note: For a monthly pattern demand model, orders are in units of ML, and are averaged over an entire month for a daily value. To ensure that there is no discrepancy in orders between leap and non-leap years, define a time series demand model with a function as the input data source. Then, add a pattern variable with daily units to allow Source to recognise the number of days in February. As an example, consider the data input for a water user demand model which has been assigned a function ($Function1), which in turn is a variable of type time series ($ts). Figure 2 shows the time series variable and Figure 3 depicts the input function assigned to the demand model. |
Figure 2. Time series demand model, Time series variable
Figure 3. Time series demand model, Input function
| Refer to the Time Series Demand model for more information. |
Refer to Return flows for configuring Return flows in the model.
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