Page 32 - Continuous Process Modeling Quick Start Guide
P. 32

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Continuous Process Quick Start Guide
Configure the Line Chart block
Options tab
On the block’s Options tab, enter the following text in the “Column labels” box to give more meaningful headings to the table (be sure to include the semi-colon): Month;Rainfall (inches)
Enter Rainfall as the label for the block
Click OK to save changes and close the block’s dialog.
Random Number block that represents water from the stream
In this model, the Random Number block is used to specify a random distribution of water entering the reservoir from the stream. The distribution is a real number between 0 and 1, indicating that the stream will add between 0 and 1 inches of water to the reservoir’s level each month.
Open the Random Number block’s dialog.
It happens that the settings are the same as the assumptions for this model:
Distribution: Uniform Real (default) Minimum: 0 (default)
Maximum: 1 (default)
Label the block Stream. Click OK to close the dialog.
Math block
As indicated by the plus sign on its icon when you placed the block in the model, the Math block is set by default to add its inputs.
Label the block Add and close its dialog.
Holding Tank block that represents the reservoir
The Holding Tank block represents the level of water in the reservoir. The assumptions state that the Holding Tank has no beginning contents and does not release any of its contents.
Open the Holding Tank block’s dialog. In the Options tab, set:
Initial contents: 0 (default)
Inputs are: integrated (delay) Label the block Reservoir. Click OK.
☞ Since the values are based on time, the Holding Tank should be set to integrate, rather than sum, its inputs. This will output the value at time 1 that has been calculated for the period from time 0 to 1. Integration for continuous simulations is discussed more thoroughly on page 38.
Configure the Line Chart block
As this model is constructed, the Line Chart will report the level of water in the reservoir.


































































































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