Page 137 - ExtendSim User Guide
P. 137

Making connections and running the simulation
If you have manually placed the blocks on the worksheet, they need to be connected to indicate the flow of items and values:
Connect the blocks’ item connectors as follows:
From the Create block’s item output to the Queue’s item input From the Queue’s output to the Activity’s input
From the Activity’s output to the Exit’s input
☞ There are two ways to connect Item library blocks that are already in a model. One is to draw a connection line from the item output of one block to the item input of the other as discussed in the tutorial on page 28. The other method is to Bump Connect the blocks. To Bump Connect, touch one block’s item input to another block’s item output and release. ExtendSim will estab- lish the connection and space the blocks.
So that the model will display results, connect the following value connectors: From the top (total exited) value output on the Exit to the top Plotter input From the L (queue length) value output on the Queue to the second Plotter input
Reposition the blocks as desired. Note that ExtendSim will anticipate how you want the connection lines between Item connectors to behave. For more information, see “Auto route connection lines” on page 799. This feature can be disabled in the Edit > Options > Model tab.
Save the model. Run the simulation.
Verifying results
This is a good opportunity to verify the results. Because the model has random numbers your results will differ slightly, but the plotter graph should be similar to the picture at the right.
At the end of the simulation, the plotter might show that
80 cars have been washed and that there are around 40
cars waiting to be washed. This would correspond to the
information in the Create block, which shows that about
120 cars were generated. These numbers make sense
considering that 1 car is generated approximately every 4 minutes and the simulation runs for 480 minutes.
Animating the model
You don’t have to animate the model, but it is sometimes helpful to see the process in action. In the Create block’s Item Animation tab:
Tutorial 111
A basic discrete event model
Discrete Event


































































































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