Item To Flow

Overview and Key Concepts

The Item To Flow is designed to interface between FloWorks objects and FlexSim's discrete objects. It receives discrete flow items from a fixed resource and converts it into flow. An example of a real-life process represented by a Item To Flow could be an unpacking machine that converts discrete packs into continuous bulk material.

The input side of the item to flow is similar to a fixed resource sink, while the output side looks like a regular FloWorks object. You can specify an outflow rule, maximum outflow rate and a fluid amount per entering item. This amount is specified as an expression, which can yield a different result for each flow item.

The visual representation of the item to flow includes a progress bar and in the statistics of the object the progress of the emptying process of the current flow item is shown. The bar is a level indicator that fills to 100% when a flow item enters and gradually reduces, representing the amount of flow still to be sent before the next flow item is allowed to enter.

Events

The item to flow provides the On Rate Change event that fires whenever a change in the output flow rate occurs. In addition it has the following object specific events.

On Entering

This function is called when an item enters the item to flow object, regardless of whether it can start flowing or has items queued before it.

It has the following parameters:

Event Parameter Explanation
item A reference to the flow item that is entering the item to flow.
port The input port that the item is entering through.

On Entered

This function is called as soon as all the items queued before the current item have finished and the outflow corresponding to this item starts.

It has the following parameters:

Event Parameter Explanation
item A reference to the flow item that is entering the item to flow.
amount The outflow amount that has been determined for this item by the "Flowamount per item" expression.

On Item Empty

This function is called as soon as the outflow corresponding to an item has finished, immediately before the item will be removed.

It has the following parameters:

Event Parameter Explanation
item A reference to the flow item that will be destroyed immediately after this event.

States

For statistical purposes, the item to flow's FloWorks state profile will be in one of the following states at various points during a simulation run:

  • Idle - No flow is collected because there is no flow item, or because the output side is blocked, for example because the item to flow is waiting for downstream availability or an operator.
  • Generating - Flow is being released until the required amount to release an item has exited.

Properties

The item to flow object has five tabs with various properties. The first three tabs are standard tabs that are common to all flow objects. For more information about the properties on these tabs, see:

The last two tabs are the standard tabs that are common to all fixed resources. For more information about the properties on these tabs, see:

Settings

Control, flow arrows

These settings are described here.

Maximum item content

The maximum number of items that can be present in the item to flow simultaneously. Note that even when more than one item is present, only the first one will be flowing.

Flow Amount Per Item

You can enter an expression here which is evaluated every time a flow item enters the object. The result of this expression determines the amount of flow that will be released before the item is destroyed.

Triggers

The object specific triggers are described above under Events.

For more information about the remaining events see Fixed Resource - Events.

Custom coding

You may control the behavior of the item to flow dynamically by writing FlexScript, for example in a Script window or by changing the code behind one of the options in an object trigger.

The item to flow is an instance of the FlowObject class, see the class reference for information about its properties.