Process Control Using a PID Controller

Application ID: 866

This model shows how a flow model can be coupled to a process control mechanism.

Controlling application parameters according to other application parameters is important within process engineering. Most control mechanisms use the data at a wall or an outlet to control inlet parameters. More accurate control can occur if you can control inlet parameters due to data found within a component or piece of equipment.

This model couples mass transfer to fluid flow with two inlets (one controlled) and a PID controller. In this case, fluid flow is controlled according to the concentration at a point within the geometry - therefore a requirement for a physical model.

The model makes use of Projection variables in order to couple the Ordinary differential equation of the PID controller to the concentration point and the inlet velocity.

This model example illustrates applications of this type that would nominally be built using the following products:

COMSOL Multiphysics®