Process Control: Modeling, Design, and Simulation

M15.1. Motivating Example

Consider the control schematic diagram for the flow control loop shown in Figure M15-1. In practice, this loop contains a number of components, as detailed in Figure M15-2.

Figure M15-1. Schematic instrumentation diagram for a flow controller.

Figure M15-2. More detailed instrumentation diagram for a flow controller.

We can see that this loop consists of the following components.

• Flowmeter— often an orifice plate meter. The volumetric flow rate is proportional to the square root of the pressure drop across the orifice plate ...