Selection of valves with different characteristics (depending on type and construction of the valve) with and without positioning dynamics (first order exponential lag with time constant tau. The valve characteristics are implemented according to the relations given in Thomas P. (1999), Simulation of Industrial Processes For Control Engineers, Butterworth-Heinemann, Oxford, UK.
The minimum valve travel xmin (stroke of valve actuator piston) is set by default to a small value, to prevent complete closure of the valve. This, in order to prevent potential problems at simulation execution time. For certain system structures, the value of xmin can be set to zero if desired.
| Name | Description |
|---|---|
| ValveLinearCharacteristicNoDynamics | Valve with linear characteristic. |
| ValveLinearCharacteristic | Valve with linear characteristic and exponential first order lag dynamics |
| ValveEqualPercentageCharacteristic | Valve with equal percentage characteristic and exponential first order lag dynamics |
| ValveButterflyCharacteristic | Valve with butterfly characteristic and exponential first order lag dynamics |