This component is a control valve that can be used for the process regulation, as a manual valve or as an expansion valve. It takes into account reverse flow.
| Pos | PORTS_LIB.analog_signal | (n = 1) | IN | Massflow signal (%) | |
| f_in | fluid | IN | |||
| f_out | fluid | OUT | |||
| feedback | PORTS_LIB.analog_signal | (n = 1) | OUT | feedback position (%) |
| Cv | REAL | 11.8 | Valve flow coefficient for completely open position | - | |
| Rv | REAL | 50 | Flow range of valve at constant drop | - | |
| dP_lam | REAL | 0.001 | Pressure diffence for laminar flow | bar | |
| tau | REAL | 0.0001 | Time constant of mass flow filter | s | |
| type | ENUM ValveType | Isopercentual_valve | Type of valve | - | |
| zeta | REAL | 1.3 | Equivalent loss coefficient | - |
| Av | REAL | Valve flow coefficient metric | m^2 | ||
| Av0 | REAL | Valve flow coefficient metric for completely open position | m^2 | ||
| G | REAL | Mass flow per unit area for molecular flow | kg/(s�m^2) | ||
| Gcr_in | REAL | Critical mass flow per unit area | kg/(s�m^2) | ||
| dP | REAL | Pa | |||
| dP_loss | REAL | Pressure loss | Pa | ||
| m | REAL | Mass flow, positive from f_out to f_in | kg/s | ||
| pos | REAL | Commanded valve position | % | ||
| pos_com | REAL | Commanded valve position | % | ||
| pressure | REAL | Pressure | bar | ||
| rho | REAL | Pressure | kg/m^3 | ||
| u | REAL | Stem position | - |
It transmits information from the inlet port to the outlet port about the working fluid that is being used in the fluid loop, the calculation option (real fluid) and checks if there is a working fluid defined in the model.
The valve actuator is modeled with a simple delay in the commanded position:
where pos_com is the value of the valve commanded by the control system limited to the range 0-100.
pos_com = max(0, min(100, Pos.signal[1]) )
Document generated automatically with EcosimPro Version: 5.4.14 Date: 2015:02:02 Time: 12:52:59