Valve 1 - Dynamic Simple
NOTE: This method is not available in Build138 or later.
This page is for project running under
Network solution - Dynamic and Flow Calculation - Simple mode.
The valve model will deliver flow based on the user specified capacity and opening position. In this mode, the pressure is ignored.
For Dynamic Transfer mode, please refer to Valve1.
The diagram shows the default drawing of the Valve, with the required connecting streams. The unit will not operate unless all of the above streams are connected.
The physical location of the connections is not important; the user may connect the streams to any position on the drawing.
Inputs and Outputs
|Number of Connections||Description|
|Input||Required||In||1||1||Input stream to valve.|
|Output||Required||Out||1||1||Output stream from valve.|
The valve is a constant enthalpy process.
Step 1) Enthalpy can be calculated from the inlet conditions.
Step 2) Outlet temperature can be calculated from enthalpy and outlet pressure.
Summary of Data Sections
- Valve-1 tab - Contains general information relating to the unit.
- VLE - Optional tab, only visible if the VLEquilibrium is enabled in the Evaluation Block.
- Info tab - Contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
- Links tab, contains a summary table for all the input and output streams.
- Audit tab - Contains summary information required for Mass and Energy balance. See Model Examples for enthalpy calculation Examples.
Dynamic Valve1 Page
Unit Type: Valve-1 - The first tab page in the access window will have this name.
|Tag / Symbol||Input / Calc||Options||Description/Calculated Variables|
|Common Data on First Tab Page|
|Qm||Calc||The total mass of material flowing through the valve.|
|Qv||Calc||The total volumetric flow of material flowing through the valve.|
|NQv||Calc||The normalised volumetric flow through the valve. The volume is calculated at Normal Temperature and Pressure (NTP), default values are 25C and 101.325kPa. This is only relevant for flows containing vapours.
NTP can be specified by the user in the configuration file (see Project Configuration).
|T||Calc||The temperature of material flowing through the valve.|
|Rho||Calc||The density of material flowing through the valve.|
|NRho||Calc||The density of material of material flowing through the valve at Normal Temperature and Pressure (NTP).|
|PiEst||Calc||The estimated Pressure at the inlet of the valve.|
|Pi||Calc||The actual pressure at the inlet of the valve.|
|dP||Calc||the pressure change in the valve.|
|Po||Calc||The actual pressure at the outlet of the valve.|
|PoEst||Calc||The estimated Pressure at the outlet of the valve.|
|VLEquilibrium||List box||Vapour Liquid Equilibrium (VLE) is enabled here. If this is 'On' then the associated page, VLE becomes visible and may be configured. |
Note: This option may automatically adjust the species make-up.
|Group||Default||Using the valve group of equations.|
|AsMass||Tickbox||On||Allows the user to enter the valve Capacity in mass flow, Qm.Rqd will be settable.|
|off||Allows the user to enter the valve Capacity in volumetric flow, Qv.Rqd will be settable.|
|Qm.Rqd||Input/Calc||AsMass=On||The required valve Capacity in mass flow if the valve is 100% opened.|
|Qv.Rqd||Input/Calc||AsMass=off||The required valve Capacity in volumetric flow if the valve is 100% opened.|
|CapacityCtrl||List Box||Off||NOTE in Dynamic Simple mode this has no effect|
|ByMass||NOTE in Dynamic Simple mode this has no effect|
|ByVolume||NOTE in Dynamic Simple mode this has no effect|
|Eqn.Nominal... NOTE THIS SECTION HAS NO EFFECT ON DYNAMIC Simple MODE|
|Method||List Box||None||No pressure drop|
|Liner||Linear Pressure drop - NOTE in Dynamic Simple mode this has no effect|
|EqualPerc||Pressure drop with pressure drop proportional to flow - NOTE in Dynamic Simple mode this has no effect|
|QuickActing||Pressure drop based on user specified data - NOTE in Dynamic transfer Simple this has no effect|
|DP||Input||The required pressure drop when the valve is opened.|
|Qm||Input/Calc||AsMass=On||Used to work out pressure drop required (above) when the valve is opened.|
|Qv||Input/Calc||AsMass=Off||Used to work out pressure drop required (above) when the valve is opened.|
|Type||List Box||Position||Allows the control of the valve on/off and % opened.|
|Pos & Stroke||Allows valve to ramp up to its opening position in the specified valve opening time|
|Stroke Opn/Cls||Allows the valve to ramp up/down on opening position during open and close, instead of reaching its full opening in one single iteration.|
|Mode||List Box||Active||Displays minimum fields for normal operation of the valve|
|Command(Latch)||Displays additional fields for control of the valve, usually used when connecting to PLC or operating Systems|
|Command(State)||Displays additional fields for control of the valve, usually used when connecting to PLC or operating Systems|
|Postion, the following field is visible with this mode.|
|On||Tickbox||Toggles the valve on/off|
|N/C||Tickbox||No backward flow allowed|
|Actual||Calc||The actual valve % opened.|
|Reqd||Input||The required valve % opened.|
|OpenCmd||Tickbox||Signals the valve to open, usually used when connecting to PLC or operating Systems|
|CloseCmd||Tickbox||Signals the valve to close, usually used when connecting to PLC or operating Systems|
|LatchCmds||Tickbox||Latch command, usually used when connecting to PLC or operating Systems|
|LatchState||Input||Latch state, usually used when connecting to PLC or operating Systems|
|Open||Feedback||confirms the valve is opened, usually used when connecting to PLC or operating Systems|
|Closed||Feedback||confirms the valve is closed, usually used when connecting to PLC or operating Systems|
|Manual||Input||Used to override the valve opening, used mainly in control logic / PLC testing.|
|MinOpening||Input||Sets the valve Min % opened limit.|
|MaxOpening||Input||Sets the valve Max % opened limit.|
|LeakOpening||Input||Sets the valve Leak % opened limit.|
|Physical||Feedback||The actual valve opening|
|Stroke Opn/Cls - Command(Latch) or Command(State), the following extra fields are visible with this mode. Usually used when connecting to PLC or operating Systems|
|Permissive||Tickbox||Toggles the valve on/off|
|OpenCmd||Tickbox||Sends the valve open signal|
|CloseCmd||Tickbox||Sends the valve close signal|
|OpenInvert||Tickbox||Sends the valve open invert signal ??|
|CloseInvert||Tickbox||Sends the valve close invert signal ??|
|Pos & Stroke, the following extra fields are visible with this mode.|
|StrkTime||Tickbox||The time it will take for the valve to get to its required % opening|
|Stroke Opn/Cls, the following extra fields are visible with this mode.|
|CloseTime||Input||The time it will take for the valve to close.|
|LoOpen||Feedback||Signals the valve is at low opening position if it is less or equal to the LoOpenLimit|
|HiOpen||Feedback||Signals the valve is at high opening position if it is greater or equal to the HiOpenLimit|
|LoOpenLimit||Input||Sets the valve's low open position limit|
|HiOpenLimit||Input||Sets the valve's high open position limit|
Adding this Model to a Project
Insert into Configuration file
Sort either by DLL or Group.
See Model Selection for more information on adding models to the configuration file.
Insert into Project
See Insert Unit for general information on inserting units.