# Valve 1 - Dynamic Simple

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## General Description

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.

### Diagram

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

 Label RequiredOptional InputOutput Number of Connections Description Min Max. Input Required In 1 1 Input stream to valve. Output Required Out 1 1 Output stream from valve.

## Model Theory

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.

## Data Sections

### Summary of Data Sections

1. Valve-1 tab - Contains general information relating to the unit.
2. VLE - Optional tab, only visible if the VLEquilibrium is enabled in the Evaluation Block.
3. Info tab - Contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
4. Links tab, contains a summary table for all the input and output streams.
5. 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). QmPrvPB Calc ?? 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. Eqn... 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. Posn... 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 ReverseAction Tickbox ?? 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 ActMemory Tickbox ??? PowerSupply... Source List Box The power supply can be specified via Menu Command View - Power Supplies, depending on the option selected on the Power Supply page, the power can be on/off. This can be used to trip valves if required. Available Default Returns the status of the power supply. Load... PowerFactor Input The power factor used to estimate the shaft power. ShaftPower Input Estimates the ShaftPower based on the Power Factor and flow through the valve.

## Adding this Model to a Project

Insert into Configuration file

Sort either by DLL or Group.

 DLL: Piping1.dll → Units/Links → Piping: Valve(1) or Group: Mass Transfer → Units/Links → Piping: Valve(1)