Valve 1 - Dynamic Simple

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Valve 1 in Steady State and Dynamic Transfer Push Mode	Valve 1 in Dynamic Transfer Pull Mode	Valve 1 - Dynamic with Simple Flow Calculation Mode

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General Description

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.

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	Required Optional	Input Output	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		???

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)

See Project Configuration for more information on adding models to the configuration file.

Insert into Project

Insert Unit

→

Piping

→

Valve(1)

See Insert Unit for general information on inserting units.