Pump 1 - Dynamic

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Navigation: Main Page -> Models -> Pressure Changing Models

Related Links: Pump 1 in Steady State and Dynamic Transfer Mode


General Description

This page is for project running under

Network solution - Dynamic and Flow Calculation - Simple mode.

The pump model will deliver flow based on the user specified capacity and running speed. In this mode, the pressure is ignored.


For Dynamic Transfer mode, please refer to Pump 1.

Diagram

Models-Pump-Image001.gif

The diagram shows the default drawing of the Pump, 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 pump.
Output Required Out 1 1 Output stream from pump.

Model Theory

From the first law of thermodynamics, the energy balance is:

[math]\mathbf{\mathit{Work = Enthalpy_{in} - Enthalpy_{out}}}[/math]

From the second law of thermodynamics:

[math]\mathbf{\mathit{Entropy_{in} = Entropy_{out}}}[/math]

Calculating Work:

Step 1) Enthalpy and Entropy in is calculated from the inlet stream Temperature and Pressure.

Step 2) Outlet Temperature and Enthalpy is calculated based on the Entropy and outlet pressure.

Step 3) Work is calculated from the difference in enthalpy.

Assumptions

  1. The process is in steady state and steady flow.
  2. The process is adiabatic.
  3. The change in Potential and Kinetics energy is ignored.
  4. The process is reversible and adiabatic

Data Sections

Summary of Data Sections

  1. Pump-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 Pump Page

Unit Type: Pump-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 pump.
Qv Calc   The total volumetric flow of material flowing through the pump.
NQv Calc   The normalised volumetric flow through the pump. 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 pump.
P Calc   The pressure of material flowing through the pump.
Rho Calc   The density of material flowing through the pump.
NRho Calc   The density of material of material flowing through the pump at Normal Temperature and Pressure (NTP).
 
Vf Calc   Vapour Mass Fraction at the inlet of the pump.
mVf Calc   Vapour Mass Fraction at the inlet of the pump.  ????
 
dPb Calc    ??
dPq Calc    ??
PiEst Calc   The estimated Pressure at the inlet of the pump.
Pi Calc   The actual pressure at the inlet of the pump.
dP Calc   the pressure change in the pump.
Po Calc   The actual pressure at the outlet of the pump.
PoEst Calc   The estimated Pressure at the outlet of the pump.
 
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 pump group of equations.
AsMass Tickbox On Allows the user to enter the pump Capacity in mass flow, Qm.Rqd will be settable.
off Allows the user to enter the pump Capacity in volumetric flow, Qv.Rqd will be settable.
 
Qm.Rqd Input/Calc AsMass=On The required pump Capacity in mass flow if the pump is operating at 100% speed.
Qv.Rqd Input/Calc AsMass=off The required pump Capacity in volumetric flow if the pump is operating at 100% speed.
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 boost
BoostFxd Fixed Boost - NOTE in Dynamic Simple mode this has no effect
BoostPDrop Pressure boost with pressure drop proportional to flow - NOTE in Dynamic Simple mode this has no effect
BoostOPPts Pressure boost based on user specified data - NOTE in Dynamic transfer Simple this has no effect
Boost Input   The required pressure boost when the Pump is running.
Method : BoostPDrop, the following field is visible with this mode.
Boost Input   The required pressure boost when the Pump is running.
DP Input   The required pressure drop (based on flow, Qm or Qv is specified below) when the Pump is running.
Qm Input/Calc AsMass=On Used to work out pressure drop required (above) when the pump is running.
Qv Input/Calc AsMass=Off Used to work out pressure drop required (above) when the pump is running.
Method : BoostOpPts, the following field is visible with this mode.
BstPt0 Input   The first point of the Boost pressure (based on 2-point linear relationship)
QmPt0 Input AsMass=On The corresponding Mass flow at the first point
QvPt0 Input AsMass=Off The corresponding Volumetric flow at the first point
BstPt1 Input   The second point of the Boost pressure (based on 2-point linear relationship)
QmPt1 Input AsMass=On The corresponding Mass flow at the second point
QvPt1 Input AsMass=Off The corresponding Volumetric flow at the second point
Speed...
Type List Box Power & Speed Allows the control of the pump on/off and speed.
Fwd Rev Allows the pump to operate in reverse
Soft Start Allows the pump to ramp up to its speed over time when started, instead of reaching its capacity in one single iteration.
Soft Start/Stop Allows the pump to ramp up/down during startup and shutdown, instead of reaching its capacity in one single iteration.
Mode List Box Simple Displays minimum fields for normal operation of the pump
Command(Latch) Displays additional fields for control of the pump, usually used when connecting to PLC or operating Systems
Command(State) Displays additional fields for control of the pump, usually used when connecting to PLC or operating Systems
Power & Speed - Simple, the following field is visible with this mode.
Run Tickbox   Toggles the pump on/off
Running Feedback   Returns the status of the pump
Tripped Tickbox   Use this to trip the pump.
Manual Input   Used to override the pump speed, used mainly in control logic / PLC testing.
Reqd Input   The required pump speed.
Actual Calc   The actual pump speed.
Regulated Calc   The regulated pump speed.
LoSpeed Feedback   Signals the pump is at low speed if speed is less or equal to the LoSpeedLimit
HiSpeed Feedback   Signals the pump is at high speed if speed is greater or equal to the HiSpeedLimit
LoSpeedLimit Input   Sets the pump low speed limit.
HiSpeedLimit Input   Sets the pump high speed limit.
AutoReStart Tick Box   Allows the pump to auto restart if the trip condition has be removed if this option is selected.
FailMode List Box None No Fail mode option.
NoStart Do not start when the pump has failed ??
NoStop Do not stop when the pump has failed ??
NoStartStop Do not start/stop when the pump has failed ??
RunMemory Default    ??
Power & Speed - Command(Latch) or Command(State), the following extra fields are visible with this mode. Usually used when connecting to PLC or operating Systems
Enable Tickbox   Toggles the pump on/off
Start Tickbox   Sends the pump start signal
Stop Tickbox   Sends the pump stop signal
StartInvert Tickbox   Sends the pump start invert signal
StopInvert Tickbox   Sends the pump stop invert signal
Fwd Rev, the following extra fields are visible with this mode.
Invert Tickbox   Toggles Invert signal
Forward Tickbox   Toggles Forward / Reverse
Soft Start, the following extra fields are visible with this mode.
StrtTime Input   The time it will take for the pump to get to its full speed.
MapLo Input    ??
MapHi Input    ??
Soft Start/Stop, the following extra fields are visible with this mode.
StopTime Input   The time it will take for the pump to stop.
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 pumps 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 pump.

Adding this Model to a Project

Insert into Configuration file

Sort either by DLL or Group.

 

DLL:

Piping1.dll

Units/Links

Piping: Pump(1)

or

Group:

Mass Transfer

Units/Links

Piping: Pump(1)

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


Insert into Project

 

Insert Unit

Piping

Pump(1)

See Insert Unit for general information on inserting units.