View source for Piping System Model

[[Category:Models]] [[Category:Dynamic]] [[Category:Control]]
{{Navigation|[[Models]]|[[Models#Pressure Changing Models|Pressure Changing Models]]}}

----
{{TOC}}
== General Description ==

The Piping System Model is used in dynamic projects with Transfer mode.  It allows the user emulate a full piping system, including Pumps, Valves, Pipe lengths, etc. in a single Piping System model.  The user specifies the number and type of sub-units in the piping system and can configure each sub-unit individually.  The user must configure the individual sub-units within the Piping System Model so that they comprise a reasonable system.

The piping system model calculates the pressure drop across each sub-unit, and hence across the entire system.  

If required it will also calculate the estimated flow through the system, consistent with specified inlet and outlet pressures. This estimated flow can be used to set a Capacity Tag upstream of the Piping System inlet to
make the inlet flow equal to the calculated flow.

The available sub-units in a Piping System Model are: 
* '''Head''' - Elevation Head - the head due to the height of the liquid at the start of the piping system;
* '''Pipe''' - pipe lengths and fittings  can be included - the pressure drop in the pipe due to change of height, friction losses, etc. will be calculated;
* '''Orifice ''' - pressure reduction / flow restriction.
* '''[[Pump 2|Pump2]]''' - pressure boost provided by a pump; and
* '''[[ Valve 2|Valve2]]''' - pressure drop provided by a valve.

'''Notes'''
# If the flow entering the Piping System comes from a Tank with ''WithStaticHead'' selected, a '''Head''' sub-unit should not be selected.
# The Pump and the Valve have control settings that the user may dynamically change.  These settings will change the calculated pressure drop of the system.
# The Piping System Model will NOT automatically adjust the flow, but can be set to calculate the estimated flow through the system.  This estimate can then be used to set the actual flow in the system, if required.
# The Piping System Model is designed to emulate an entire piping length, without any split flows.
# The Piping System Model requires a single input and a single output and will not operate unless both of these 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 ==

{| border="1" cellpadding="5" cellspacing="0"  
|- 
| valign="top" rowspan="2" | '''Label''' || valign="top" rowspan="2" | '''Required<br>Optional''' || valign="top" rowspan="2" | '''Input<br>Output ''' ||  colspan="2"   | '''Number of Connections''' || valign="top" rowspan="2" | '''Description'''
|- 
|  '''Min''' || '''Max''' 
|-
| Input || Required ||  In || 1 || 1 || Input stream to Piping System Model.
|-
| Output || Required ||  Out || 1 || 1 || Output stream from Piping System Model.
|}

== Model Theory ==

For Valve and Pump theory please see:
* [[Valve 2#Model Theory|Valve Theory]] and
* [[Pump 2#Model Theory|Pump Theory]].

== Data Sections ==

The default access window consists of the following sections: 
# '''[[#Piping System Page|PipingSystem]]''' tab - Allows the user to insert sub-units and displays the calculated results.
# '''[[#Control|Control]]''' tab - Allows the user to set any valve positions and Pump speeds.
# '''[[Piping System Model#Settings|Settings]]''' tab - Allows the user to specify the sub-unit methods and enter the required data.
#{{ShowQout|Feed|feed}}
#{{ShowQout|Prod|product}}
# '''[[Common Data Sections#Common Data on Info Tab Page|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 Table|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.

===Piping System Page===
'''Unit Type: PipingSystem''' - The first tab page in the access window will have this name.

{|   border="1" cellpadding="5" cellspacing="0" 
|-
|'''Tag (Long/Short)'''||'''Input / Calc'''||'''Description/Calculated Variables / Options'''
{{Common Data on First Tab Page}} 
|-
|  colspan="3" font style="background: #ebebeb"    |
'' Requirements ''
|-
| On || Tick Box || This allows the user to disable the unit.  If the unit is ''Off'' then the pressure drop across the unit = 0.
|-
|  colspan="3" font style="background: #ebebeb"    |

=== Options (Flow Estimate Calculations) ===
|-
| valign="top" rowspan="2" | FlowEstimateMethod || None || The user does not wish to calculate the estimated of the flow through the unit. The pressure drop WILL be calculated. If this option is selected, no other options will be visible.
|-
| Simple || The flow through the unit will be calculated with no time delays or transient effects.  This is useful for short piping systems.
<!--
|-
| User Damping || The flow through the unit will be calculated with a time delay, or transient effect.  The user may set the fraction of damping required. '''CURRENTLY UNUSED.'''
|-
| Length Damping || The flow through the unit will be calculated with a time delay, or transient effect, based on the length of the piping system.  This is useful where the user wishes to emulate a long pipeline so that a change in feed pressure does produce an instantaneous flow change in the pipe system.  '''CURRENTLY UNUSED.'''
|-
| DampingRate || Input || Visible if ''User Damping'' is the Flow Estimate Method selected. The required amount of damping on the estimated flow.  0% represents no damping (changes are instantaneous - so equal to using ''Simple''), and 99% represents large damping.  '''CURRENTLY UNUSED.'''
-->
|-
| MaxiumFlowEstimate / QmMaxEst || Input || User estimate of the maximum flow rate through the Piping System. If no value is specified, 10000 t/h is used.
|- 
| valign="top" rowspan="4" | InletPressureMethod || FeedPipePressure || Inlet pressure to the Piping System is the exit pressure from the upstream Pipe.
|-
| Value || User specified inlet pressure.
|-
| Tag || Tag whose value is to be used as the inlet pressure
|-
| AtmosphericPressure || Inlet pressure is the Project Atmospheric Pressure.
|-
| PressureIn.Val || Input || Visible if ''Value'' is the Inlet Pressure Method selected. The required inlet pressure.
|-
| PressureInTag || Input || Visible if ''Tag'' is the Inlet Pressure Method selected. The Tag from which the required inlet pressure is to be read.
|-
| PressureInTag.Meas || Display || Visible if ''Tag'' is the Inlet Pressure Method selected. The required inlet pressure read from the Tag.
|- 
| valign="top" rowspan="3" | OutletPressureMethod || AtmosphericPressure || Outlet pressure is the Project Atmospheric Pressure.
|-
| Value || User specified outlet pressure.
|-
| Tag || Tag whose value is to be used as the outlet pressure
|-
| PressureOut.Val || Input || Visible if ''Value'' is the Outlet Pressure Method selected. The required outlet pressure.
|-
| PressureOutTag || Input || Visible if ''Tag'' is the Outlet Pressure Method selected. The Tag from which the required outlet pressure is to be read.
|-
| PressureOutTag.Meas || Display || Visible if ''Tag'' is the Outlet Pressure Method selected. The required outlet pressure read from the Tag.
|-
| SetCapacity || Tick Box || The user may choose to set the inlet flow as the flow estimate by setting a Capacity Tag upstream of the Piping System inlet.
|-
| CapacityTag || Input || Visible if ''SetCapacity'' is ticked. The tag whose value is to be set to the flow estimate. This should be a ''Qm.Capacity'' tag in a Pipe or Tank.
|-
| CapacityTag.Meas || Display || Visible if ''SetCapacity'' is ticked. The required inlet flow, which should be equal to the ''QmEst'' value for the Piping System.
|-
| DampingRate || Input || Visible if ''User Damping'' is the Flow Estimate Method selected. The required amount of damping on the estimated flow.  0% represents no damping (changes are instantaneous - so equal to using ''Simple''), and 99% represents large damping.  '''CURRENTLY UNUSED.'''
|-
|  colspan="3" font style="background: #ebebeb"    |
=== Sub-unit Selection ===
[[File:piping System2.png]]
|- 
| SegmentCount || Input || The user may define the number of sub-units in the Piping System Model.  For example, if a system consists of a Valve, Pump, Valve and pipe then the number of sub-units, or segments = 4.
|- 
| ReNumber || Button || This re-numbers all of the sub-units so that they are all in ascending order.
|-
|  colspan="3" font style="background: #ebebeb" |'' Segment Specification ''
|- 
| Type || List || The user may choose any of the sub-units that are available, i.e. Head, Pipe, Valve or Pump.
|- 
| Insert || Button || The user may insert a new sub-unit above the current sub-unit.  This will automatically increase the Segment Count.  The default sub-unit that is inserted is a Pipe, but the user may change this by selecting any of the available sub-units from the drop down list.
|- 
| Remove || Button || The user may remove the sub-unit from the Piping System Model.  This will automatically decrease the Segment Count.
|- 
| Up || Button || The user may move the current sub-unit up in the order of sub-units.  The sub-unit number will NOT change, i.e. Pipe3 can be moved above Pipe1.  The user may click on the ''ReNumber'' button to automatically number the sub-units in ascending order.
|- 
| Down || Button || The user may move the current sub-unit down the order of sub-units.  The sub-unit number will NOT change, i.e. Pipe1 can be moved below Pipe2.  The user may click on the ''ReNumber'' button to automatically number the sub-units in ascending order.
|-
|  colspan="3" font style="background: #ebebeb"    |'''Options'''
{{ShowQout DataSection|Feed|feed}}
{{ShowQout DataSection|Prod|product}}
|-
|  colspan="3" font style="background: #ebebeb"    |
=== Results ===
|-
|  colspan="3" font style="background: #ebebeb" |'' Overview ''
|-
| Feed.MassFlow / Feed.Qm || font style="background: #ebebeb"| Display || The mass flow through the Piping System Model.
|-
| Feed.Temperature / Feed.T || font style="background: #ebebeb"| Display || The inlet temperature to the Piping System Model.
|-
| Feed.Pressure / Feed.P || font style="background: #ebebeb"| Display || The inlet pressure to the Piping System Model.
|-
| Sub-unit(i).Po || font style="background: #ebebeb"| Calc || The pressure from sub-unit(i), where this could be Head, Valve, Pump, orifice or Pipe.  The pressure from each sub-unit will be displayed.
|-
| Prod.Pressure / Prod.P || font style="background: #ebebeb"| Calc || The exit pressure from the Piping System Model.
|-
| Prod.Temperature / Prod.T || font style="background: #ebebeb"| Calc || The exit temperature from the Piping System Model.
|-
| Work|| font style="background: #ebebeb"|Calc||The actual work done. Some segment type has work term (such as pump2).
|-
| HeatFlow|| font style="background: #ebebeb"|Calc||The total heat flow.  Some segment types allow (such as pipe) allow heat flow to be added.
|-
|  colspan="3" font style="background: #ebebeb" |'' Totals ''
|-
| Sub-unit(i).PressChange / Sub-unit(i).dP || font style="background: #ebebeb"| Calc || The pressure change across sub-unit(i), where this could be Head, Valve, Pump or Pipe.  The pressure change across each sub-unit will be displayed.
|-
| PressChange / dP || font style="background: #ebebeb"| Calc || The total pressure change across the Piping System Model.
|-
| PressDrop / PDrop || font style="background: #ebebeb"| Calc || The pressure drop across the entire Piping System Model.
|-
| PressBoost / PBoost || font style="background: #ebebeb"| Calc || The pressure boost across the entire Piping System Model.
|-
| Closed || font style="background: #ebebeb"| Tick Box || If this is True, then a sub-unit, either a Valve or Pump, is set to 0% and is the flow estimate = 0.
|-
| Head || font style="background: #ebebeb"| Calc || The calculated Head from the Piping System Model.
|-
| HeightChange || font style="background: #ebebeb"| Calc || The calculated change in Height across the Piping System Model (-ve indicates a drop from Feed to Product)
|-
|  colspan="3" font style="background: #ebebeb" |'' Relative Heights ''
|-
| Feed || font style="background: #ebebeb"| Calc || The relative height of the feed to the Piping System Model.
|-
| Sub-unit(i).Out || font style="background: #ebebeb"| Calc || The relative height of sub-unit(i), where sub-unit can be Head or Pipe.  All Head and Pipe sub-units will be displayed.
|-
| Prod || font style="background: #ebebeb"| Calc || The relative height of the product of the Piping System Model.
|-
|  colspan="3" font style="background: #ebebeb" |'' Flow Estimate '' These fields are only visible if the user has selected a Flow Estimate method.
|-
| MassFlow / Qm || font style="background: #ebebeb"| Display || The actual mass flow through the Piping System Model.
|-
| QmEstState || font style="background: #ebebeb"| Display || The state of the Piping System Model estimate.  This lets the user know what state the model is in, i.e. OK, No Flow, sub-units closed, etc. 
|-
| ExtraTarget.Pi || font style="background: #ebebeb"| Calc || Inlet pressure used in estimate
|-
| ExtraTarget.Po || font style="background: #ebebeb"| Calc || Target outlet pressure Used in estimate
|-
| ExtraTarget.PressChange / ExtraTarget.dP || font style="background: #ebebeb"| Calc || The extra pressure drop required IF the user has specified a Target Exit Pressure from the unit. (dPinValue - dPoutValue)
|-
| WeightedTotalK || font style="background: #ebebeb"| Calc || The calculated resistance, or loss coefficient value, K, of the Piping System Model. (Sum of diameter weighted pipe K factors)
|-
| TotalHead.PressChange / TotalHead.dP || font style="background: #ebebeb"| Calc || The total pressure change across the Piping System Model.  (Due to static head (Head, Pipe) and Pump dP)
|-
| DiamUsed || font style="background: #ebebeb"| Calc || The piping diameter used to calculate the velocity and estimated flow through the Piping System Model. (Reference diameter for weighting)
|-
| ZeroFlow.Po || font style="background: #ebebeb"| Calc || Estimated outlet pressure at zero flow: static head + pump boost
|-
| MassFlowEst / QmEst || font style="background: #ebebeb"| Display || The estimated mass flow through the Piping System Model.
|-
| VolFlowEst / QvEst || font style="background: #ebebeb"| Calc || The estimated volumetric flow rate through the Piping System Model.
<!--
|-
| VelocityEst || font style="background: #ebebeb"| Calc || The estimated velocity in the Piping System Model.
|-
| PrevVelEst || font style="background: #ebebeb"| Calc || The velocity in the Piping System Model estimated in the previous iteration.  (This is only useful if Damping is used.)
-->
|-
|SystemHasCharacteristic|| font style="background: #ebebeb"| Tick Box ||
|-
|SystemIsStable|| font style="background: #ebebeb"| Tick Box ||

|}

=== Control ===

If the user selected either a Pump or a Valve as one of the sub-units and a controlled mode for either of these, then this tab will allow these units to be controlled.

{|   border="1" cellpadding="5" cellspacing="0" 
|width=150|'''Tag (Long/Short)'''||'''Input / Calc'''||'''Description/Calculated Variables / Options'''
|-
|  colspan="3" font style="background: #ebebeb"    | '''Segment xx (Valvex - Description)'''
{{Valve2 Control Data section}}
|-
|  colspan="3" font style="background: #ebebeb"    | '''Segment xx (Pumpx - Description)'''
{{Pump2 Control Data section}}
|}

=== Settings === 

The user must configure each sub-unit that is specified on the first tab.  

Please see '''[[Valve 2#Settings|Valve Settings]]''' and '''[[Pump 2#Settings|Pump Settings]]''' for the configuration of the Valves and Pumps.

The settings for Heads and Pipes are described below.

{|   border="1" cellpadding="5" cellspacing="0" 
|width=150|'''Tag (Long/Short)'''||'''Input / Calc'''||'''Description/Calculated Variables / Options'''
|-
|  colspan="3" font style="background: #ebebeb"    | '''Head'''
|-
| On || Tick Box || This allows the user to disable the Head.  If the Head is ''Off'' then Head = 0.
|-
| EquipID || Input || This field is optional.  The user may type in an unique ID for this, example ''Head Tank''.
|-
| Height / H || Input || The actual Elevation Head required.  This calculates the pressure boost due to elevation as material enters the Piping System.
|-
|  colspan="3" font style="background: #ebebeb"    | '''Pipe'''
|-
| On || Tick Box || This allows the user to disable the Pipe.  If the Pipe is ''Off'' then pressure drop across the pipe = 0.
|-
| EquipID || Input || This field is optional.  The user may type in an unique ID for the Pipe.
|-
| valign="top" rowspan="4" | OpType || Fixed dP || The user specifies a fixed pressure change across the Pipe.  This will be independent of flow.
|-
| Fixed Drop || The user specifies a fixed pressure drop across the Pipe.  This will be independent of flow.
|-
| Fixed Boost || The user specifies a fixed pressure boost across the Pipe.  This will be independent of flow.
|-
|Darcy || Use the Darcy equation to calculate pressure drop.  With this method pressure drop is a function of flow.
|- 
| DeltaHeight / dH || Input || The required height difference between the pipe entry and exit.  A negative values indicates that the exit is lower than the entry.
|-
|  colspan="3" font style="background: #ebebeb"    | ''Fixed dP Fixed Drop and Fixed Boost'' - The following field is visible for these three modes.
|- 
| Fixed.dP/Drop/Boost || Input || The required pressure change, drop or boost (depending on the mode selected) across the Pipe.
|-
|  colspan="3" font style="background: #ebebeb"    | ''Darcy''  The following fields are visible with this mode.
|- 
| Diameter / Diam || Input || The required '''internal''' pipe diameter.
|- 
| ScaleBuildup / Scale || Input || The required scale build up thickness in the pipe.  Note, this values will be multiplied by 2 and then used to decrease the actual internal diameter of the Pipe.
|- 
| MinorK || Input || The K value for any fittings on the pipe.
|-
| valign="top" rowspan="4" | KMethod || User Pipe K || The user specifies a K value for the pipeline.
|- 
| Length and Friction F || The user specifies the pipe length and a friction factor.  SysCAD will then calculate the equivalent K value.
|-
| Length, Colebrook FricF || The user specifies the pipe length, Viscosity and roughness.  SysCAD will then calculate the friction factor using the Colebrook equation.
|-
| Length, Churchill FricF || The user specifies the pipe length, Viscosity and roughness.  SysCAD will then calculate the friction factor using the Churchill equation.
|-
|  colspan="3" font style="background: #ebebeb"    | ''User Pipe K''  The following field is visible if this method is chosen.
|-
| UserPipeK || Input || The required K value for the Pipe.
|-
|  colspan="3" font style="background: #ebebeb"    | The following 2 fields are visible for the other methods.
|-
| Length / L || Input || The required Pipe Length.
|-
| FittingsLength / FitL || Input || The equivalent pipe fittings Length.  <br>Please do not include a value here for fittings if they are already included under ''MinorK''.
|-
|  colspan="3" font style="background: #ebebeb"    | ''Length and Friction F'' The following field is visible for this method.
|-
| UserFricFactor / UserFricF || Input || The required friction factor.
|-
|  colspan="3" font style="background: #ebebeb"    | ''Length, Churchill and Colebrook Friction Factor'' The following fields are visible for both of these methods.
|-
| Viscosity || Input || The viscosity of the material flowing through the pipe.
|-
| Roughness || Input || The roughness of the pipe.
|-
|  colspan="3" font style="background: #ebebeb"    | '''Valve'''
{{Valve2 Setting Data Section}}
|-
|  colspan="3" font style="background: #ebebeb"    | '''Pump'''
{{Pump2 Setting Data Section}}
|-
|  colspan="3" font style="background: #ebebeb"    | '''Orifice'''
|-
| On || Tick Box || This allows the user to disable the Orifice.  If the Orifice is ''Off'' then dP= 0.
|-
| EquipID || Input || This field is optional.  The user may type in an unique ID for the Orifice.
|-
| valign="top" rowspan="6" | OpType || User K Value || The user specifies a fixed K value
|-
| K0 value per BS1042  || Uses KO value as per BS1042, Methods for the Measurement of Fluid Flow in Pipes Part 1 - Orifice Plates, Nozzles and Venturi Tubes.
|-
| Plate || modelled as orifice plate, returns K value
|-
|Nozzle|| modelled as flow nozzle, returns K value
|-
|Square Edge|| modelled as Square Edge orifice, returns K value
|-
|Round Edge|| modelled as Round Edge orifice, returns K value
|- 
| Diameter / Diam || Input || The required pipe inside diameter.
|- 
| OrificeDiameter / OrifDiam || Input || The orifice diameter.
|-
| DiameterRatio/Beta || Input || The ratio of orifice diameter / pipe inside diameter.
|- 
| MinorK || Input || K factor for fittings
|-
|UserValveK || Input || Visible with OpType =  User K Value.   The K value for the orifice.
|-
| Viscosity || Input || The viscosity of the material flowing through the Orifice.
|}

== Adding this Model to a Project ==

{{Adding Model to a Project | DllName=Piping2 | DllSubGroup=Piping | UnitOp=Piping System | Group=Mass Transfer}}

== Example - Entering Elevation Information ==
:[[File:piping System.png]]
*Feed_Tank - Assume at 0 m elevation
*Feed_Pump - '''Piping System''' : Seg08 (Pipe8 - Pipe to Head tank) has delta height (dH) of 15 m
:[[File:piping System2.png]]
*Head_tank - Assume at 15 m elevation (tank height 2m)  -  NOTE that we can't enter an elevation for the tank here, so we need to provide the information in the next unit where the change of height occurs.
*FCV_001 - '''Piping System''' : Flow control valve to Area1 (See first picture above)
**Head - 16.7m  (this reflects the elevation head from head_tank, assuming tank is 85% full ) - this will calculate the pressure at the start of the FCV_001 piping system.
**Destination elevation is 5m higher