Pipe - Dynamic Mode

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Navigation: Models -> General Models -> Pipe - Dynamic Mode

Related Links: Pipe

NOTE: This page is valid for SysCAD 9.2 Build 132 and later.


General Description

This section is for the Pipe model when used in Dynamic Transfer mode. For help on the Pipe model in Steady State mode, please see Pipe.

This is used to transfer material between two units in SysCAD. Each pipe can have only one source and one destination. The user will find that a large amount of information is contained in pipe.

In Dynamic Transfer mode pipes may be configured either as Transfer Push or Transfer Pull. The user may set the transfer mode on the Info tab of the pipe:

  • In Transfer Pull mode Local networks are established, and this will determine the flow through the individual pipes.
  • In Transfer Push mode the pipes act as chutes where flow is instantaneously transferred from the source to the destination unit.
  • Please see Dynamic Transfer Modes for more information on Transfer Push and Transfer Pull modes.

Note: The user only needs to set the transfer mode for any selected pipe in the Local Network - all other pipes in this Local network will copy this transfer mode.

Flowchart

The following shows the sequence of events if a Pipe is not simplified and any sub model options are enabled.

Pipe - Dynamic non simplified.jpg


Data Sections

Summary of Data Sections

The pipe access window may consist of a number of sections. This number may increase or decrease, based on user configuration and / or number of species.

  1. Pipe-1 - The first tab displays a summary of the flow information in the pipe, the Source and Destination connections of the pipe.
  2. Settings - The second tab allows the user to change the pipe settings. To enable the sub models, for example Reactions or Environmental Heat Exchange, in a Pipe, the user must first disable Simplify and then the Evaluation Block (EB) will be visible.
  3. Qo - This and subsequent tab pages, e.g. Qo.. and Sp, shows the properties of the outlet stream. This tab is always visible. If any sub-models have been enabled, then these values are AFTER they have been completed (see the Flowchart above).
  4. Qi - This and subsequent tab pages, e.g. Qi.. and Sp, shows the properties of the inlet stream. This tab is only visible if Simplify is NOT enabled. If any sub-models have been enabled, then these values are BEFORE they have been completed (see the Flowchart above).
  5. RB - Optional tab that is visible if Reactions are enabled.
  6. EHX - Optional tab that is visible if Environmental Heat Exchanger is enabled.
  7. Evap - Optional tab that is visible if Evaporator is enabled.
  8. VLE - Optional tab that is visible if Vapour Liquid Equilibrium is enabled.
  9. MU - Optional tab, or tabs if there is more than one Makeup, that is visible if Makeups are enabled.
  10. Sz & MSz - Optional tabs that are visible if Size Distribution is used.
  11. Info tab - contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
  12. MP tab - Optional tab, only visible if Procedures have been enabled on the Info tab page.
  13. Links tab, contains a summary table for all the input and output streams.
  14. Audit tab - contains summary information required for Mass and Energy balance. See Model Examples for enthalpy calculation Examples.

Unit Type: Pipe-1 - The first tab page in the access window will have this name.

Pipe-1

Symbol / Tag

Input / Calc

Description

Common Data on First Tab Page

Results: Flow Conditions

MassFlow / Qm Calc The total mass of material flowing through the pipe.
VolFlow / Qv Calc The total volumetric flow through the pipe.
VolFlow / NQv Calc The normalised volumetric flow through the pipe. 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).
TemperatureIn / Ti Calc The temperature of the material flowing into the pipe.
TemperatureOut / To Calc The temperature of the material flowing out of the pipe.
Temperature / T Calc The temperature of the material flowing into the pipe.
Density / Rho Calc The density of the material flowing into the pipe.
NDensity / NRho Calc The normalised density of the material flowing through the pipe. The normalised density 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).
Press_Input / Pi Calc The pressure into the pipe.
Press_Output / Po Calc The pressure out of the pipe.

Connections

Source_Link / SrcIO Display The Source connection of the pipe, i.e. material from this unit flows into the pipe.
Destination_Link / DstIO Display The Destination connection of the pipe, i.e. material from the pipe flows into this unit

Transfer Pull Mode

TN... - This section is only visible in Transfer Pull Mode
SourceCount Calc The number of possible sources where material is available.
QmAvail Calc The total amount of material available from all sources
QmAvailNR Calc The total amount of material available (not restricted) from all sources
AvailRho Calc The density of material available, used to calculate the volumetric flowrate
FreeCount Calc
QmDemand Calc The total demanded mass flow from downstream process
LinkPull Calc

Settings

Tag / Symbol Input/ Calc Description

Options

Flow.On Tick Box The default state is on. This variable can be used to disable the pipe. No material will be allowed to flow through the pipe if the box is not checked.
Simplify Tick Box By default this state is enabled, causing the pipe to be a 'simple' pipe with only the Qo tabs being visible. If the user wishes to set anything in the pipe or enable reactions, heat loss, etc, then this tick box must be disabled. Additional fields will then become visible and the user may set sub-models in the pipe.
Show.Qi Tick Box This tickbox is only visible if Simplify is disabled. The user may enable this to view both the Qi (flow into the pipe) and Qo (flow out of the pipe) tabs, which may be useful if the user has added reactions, heat exchange, etc to the pipe.
CollectStats Tick Box Statistics section described below will be visible if this is enabled. This allows the user to collect statistics on the pipe flow during a run.
FwdOnly Tick Box If this is enabled then flow may only occur in the Forward direction through the pipe.
Direction (This is used for SimpleP pipes, where simple pressure networks are used) Default Material will flow in either direction through the pipe, as required by the network.
Forward Material may only flow in the Forward direction.
Reverse Material may only flow in the Reverse direction.

FC(FlowCapacity)

This section is visible in Transfer mode only.

CapacityControl List Box Off - The maximum mass flow through the pump will be set to unlimited amount (uncontrolled)
ByMassFlow - The maximum mass flow through the pump
ByVolumeFlow - The maximum volumetric flow through the pump
Qm.RqdCapacity / Qm.Capacity Input Visible when ByMassFlow option is selected. The required pump Capacity in mass flow if the pump is operating at 100% speed.
Qv.RqdCapacity / Qv.Capacity Input Visible when ByVolueFlow option is selected. The required pump Capacity in volumetric flow if the pump is operating at 100% speed.
Qm.MinCapacity / Qm.MinCap Input Visible with the ByMassFlow method. The minimum user specified flow capacity by mass.
Qm.MaxCapacity / Qm.MaxCap Input Visible with the ByMassFlow method. The maximum user specified flow capacity by mass. Enter * for unlimited flow.
Qv.MinCapacity / Qv.MinCap Input Visible with the ByVolumeFlow method. The minimum user specified flow capacity by volume.
Qv.MaxCapacity / Qv.MaxCap Input Visible with the ByVolumeFlow method. The maximum user specified flow capacity by volume. Enter * for unlimited flow.
MeasRho Display The stream density used when converting between mass and volume flows.
OverCapacity Spill If more material enters the pipe then the Maximum Capacity value, then the excess material will be 'spilled' and sent to the Spills area.
Accept If more material enters the pipe then the Maximum Capacity value, then the pipe must accept the excess material.
BatchMethod None The Batch functionality is not enabled.
Total Mass The Batch functionality is enabled and the required batch size is defined in terms of Mass flow. Further fields will become visible if this option is selected allowing the user to set the required batch mass.
Total Volume The Batch functionality is enabled and the required batch size is defined in terms of Volume flow. Further fields will become visible if this option is selected allowing the user to set the required batch volume.
The following fields will be visible if Total Mass is selected as the Batch method.
M.BatchAddition Input The Mass of the required Batch. This amount of material will be allowed to flow out of the pipe at the rate specified in Qm.Capacity or Qv.Capacity.
When this value is set the amount of material will be added to the amount of material already in M.BatchRemaining (the field below), and then this field will revert to 0.
M.BatchRemaining Calc / Input The Mass of material currently in a Batch, i.e. the amount of material in a Batch that still has to flow through the pipe. Normally this value is initialised at the start of a run and then it is calculated by SysCAD from the amount required in M.BatchAddition and the amount already delivered by the batch.
However, the user may set this value and hence override the calculated Batch amount at any stage.
If the users sets this as Undefined (or '*') this is equivalent to any infinite Batch and therefore the flow through the pipe will not be restricted.
M.BatchTotal Display The Total Mass that has flowed through the pipe using the Batch addition method.
The following fields will be visible if Total Volume is selected as the Batch method.
V.BatchAddition Input The Volume of the required Batch. This amount of material will be allowed to flow out of the pipe at the rate specified in Qm.Capacity or Qv.Capacity.
When this value is set the amount of material will be added to the amount of material already in V.BatchRemaining (the field below), and then this field will revert to 0.
V.BatchRemaining Calc / Input The Volume of material currently in a Batch, i.e. the amount of material in a Batch that still has to flow through the pipe. Normally this value is initialised at the start of a run and then it is calculated by SysCAD from the amount required in V.BatchAddition and the amount already delivered by the batch.
However, the user may set this value and hence override the calculated Batch amount at any stage.
If the users sets this as Undefined (or '*') this is equivalent to any infinite Batch and therefore the flow through the pipe will not be restricted.
V.BatchTotal Display The Total Volume that has flowed through the pipe using the Batch addition method.
The following fields will be visible if Total Mass or Total Volume is selected as the Batch method.
BatchState None No Batch mode has been set.
Inactive A Batch method has been selected, but the Batch is undefined.
Busy A Batch method has been selected, there is material remaining in the Batch, and hence there is flow in the pipe due to the Batch.
Stop Flow A Batch method has been selected, there is NO material remaining in the Batch, and hence there is no flow in the pipe, i.e. the Batch will prevent any flow in the pipe.
BatchUsePreset Tickbox This enables the use Preset for the Batch amount.
M or V.BatchUsePreset Input The Mass or Volume of the Batch when the model is Preset. Refer to Preset for more information.

EB (Flow Evaluation Block)

This is only visible if Simplify is NOT enabled.

EvalSequence Display The sequence in which the sub models (which are part of the evaluation blocks) will be calculated. The user may either set the required sequence of the individual sub-models, or use the AutoSequence option to allow SysCAD to set the sequence. The autosequence is: 1st Makeup, 2nd Reactions, 3rd EHX and 4th VLE.
Makeups Input The number of Makeup Blocks required. Extra dropdown options Makeup1, Makeup2, etc will be added to allow these to be switched on and off and prioritised in relation to the other sub-models.
MakeupX List Use to enable or disable and set the sequence of the Makeup Block in relation to the other sub-models. If this is 'On' then the associated page, MUX becomes visible and may be configured.
Note: This field is only visible if the entry for 'Makeups' is greater then 0. If there is one makeup then X=1. If there are two makeups, then X=1 and X=2, etc.
Reactions List Reaction Block (RB) - Enable or disable Reactions and set the sequence in relation to the other sub-models. If this is 'On' then the associated page, RB becomes visible and may be configured.
Note: The user does not have to configure a reaction file, even if this block is checked.
EnvironHX List Environmental Heat Exchanger (EHX) - Enable or disable Heat Exchange and set the sequence in relation to the other sub-models. If this is 'On' then the associated page, EHX may become visible and may be configured.
Note: The user does not have to configure an environmental heat exchange, even if this block is checked.
Evaporation List Evaporation Block (Evap) - Enable or disable the Evaporator and set the sequence in relation to the other sub-models. If this is 'On' then the associated page, Evap may become visible and may be configured.
Note: The user does not have to configure an evaporator, even if this block is checked.
VLEquilibrium List Vapour Liquid Equilibrium (VLE) - Enable or disable Vapour Liquid Equilibrium and set the sequence in relation to the other sub-models. 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 in Qo.

Pressure Drop

Note In SysCAD 9.2 this section is only visible if Simplify is Disabled. Not available in Dynamic Simple Mode.

Press_Mode None There is no pressure change in the pipe.
Fixed_Drop The user can enter a fixed pressure drop in the pipe. The default is 0.
Fixed_Boost The user can enter a fixed pressure boost in the pipe. The default is 0.
Darcy_DP The pressure change will be calculated using the Darcy equation.
Const_Src_P The user can type in a fixed pressure value.
Diameter_Velocity The user may specify a velocity and SysCAD will calculate a pipe diameter to give the required velocity.
Note: SysCAD does NOT calculate a pressure drop for this method.
dP Calc The calculated pressure change across the pipe, based on the method selected by the user. This value will be zero for the 'None' and 'Diameter_Velocity' methods.
Pdrop Calc The calculated pressure drop across the pipe, based on the method selected by the user. This value will be zero for the 'None' and 'Diameter_Velocity' methods.
This value will always have the opposite sign to dP above.
The following field is only visible if either the Fixed_Drop or Fixed_Boost method is selected.
Fxd_DP Input Allows the user to enter a change in pressure value. This may be positive to emulate a Pump, or negative to emulate pressure drop due to flow.
The following field is only visible if the Const_Src_P method is selected.
Lnk_P_Src Input Allows the user to specify the outlet pressure from the pipe.
The following fields are only visible if the Diameter_Velocity method is selected.
Diam Display The estimated nominal diameter of the pipe based on the user defined Velocity.
Velocity / Vel Input The user defined target velocity, SysCAD will estimate the required Pipe diameter needed to achieve this required velocity.
Pdrop Calc This is not used.
The following fields are only visible if the Darcy_DP method is selected.
Diam Input The Inner diameter of the pipe.
ScaleBuildUp Input The build up of material inside the pipe, thus reducing the ID of pipe. For a clean pipe, this value = 0.
K_Method Calc K Calculate K from user defined values.
Define_K Calculates the pressure drop using user specified pressure drop factor.
K_Value Input / Calc The pressure drop factor: K = f * L/D. If the Define_K method is selected, this is an input, otherwise it is calculated.
The following fields are visible if Calc_K method is selected.
Length Input Sum of the actual and fitted length of the pipe.
f_Method Calc_f Calculate the friction factor from user defined values.
Define_f The user can define a friction factor (f) to be used
FricFac Input The Darcy friction factor (f). Please note this is equivalent to (4) times Fanning's friction factor. Visible if Define_f method is selected.
Viscosity Input The Viscosity of the material flowing through the pipe. Visible if Calc_f method is selected.
Pipe_Rough Input The Pipe Roughness value. Visible if Calc_f method is selected.
Re Calc The calculated Reynolds number. Visible if Calc_f method is selected.
FricFac Calc The calculated Darcy friction factor (f). Visible if Calc_f method is selected. Please note this is equivalent to (4) times Fanning's friction factor.
K_MinorLosses Input K value for minor pressure losses in the pipe.
Velocity / Vel Calc The velocity in the pipe.
Note: a warning will be given if the velocity in the pipe is too high. Velocity limits maybe set/adjusted via View-PlantModel-Settings Tab. See Range Checks

End Points

SrcHFrc Input/ Display The height, as a fraction, of the pipe from the Source unit. This may be set by the user only if the Source unit is a Tank. For all other units, this is a display field.
DstHFrc Input/ Display The height, as a fraction, of the pipe into the Destination unit. This may be set by the user only if the Destination unit is a Tank. For all other units, this is a display field.

Tear

Each Recycle loop will contain a single Tear stream. SysCAD will identify the best stream to 'tear' and normally the user does not have to change any settings. However, the user may manually set tear streams, if required.

Priority Normal SysCAD determines the priority of the stream in the network and if the stream should be a tear stream and its solving order.
First The user may force the stream order to be first in the network.
Last The user may force the stream order to be last in the network.
RqdType No Tear No manual tear is required.
Manual Tear This option is used when the user does not want to use the system defined tear stream. This will force SysCAD to set this pipe as a Tear stream and the system defined tear stream in the recycle loop will be reset to have no tear.
Break This option is used when the user want to 'break' the stream and manually set some parameters in the stream outlet.
State No Tear The stream has no tears or breaks.
Zero Flow Tear The stream is a Tear stream with zero flow.
System Tear SysCAD has analysed the network and determined that the stream is a Tear stream because it is part of a recycle loop and is the most efficient stream to tear.
Manual Tear The user has manually set this stream as a Tear stream.
Break The user has manually 'broken' the stream.
Flange Display The relevant flange that will have the tear status. In SysCAD each pipe is connected using flanges and these will store the tear information.
AdjQmToEstQm Tickbox If this is enabled then the mass flow from the pipe will be forced to be equal to the estimated mass flow.

Statistics

This section will only be visible if the CollectStats tick box is enabled in Options section.

Reset_Stats Button The user may click on this button to reset all of the statistics for this pipe back to zero.
Time Display The total time during which the statistics have been collected.
TotalMass / Mass Display The total mass that has flowed through the pipe during the measured time.
MassFlow_Average / QmAvg Display The average Mass flow through the pipe during the measured time.
ZeroFlowTime / TimeNoQm Display The total time during which there has been no flow through the pipe.
FlowTime / TimeQm Display The time during which there has been non-zero flow through the pipe.
On_Average / OnQmAvg Display The average Mass flow through the pipe for the time when there has been non-zero flow, i.e. periods of zero flow are not included in this calculation.
Min_MassFlow / QmMin Display The minimum Mass flow through the pipe during the measured time.
Max_MassFlow / QmMax Display The maximum Mass flow through the pipe during the measured time.
TotalVol / Volume Display The total volume that has flowed through the pipe during the measured time.
VolFlow_Average / QvAvg Display The average Volume flow through the pipe during the measured time.
SolidMass / SMt Display The total Solids mass that has flowed through the pipe during the measured time.
SolidMassFlowAvg / SQmAvg Display The average Solids mass that has flowed through the pipe during the measured time.
LiquidMass / LMt Display The total Liquids mass that has flowed through the pipe during the measured time.
LiquidMassFlowAvg / LQmAvg Display The average Liquids mass that has flowed through the pipe during the measured time.
TotalQmCapacity / CapMT Display The total Mass Capacity of the pipe during the measured time.
CapMassFlowAvg / CapQmAvg Display The average required Mass Capacity of the pipe during the measured time.
CapUtilisation / CapUtil Display The Mass Capacity of the pipe that has been utilised during the measured time.

Hints and Comments

  1. The user must ensure that the View and Phase options will display the required variables. e.g. if the concentration of H2SO4(aq) is required, then the View would be 'CompntConc' and Phase should be 'Liquid'. If Phase is 'All', then the model calculates the acid concentration using the volume of solids, liquids and vapours.