Pipe - Dynamic Mode
From SysCAD Documentation
Navigation: Models -> General Models -> Pipe - Dynamic Mode
Related Links: Pipe
NOTE: This page is valid for SysCAD 9.2 Build 132 and later.
Contents |
General Description
This section is for the Pipe model when used in Dynamic Transfer mode. For help on the Pipe model in ProBal (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 SimpleP or Transfer:
- In SimpleP simple pressure networks are established, and this will determine the flow through the individual pipes.
- In Transfer mode the pipes act as chutes where flow is instantaneously transferred from the source to the destination unit.
Flowchart
The following shows the sequence of events if a Pipe is not simplified and any sub model options are enabled.
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.
- Pipe-1 - The first tab displays a summary of the flow information in the pipe, the Source and Destination connections of the pipe.
- 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.
- Qo - This and subsequent tab pages, e.g. Qo.. and Qm, 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).
- Qi - This and subsequent tab pages, e.g. Qi.. and Qm, 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).
- RB - Optional tab that is visible if Reactions are enabled.
- EHX - Optional tab that is visible if Environmental Heat Exchanger is enabled.
- VLE - Optional tab that is visible if Vapour Liquid Equilibrium is enabled.
- MU - Optional tab, or tabs if there is more than one Makeup, that is visible if Makeups are enabled.
- Sz & MSz - Optional tabs that are visible if Size Distribution is used.
- 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 tab, only visible in SysCAD 9.2, 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.
Class: Pipe-1 The first tab page in the access window will have this name.
Pipe-1
|
Tag / Symbol |
Input / Calc |
Description |
Results: Flow Conditions | ||
| Qm | Calc | The total mass of material flowing through the pipe. |
| Qv | Calc | The total volumetric flow through the pipe. |
| 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). |
| Ti | Calc | The temperature of the material flowing into the pipe. |
| To | Calc | The temperature of the material flowing out of the pipe. |
| T | Calc | The temperature of the material flowing into the pipe. |
| Rho | Calc | The density of the material flowing into the pipe. |
| 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). |
| Pi | Calc | The pressure into the pipe. |
| Po | Calc | The pressure out of the pipe. |
Connections | ||
| SrcIO | Display | The Source connection of the pipe, i.e. material from this unit flows into the pipe. |
| DstIO | Display | The Destination connection of the pipe, i.e. material from the pipe flows into this unit |
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. | |
Flow CapacityThis section is visible in Transfer mode only. | ||
| 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. | |
| Flw... | ||
| AsMass | Tick box | If this is ticked then the user may set the Mass flow requirements. If this is NOT ticked then the user may set the Volume flow requirements. |
| The following fields are shown if AsMass is enabled. | ||
| Qm.Capacity | Input | The required mass flow through the pipe. |
| Qm.MinCap | Input | The minimum mass flow through the pipe. |
| Qm.MaxCap | Input | The maximum mass flow allowed through the pipe. If this field is left as the default of Undefined then there is no upper limit to the amount of material that can flow through the pipe. |
| The following fields are shown if AsMass is disabled. Note for all Qv capacities: As the density is not known before flow occurs, the volume flow capacity constraints are essentially one iteration behind as the previous iteration's density is used to determine the equivalent mass flow capacity. | ||
| Qv.Capacity | Input | The required volume flow through the pipe. |
| Qv.MinCap | Input | The minimum volume flow through the pipe. |
| Qv.MaxCap | Input | The maximum volume flow allowed through the pipe. If this field is left as the default of Undefined then there is no upper limit to the amount of material that can flow through the pipe. |
| MeasRho | Display | The measured density of the material flowing through the pipe. |
Batch RequirementsThis functionality allows the user to set discrete batch flows through the pipe. This section is visible in Transfer mode only. | ||
| 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. |
| 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. |
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. |
TearEach 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. |
StatisticsThis section will only be visible if the CollectStats tick box is enabled. | ||
| 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. |
| Mass | Display | The total mass that has flowed through the pipe during the measured time. |
| QmAve | Display | The average Mass flow through the pipe during the measured time. |
| TimeNoQm | Display | The total time during which there has been no flow through the pipe. |
| TimeQm | Display | The time during which there has been non-zero flow through the pipe. |
| OnQmAve | 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. |
| QmMin | Display | The minimum Mass flow through the pipe during the measured time. |
| QmMax | Display | The maximum Mass flow through the pipe during the measured time. |
| Volume | Display | The total volume that has flowed through the pipe during the measured time. |
| QvAve | Display | The average Volume flow through the pipe during the measured time. |
| SMt | Display | The total Solids mass that has flowed through the pipe during the measured time. |
| SQmAve | Display | The average Solids mass that has flowed through the pipe during the measured time. |
| LMt | Display | The total Liquids mass that has flowed through the pipe during the measured time. |
| LQmAve | Display | The average Liquids mass that has flowed through the pipe during the measured time. |
| CapMT | Display | The total Mass Capacity of the pipe during the measured time. |
| CapQmAve | Display | The average required Mass Capacity of the pipe during the measured time. |
| CapUtil | Display | The Mass Capacity of the pipe that has been utilised during the measured time. |
Hints and Comments
- 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.
