Audit

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Model Tab Optional Input Content Tabs Optional Material Content Tabs Optional Material Flow Tabs Common Tabs
UnitType Content Section DSp Section Content Sp EC Qo Sp EC Info Links Table Audit

This page is for Build 139 or later. For Build 138 or earlier, please see Audit in 138.


Introduction

The details and values on the Audit tab page are only created after the SysCAD Solver has been started. It displays a summary of information required for mass and energy balance around the unit operation. This functionality can be enabled or disabled using the global Audit Options displayed at the top of each Audit page as well as on the Audit Tab Page of the Plant Model. If this is not required then this can be switched off which will provide a small improvement in solver speed.

Options

These are global settings. They can be set in any unit or on the Plant Model - Audit page.

Tag (Long/Short) Input / Calc Description
Options...
Audit.On Tickbox Switch the Total Mass and Energy Audit calculations on or off. If off, no Total Audit calculations will be performed or displayed. This option is for debugging and is always unticked on project load.
ElemAudit.On Tickbox Switch the Elemental Audit calculations on or off. If off, no Elemental Audit calculations will be performed.
AuditCheck.MassTol.Rel Display Relative tolerance for mass balance checks.
AuditCheck.MassTol.Abs Display Absolute tolerance for mass balance checks.
AuditCheck.HeatTol.Rel Display Relative tolerance for energy (heat) balance checks.
AuditCheck.HeatTol.Abs Display Absolute tolerance for energy (heat) balance checks.
Frequency
This setting determines when the
Audit tests are performed.
EveryIteration Only available in a steady state project. Audit calculations are carried out at every iteration.
EveryStep Only available in a dynamic project. Audit calculations are carried out at every step.
WhenSolved Only available in a steady state project. Audit calculations will only be carried out when the project is solved.
WhenPausedOrSolved Audit calculations will only be carried out when the solver is not busy, i.e. when the model is paused or stopped.
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Basics.ShowExtra Tickbox Only visible if Audit.On is enabled. Show Extended Audit Details on the Audit tab.
Streams.Collect Tickbox Only visible if Audit.On is enabled. Show Streams Audit Summary table on the Audit tab.
Elements.Collect Tickbox Only visible if Audit.On is enabled. Collect and show Elemental Audit Table on the AuditEl tab.
Elements.ShowExtra Tickbox Only visible if Elements.Collect is enabled. Show additional columns in the Elemental Audit Table on the AuditEl tab.
Species.Collect Tickbox Only visible if Audit.On is enabled. Collect and show Species Audit Table on the AuditSp tab.
Species.ShowExtra Tickbox Only visible if Species.Collect is enabled. Show additional columns in the Species Audit Table on the AuditSp tab.
Messages.OnError Tickbox Only visible if Audit.On and/or ElemAudit.On is enabled. Report audit errors to Messages Log in addition to Conditions window.
Pause.OnMassError Tickbox Only visible if Audit.On is enabled. Pause model if a mass balance error occurs. This option is for debugging and is always unticked on project load.
Pause.OnElemMassError Tickbox Only visible if ElemAudit.On is enabled. Pause model if an elemental mass balance error occurs. This option is for debugging and is always unticked on project load.
Pause.OnHeatError Tickbox Only visible if Audit.On is enabled. Pause model if a heat (energy) balance error occurs. This option is for debugging and is always unticked on project load.
Elements.DisplayTol.Rel Input Only visible if ElemAudit.On is enabled. Relative display tolerance for elemental mass imbalances.

Basic Audit

This table is only displayed if Audit.On is ticked.

Tag (Long/Short) Description
Basic Audit
Basics...
Mass.TotalIn (M1) Mass flow in, including from Makeup Blocks and Reaction Block Sources.
Mass.TotalOut (M2) Mass flow out, including via Discard Blocks and Reaction Block Sinks.
Mass.AccumRate (M3) Only visible in dynamic projects. Change in contents reported as an equivalent mass flow to/from content (surge).
Mass.Error Overall mass error (imbalance). For steady-state projects, = M2-M1. For dynamic projects, = M2 - (M1+M3).
Mass.RelError Overall relative mass error.
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TotalHeat.In (H1) Total Heat (energy) flowing in (Sensible + Heat of formation), including sources.
TotalHeat.Other (H2) Net Heat Gain in Unit Model including Sub-models (Reaction Block, EHX, etc.).
TotalHeat.Out (H3) Total Heat (energy) flowing out, including sinks.
TotalHeat.AccumRate (H4) Only visible in dynamic projects. Change in contents reported as an equivalent heat flow to/from content (surge).
TotalHeat.Change Total Heat (energy) Change, = H3-H1. This will normally be zero if:
1. There is no energy loss to/gained from the environment;
2. No reactions have Heat of Reaction (HoR) override;
If any of the above scenarios are true, then this value will not be zero.
TotalHeat.Error Overall heat (energy) error (imbalance). For steady-state projects, = H3 - (H1+H2). For dynamic projects, = (H3+H4) - (H1+H2).
TotalHeat.RelError Overall relative heat (energy) error.

Extended Audit Details

This table is only displayed if Audit.On and Basics.ShowExtra are ticked.

Tag (Long/Short) Description
Extended Audit Details
Details...
PowerIn (P1) Heat flow from External Heat Source.
PowerIn.RB (P2) Heat flow from External Heat Source in Reaction Block.
PowerIn.EHX (P3) Heat flow from External Heat Source in Environmental Heat Exchanger (EHX) sub-model.
PowerIn.T_Change (P4) Heat flow from External Heat Source used to control temperature in Makeup Blocks, Evaporation Block (Evap) or Split Thermal (SplitT) option.
PowerIn.Total Total heat flow from all sources, =P1+P2+P3+P4.
SensibleHeat.In (S1) Sensible Heat flowing in.
SensibleHeat.Out (S2) Sensible Heat flowing out.
SensibleHeat.Change Sensible Heat Change, S2-S1.
HOD.(Compound)@0.Nett Heat of Dilution due to compound @ 0°C and Reference pressure of 101.325kPa. This is for the change in concentration for the common flow between the input and output streams (ie minimum flowrate of inputs sum and outputs sum).

Basic Element Audit

This table is only displayed if ElemAudit.On is ticked.

Tag (Long/Short) Description
Basic Element Audit
ElBasics...
Mass.Error Overall mass error (imbalance), (mass of elements out) - (mass of elements in).
Mass.RelError Overall relative mass error.

Streams Audit Summary

This table is only displayed if Audit.On and Streams.Collect are ticked.

In the following table, next to each of the following fields there will be up to four columns. The columns are:

  1. Qm: The total mass flow in the current iteration/step.
  2. Mt: Total accumulated mass since the project was last restarted, only visible in a Dynamic project.
  3. Hf: The Total Enthalpy of all species in the current iteration/step.
  4. TotalHf: Total accumulated Enthalpy since the project was last restarted, only visible in a Dynamic project.
Tag (Long/Short) Description
Streams Audit Summary
Src (Source Material and Energy Entering Project)
Sources Material/energy which has been added:
- via a Reaction Block Source or Reaction Heat Exchange
- if the unit is a Feeder, then this is the amount of material/energy delivered by the Feeder. (Note, a Feeder is a true source of material to the project, unlike a cross page connector which moves material from one flowsheet to another.)
- if the unit is a Makeup Source, then this is the amount of material/energy delivered by the Makeup Source.
Also includes energy added via sub-models such as Environmental Heat Exchanger (EHX) block.
In (Links In)
PipesIn Material/energy which has entered the unit via a link (pipe).
Makeups Material/energy which has been added via a Makeup Block.
FromDiscards Material/energy which has been originated from a Discard Block. This is relevant for Discard Sink models.
Out (Links Out)
PipesOut Material/energy which has left the unit via a link (pipe).
ToMakeups Material/energy which has been sent to a Makeup Block. This is relevant for Makeup Source models.
Discards Material/energy which has been removed via a Discard Block.
Spills Material/energy which has been spilt. This is only visible in a dynamic project.
Vents Material/energy which has been vented. This is only visible in a dynamic project.
Snk (Sink Material and Energy Leaving Project)
Sinks Material/energy which has been removed:
- via a Reaction Block Sink
- if the unit is a Sink, then this is the amount of material/energy removed by the Sink. (Note, a Sink is a true sink of material from the project, unlike a cross page connector which moves material from one flowsheet to another.)
- if the unit is a Discard Sink, then this is the amount of material/energy removed by the Discard Sink.
Also includes energy removed via sub-models such as Environmental Heat Exchanger (EHX) block.
Audit------------
TotalIn The Total of all inputs = Sources + PipesIn + Makeups + FromDiscards
TotalOut The Total of all outputs = PipesOut + ToMakeups + Discards + Spills + Vents + Sinks
TotalNett TotalOut - TotalIn.
Accumulation This is only visible in a dynamic project. The net increase or decrease in material/energy due to change in content (surge).
Error The absolute error. For a steady state project, this will be the same as TotalNett. For a dynamic project this will be TotalOut + Accumulation - TotalIn.
RelError This is the relative error.

Elemental Audit

The following parameters and table are only displayed if Audit.On and Elements.Collect are ticked OR if ElemAudit.On is ticked. These will be shown on the AuditEl tab page.

Tag (Long/Short) Input / Calc Description
Zeros Show Zeros.png
Hide Zeros.png
Toggle between displaying all elements (even if ZERO flow) or only those with non-zero flow in the Audit Element Flows table below.
Options.Elements.ShowExtra Tickbox Only displayed if Audit.On and Elements.Collect are ticked. Show additional columns in the Audit Element Flows table below. Also shown on the Audit tab page.
Elements.DisplayTol.Rel Input Relative display tolerance for elemental mass imbalances. Also shown on the Audit tab page.
Audit Element Flows
ElFlows...
(The following table will contain one row for each element in the project. The columns shown for each element are described below:)
Src Display Only shown if the Options.Elements.ShowExtra option is ticked. Material which has been added via a reaction source, or if the unit is a Feeder then this is the amount of material delivered by the Feeder.
In Display Only shown if the Options.Elements.ShowExtra option is ticked. Material which has entered the unit.
Out Display Only shown if the Options.Elements.ShowExtra option is ticked. Material which has left the unit.
Snk Display Only shown if the Options.Elements.ShowExtra option is ticked. Material which has been removed via a reaction sink, or if the unit is a Sink then this is the amount of material removed via the Sink.
TotalIn Display Total material added to the unit.
TotalOut Display Total material leaving the unit.
AccumRate Display Only shown in a dynamic project. The change in material due to accumulation or depletion of content (surge).
Error Display The absolute elemental error. For a steady state project, this will be TotalOut - TotalIn. For a dynamic project this will be TotalOut + AccumRate - TotalIn.
RelError Display The relative elemental error.
(The following table is only visible in a dynamic project)
Audit Element Content
ElContent...
(The following table will contain one row for each element in the project. The columns shown for each element are described below:)
Accumulation Display The amount of material which has been accumulated in the content (surge) of the unit.
Depletion Display The amount of material which has been removed from the content (surge) of the unit.
(The following table is only shown if ElemAudit.On is ticked)
Basic Element Audit
ElBasics...
Mass.Error Display Overall mass error (imbalance), (mass of elements out) - (mass of elements in).
Mass.RelError Display Overall relative mass error.

Species Audit

The following parameters and table are only displayed if Audit.On and Species.Collect are ticked. These will be shown on the AuditSp tab page.

Tag (Long/Short) Input / Calc Description
SpeciesTag SpeciesLongButton.png
SpeciesShortButton.png
Toggle between displaying Species names as the chemical compound (short name), or the longer species names, in the Audit Species Flows table below. Refer to Species Long or Short Display Button for more information.
Note: This button is independent of the 'Tag:Long or Short' button that is used to toggle the field names on other pages of the Access window between the long and short forms.
Zeros Show Zeros.png
Hide Zeros.png
Toggle between displaying all species (even if ZERO flow) or only those with non-zero flow in the Audit Species Flows table below.
Options.Species.ShowExtra Tickbox Show additional columns in the Audit Species Flows table below. Also shown on the Audit tab page.
Audit Species Flows
SpFlows...
(The following table will contain one row for each species in the project. The columns shown for each species are described below:)
Src Display Only shown if the Options.Species.ShowExtra option is ticked. Material which has been added via a reaction source, or if the unit is a Feeder then this is the amount of material delivered by the Feeder.
In Display Only shown if the Options.Species.ShowExtra option is ticked. Material which has entered the unit.
Out Display Only shown if the Options.Species.ShowExtra option is ticked. Material which has left the unit.
Snk Display Only shown if the Options.Species.ShowExtra option is ticked. Material which has been removed via a reaction sink, or if the unit is a Sink then this is the amount of material removed via the Sink.
TotalIn Display Total material added to the unit.
TotalOut Display Total material leaving the unit.
TotalNett Display TotalOut - TotalIn.
AccumRate Display Only shown in a dynamic project. The change in material due to accumulation or depletion of content (surge).
(The following table is only visible in a dynamic project)
Audit Species Content
SpContent...
(The following table will contain one row for each species in the project. The columns shown for each species are described below:)
Accumulation Display The amount of material which has been accumulated in the content (surge) of the unit.
Depletion Display The amount of material which has been removed from the content (surge) of the unit.