Aspen PlusSTEADYSTATESIMULATION10MAureinUserGuideAspenTechVOLUME 2
User Guide Volume 2 S T E A D Y S T A T E S I M U L A T I O N 10 AspenTech7 Version User Guide V O L U M E 2 Aspen Plus 7
COPYRIGHT1981—1999Aspen Technology,Inc.ALLRIGHTSRESERVEDTheflowsheet graphics and plot components of Aspen Plus were developed by MY-Tech, Inc.Aspen Aerotran", Aspen Pinch", ADVENT, Aspen B-JAc", Aspen Custom Modeler", AspenDynamics",Aspen Hetran",Aspen Plus,AspenTech,B-JAc,BioProcess Simulator (BPS)?DynaPlus,ModelManager,Plantelligence,thePlantelligencelogo,PolymersPlus,PropertiesPlus,SPEEDUP,andtheaspen leaflogoareeitherregisteredtrademarks,ortrademarks ofAspenTechnology, Inc.,in the United States and/or other countries.BATCHFRAC"andRATEFRAcaretrademarksofKochEngineeringCompany,Inc.Activator is a trademark of Software Security, Inc.RainbowSentinelSuperPro"isatrademarkofRainbowTechnologies,Inc.Elan License Manager isa trademark of Elan ComputerGroup,Inc.,Mountain View,California,USA.Microsoft Windows, Windows NT, Windows 95 and Windows 98 are either registered trademarks ortrademarks of Microsoft Corporation in the United States and/or other countries.All other brand and product names are trademarks or registered trademarks of their respectivecompanies.The License Manager portion of this product is based on:ElanLicenseManager1989-1997ElanComputerGroup,IncAll rights reservedUse of Aspen Plus and This ManualThis manual is intended as a guide to using Aspen Plus process modeling software. This documentation containsAspenTechproprietaryandconfidential informationandmaynotbedisclosed,used,orcopiedwithoutthepriorconsent of AspenTech or as setforth in the applicable license agreement.Users are solely responsible for theproper use of Aspen Plus and the application of the results obtained.AlthoughAspenTechhastestedthesoftwareandreviewedthedocumentation,thesolewarrantyforAspenPlusmaybefoundintheapplicablelicenseagreementbetweenAspenTechandtheuser.ASPENTECHMAKESNOWARRANTYORREPRESENTATION,EITHEREXPRESSORIMPLIED,WITHRESPECTTOTHISDOCUMENTATION,ITS QUALITY,PERFORMANCE,MERCHANTABILITY,ORFITNESSFORAPARTICULARPURPOSE
COPYRIGHT 1981—1999 Aspen Technology, Inc. ALL RIGHTS RESERVED The flowsheet graphics and plot components of Aspen Plus were developed by MY-Tech, Inc. Aspen Aerotran, Aspen Pinch, ADVENT® , Aspen B-JAC, Aspen Custom Modeler, Aspen Dynamics, Aspen Hetran, Aspen Plus® , AspenTech® , B-JAC® , BioProcess Simulator (BPS), DynaPlus, ModelManager, Plantelligence, the Plantelligence logo, Polymers Plus® , Properties Plus® , SPEEDUP® , and the aspen leaf logo are either registered trademarks, or trademarks of Aspen Technology, Inc., in the United States and/or other countries. BATCHFRAC and RATEFRAC are trademarks of Koch Engineering Company, Inc. Activator is a trademark of Software Security, Inc. Rainbow SentinelSuperPro is a trademark of Rainbow Technologies, Inc. Élan License Manager is a trademark of Élan Computer Group, Inc., Mountain View, California, USA. Microsoft Windows, Windows NT, Windows 95 and Windows 98 are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. All other brand and product names are trademarks or registered trademarks of their respective companies. The License Manager portion of this product is based on: Élan License Manager © 1989-1997 Élan Computer Group, Inc. All rights reserved Use of Aspen Plus and This Manual This manual is intended as a guide to using Aspen Plus process modeling software. This documentation contains AspenTech proprietary and confidential information and may not be disclosed, used, or copied without the prior consent of AspenTech or as set forth in the applicable license agreement. Users are solely responsible for the proper use of Aspen Plus and the application of the results obtained. Although AspenTech has tested the software and reviewed the documentation, the sole warranty for Aspen Plus may be found in the applicable license agreement between AspenTech and the user. ASPENTECH MAKES NO WARRANTY OR REPRESENTATION, EITHER EXPRESS OR IMPLIED, WITH RESPECT TO THIS DOCUMENTATION, ITS QUALITY, PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE
ContentsAbout This ManualFor More Information.ii.17-1Chapter17ConvergenceFlowsheet Recycles andDesign Specifications.17-1..17-2Convergence Options.....17-3SpecifyingTear ConvergenceParameters...17-4Specifying Default Methods.....17-5SpecifyingSequencingParameters.17-6Specifying Convergence Method Parameters....17-6Specifying Tear Streams ....17-7Initial EstimatesforTearStreams.Specifying User-Defined Convergence Blocks....17-8.17-8Convergence Methods.....17-9WEGSTEIN Method...DIRECT Method..17-11Secant Method....17-11.17-12BROYDENMethod.17-14NEWTONMethod...17-15COMPLEX Method..SQP Method.....17-1517-16Specifying Convergence Order...17-17Specifying the Calculation Sequence.Using Initial Guesses ...17-18Flowsheet Sequencing....17-1917-20ObtainingFinalConvergenceSequence17-20AddingSpecialOptionstotheSequence.17-20Viewing theSequence.CheckingConvergenceResults.17-2317-24ControlPanel Messages..17-26StrategiesforFlowsheetConvergence.17-26Tear Convergence Suggestions..17-28Design SpecificationConvergenceSuggestions.17-29FortranBlockConvergenceSuggestions.Resolving Sequence and Convergence Problems...17-30.17-34References.Chapler18Accessing Flowsheet Variables18-1AccessingFlowsheetVariables...18-1.18-2Types of Accessed Flowsheet Variables...Aspen Plus User GuideContents-iiiVersion 10.1-0
Aspen Plus User Guide Contents-iii Version 10.1-0 Contents About This Manual .i For More Information.ii Chapter 17 Convergence.17-1 Flowsheet Recycles and Design Specifications .17-1 Convergence Options.17-2 Specifying Tear Convergence Parameters.17-3 Specifying Default Methods.17-4 Specifying Sequencing Parameters.17-5 Specifying Convergence Method Parameters.17-6 Specifying Tear Streams .17-6 Initial Estimates for Tear Streams .17-7 Specifying User-Defined Convergence Blocks .17-8 Convergence Methods.17-8 WEGSTEIN Method.17-9 DIRECT Method.17-11 Secant Method.17-11 BROYDEN Method .17-12 NEWTON Method.17-14 COMPLEX Method.17-15 SQP Method.17-15 Specifying Convergence Order.17-16 Specifying the Calculation Sequence.17-17 Using Initial Guesses .17-18 Flowsheet Sequencing .17-19 Obtaining Final Convergence Sequence.17-20 Adding Special Options to the Sequence .17-20 Viewing the Sequence .17-20 Checking Convergence Results.17-23 Control Panel Messages .17-24 Strategies for Flowsheet Convergence .17-26 Tear Convergence Suggestions.17-26 Design Specification Convergence Suggestions .17-28 Fortran Block Convergence Suggestions .17-29 Resolving Sequence and Convergence Problems .17-30 References .17-34 Chapter 18 Accessing Flowsheet Variables .18-1 Accessing Flowsheet Variables .18-1 Types of Accessed Flowsheet Variables.18-2
Variable Definition Dialog Box..18-418-7ChoosingInput orResultsVariables.Guidelines for Choosing Input or Results Variables.18-7Using Parameter Variables..18-818-11AccessingVectors...18-12AccessingStreamandSubstreamVectors...18-12SubstreamMIXEDandStreamClassCONVENSubstream CISOLID..18-14Substream NC...18-15Component Attributes andPSD..18-1718-17AccessingBlockVectorsVariables Dependent on Stage Number or Segment Number..18-1818-20VariablesDependentonSectionNumberVariablesDependentonOperationStepNumber.18-20Variables Dependent on Component Number.18-20VariablesDependent on Component Numberand Stage or SegmentNumber......18-21VariablesDependent on StageNumberand SectionNumber.....18-23VariablesDependentonStageNumberandOperationStepNumber18-24VariablesDependent on Component Number,StageNumber,andStripper Number......18-24VariablesDependentonComponentNumber,StageNumber,and....18-25Operation StepNumber..Variables Dependent on Component Number, Accumulator Number,18-26andOperationStepNumber18-27MHeatX Profiles..18-27ReactorProfilesAccessingPropertyParameterVectors...18-28.19-1hapler 19Fortran Blocks and In-Line Fortran.Using Fortran in Aspen Plus...19-1.19-2About Fortran Blocks.....19-3Creating a Fortran Block......19-3IdentifyingFlowsheetVariables.....19-4EnteringFortranStatementsandDeclarations...19-5SpecifyingWhenFortranStatementsAreExecuted..19-5ConvergingLoopsIntroduced byFortranBlocks..19-14RulesforIn-LineFortran Statements....19-15Disabling Syntax Checking....19-16Writing tothe Screen andAspenPlusFiles....19-17InteractiveReadStatements.19-19RetainingVariablesBetweenIterationsandBlocks..19-19About the Interpreter..19-21AboutExternalFortran Subroutines....20-1Chapter20Sensitivity..20-1About Sensitivity Analysis...20-2DefiningaSensitivityBlockAspen Plus User GuideContents-ivVersion 10.1-0
Contents-iv Aspen Plus User Guide Version 10.1-0 Variable Definition Dialog Box.18-4 Choosing Input or Results Variables.18-7 Guidelines for Choosing Input or Results Variables .18-7 Using Parameter Variables.18-8 Accessing Vectors.18-11 Accessing Stream and Substream Vectors.18-12 Substream MIXED and Stream Class CONVEN.18-12 Substream CISOLID.18-14 Substream NC .18-15 Component Attributes and PSD.18-17 Accessing Block Vectors 18-17 Variables Dependent on Stage Number or Segment Number .18-18 Variables Dependent on Section Number .18-20 Variables Dependent on Operation Step Number .18-20 Variables Dependent on Component Number .18-20 Variables Dependent on Component Number and Stage or Segment Number.18-21 Variables Dependent on Stage Number and Section Number.18-23 Variables Dependent on Stage Number and Operation Step Number 18-24 Variables Dependent on Component Number, Stage Number, and Stripper Number.18-24 Variables Dependent on Component Number, Stage Number, and Operation Step Number .18-25 Variables Dependent on Component Number, Accumulator Number, and Operation Step Number .18-26 MHeatX Profiles.18-27 Reactor Profiles .18-27 Accessing Property Parameter Vectors.18-28 Chapter 19 Fortran Blocks and In-Line Fortran.19-1 Using Fortran in Aspen Plus .19-1 About Fortran Blocks .19-2 Creating a Fortran Block.19-3 Identifying Flowsheet Variables .19-3 Entering Fortran Statements and Declarations .19-4 Specifying When Fortran Statements Are Executed.19-5 Converging Loops Introduced by Fortran Blocks.19-5 Rules for In-Line Fortran Statements.19-14 Disabling Syntax Checking.19-15 Writing to the Screen and Aspen Plus Files .19-16 Interactive Read Statements .19-17 Retaining Variables Between Iterations and Blocks.19-19 About the Interpreter.19-19 About External Fortran Subroutines .19-21 Chapter 20 Sensitivity.20-1 About Sensitivity Analysis.20-1 Defining a Sensitivity Block .20-2
.20-2Creating a Sensitivity Block..20-3IdentifyingtheSampledFlowsheetVariables.20-4IdentifyingManipulatedFlowsheetVariables.Defining Tabulated Variables ....20-4.20-5ReinitializingBlocksandStreams.20-6EnteringOptionalFortranStatements.20-6Fortran Declarations.Chapter21DesignSpecifications:Feedback Control.21-1..21-1AboutDesignSpecifications...21-2Defining a Design Specification..21-3CreatingaDesign Specification..21-3IdentifyingSampledFlowsheetVariables...21-4Entering the Design Specification....21-5Identifying theManipulated Variable....21-5EnteringOptionalFortranStatementsUsing the Fortran Sheet.21-6.21-6Troubleshooting Design SpecificationsChapler22Optimization22-1.22-1AboutOptimization.22-2ConvergenceofOptimizationProblems..22-2RecommendedProcedureforOptimization.22-3Defining an Optimization Problem.22-3Creating an Optimization Problem.22-3IdentifyingSampledFlowsheetVariables.22-4EnteringtheObjectiveFunction.22-5IdentifyingtheManipulatedVariable.22-6About Constraints....22-6Defining Constraints....22-6Creating Constraints....22-6Identifying Sampled Flowsheet Variables for Constraints.22-7Specifying the Constraint Expression...22-8EnteringOptionalFortranStatements...22-9Using the Fortran Sheet..22-9Fortran Declarations.22-10ConvergenceofOptimizationProblems...22-10COMPLEX Method....22-10Sequential Quadratic Programming (SQP) Method.22-11TroubleshootingOptimizationProblems.23-1Chapter23Fitting a Simulation Model to Data..23-1Types of Data-Fit Applications...23-2Defining a Data-Fit Problem..23-3CreatingPoint-Data Data Sets..23-3IdentifyingFlowsheetVariables.23-5Entering the Measured Point-Data.Aspen Plus User GuideContents-vVersion 10.1-0
Aspen Plus User Guide Contents-v Version 10.1-0 Creating a Sensitivity Block.20-2 Identifying the Sampled Flowsheet Variables .20-3 Identifying Manipulated Flowsheet Variables.20-4 Defining Tabulated Variables .20-4 Reinitializing Blocks and Streams.20-5 Entering Optional Fortran Statements .20-6 Fortran Declarations .20-6 Chapter 21 Design Specifications: Feedback Control .21-1 About Design Specifications.21-1 Defining a Design Specification.21-2 Creating a Design Specification .21-3 Identifying Sampled Flowsheet Variables.21-3 Entering the Design Specification.21-4 Identifying the Manipulated Variable .21-5 Entering Optional Fortran Statements .21-5 Using the Fortran Sheet .21-6 Troubleshooting Design Specifications.21-6 Chapter 22 Optimization.22-1 About Optimization .22-1 Convergence of Optimization Problems.22-2 Recommended Procedure for Optimization .22-2 Defining an Optimization Problem.22-3 Creating an Optimization Problem.22-3 Identifying Sampled Flowsheet Variables.22-3 Entering the Objective Function.22-4 Identifying the Manipulated Variable .22-5 About Constraints.22-6 Defining Constraints.22-6 Creating Constraints.22-6 Identifying Sampled Flowsheet Variables for Constraints .22-6 Specifying the Constraint Expression.22-7 Entering Optional Fortran Statements.22-8 Using the Fortran Sheet .22-9 Fortran Declarations .22-9 Convergence of Optimization Problems .22-10 COMPLEX Method.22-10 Sequential Quadratic Programming (SQP) Method .22-10 Troubleshooting Optimization Problems.22-11 Chapter 23 Fitting a Simulation Model to Data .23-1 Types of Data-Fit Applications .23-1 Defining a Data-Fit Problem.23-2 Creating Point-Data Data Sets.23-3 Identifying Flowsheet Variables .23-3 Entering the Measured Point-Data.23-5