System Coupling User's Guide

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Introduction to the System Coupling User's Guide

System Coupling Overview

The Ansys Product Improvement Program

Coupled Analysis Licensing Requirements

System Coupling Capabilities

System Coupling Capabilities by Context
Participant Variables and Quantity Types Supported by System Coupling
Participant Support of System Coupling Capabilities

System Coupling Contexts: GUI, CLI, and Workbench

Steps of a System Coupling Analysis

System Coupling Analysis Types

Steady Analysis Type
Transient Analysis Type

System Coupling Settings

Units in System Coupling

Unit Conversions

Unit Syntax

Unit Multipliers

Commonly Used SI Units

SI Base Units
SI Data Transfer Quantity Units
SI Derived Units

Commonly Used Non-SI Units

Stops and Restarts of System Coupling Analyses

Stopping a Coupled Analysis
Restarting a Coupled Analysis

Migrating to Ansys System Coupling 2024 R2

Migrating Across Multiple Releases

Migrating Command-Line System Coupling Scripts

Changes to the Data Model
Changes to Commands

Known Issues and Limitations

Parallel Processing
Units
Graphical User Interface
Participants
Data Model
Postprocessing in EnSight

Using System Coupling's User Interfaces

Overview of System Coupling's User Interfaces

Supported Coupling Participants

Coupling Interfaces and Data Transfers

Rules for Adding Coupling Interfaces
Rules for Adding Data Transfers

Steps of a Coupled Analysis

Expressions in System Coupling

Expressions Validation

Expression Values

Expression Definitions

Variables in Expressions

Mathematical Operators, Constants, and Functions

Conditional and Boolean/Logical Statements

Units in Expressions

Python Expression Functions

Expression Function Definition, Validation, and Evaluation
Defining an Expression Function
Adding an Expression Function
Reloading Expression Function Modules

Named Expressions

Using Expressions to Set Data Model Values

Creating an Expression for an Immutable Single Value

Identifying Valid Expression Variables for Mutable Values

Creating an Expression for a Mutable Time Step Size

Creating an Expression for a Data Transfer Source Variable

Creating an Expression for a Data Transfer Source Variable in the GUI
Creating an Expression for a Data Transfer Source Variable in the CLI

Participant Solution Sequencing

Working with System Coupling's Data Model

Data Model Structure

Root-Level Containers

Viewing Data Model Contents

Viewing a Container's Contents
Viewing an Object's Children
Viewing the Contents of an Object's Children

Using System Coupling's Graphical User Interface (GUI)

Starting the System Coupling GUI

Starting the GUI from the Start Menu
Starting the GUI from the Command Line

System Coupling GUI Components

System Coupling GUI Messages and Icons

System Coupling GUI Menus

Menu-Bar Menus
Context Menus

Using the System Coupling Command-Line Interface (CLI)

Starting the System Coupling CLI
Getting Help in the System Coupling CLI

Preparing for a Coupled Analysis

Setting Up a Coupled Analysis Directory Structure
Completing Participant Setups
Additional Participant Setup Considerations
Generating Participant Files

Creating a Coupled Analysis

Adding the Participants

Adding a Coupling Interface

Adding a Data Transfer

Adding a Single Data Transfer
Adding a Data Transfer Group in the GUI

Modifying Coupled Analysis Settings

Changing Data Model Settings

Changing Data Model Values in the GUI
Changing Data Model Values in the CLI

Frequently Edited Data Model Settings

Running a Coupled Analysis

Starting the Solution
Monitoring Solution Progress

Common Coupled Analysis Tasks

Saving a Coupled Analysis

Working with Coupled Analysis Snapshots

Creation of Snapshots
Saving a Snapshot
Overwriting an Existing Snapshot
Printing a List of Available Snapshots
Opening a Snapshot
Deleting a Snapshot

Opening a New Working Directory from the GUI

Reconnecting the GUI to a Running Coupled Solution

Prerequisites
Disconnecting from the Running Solution
Reconnecting to the Running Solution

Stopping a Coupled Analysis

Restarting a Coupled Analysis

Creation of Restart Points
Restarting a Coupled Analysis in the GUI
Restarting a Coupled Analysis in the CLI

Advanced Coupled Analysis Tasks

Defining Geometry Transformations for Models with Different Orientations

Adding Reference Frames

Adding Transformations

Using Automatic Interface Alignment

Chaining Transformations

Chaining Manual-Automatic-Manual Transformations in the GUI

Chaining Manual-Automatic-Manual Transformations in the CLI

Defining Transformations for a Coupling Interface Side

Defining Interface Instancing for Cylindrical Geometry Models

Adding Instancing Objects
Defining Instancing for a Coupling Interface Side

Setting a Participant Connection Timeout Interval

Using Interactive Solve Commands

Simultaneous Execution of Participant Solutions

System Coupling's Participant Grouping Process
Enabling Simultaneous Participant Solutions
Execution of Simultaneous Participant Solutions
Simultaneous Participant Solution Examples

Using Parallel Processing Capabilities

Recommended Workflow for Parallel Execution

Parallel Processing for Coupling Participants

Machine List and Core Counts

Resource Allocation Fractions

Partitioning Algorithms

Choosing a Partitioning Algorithm

Partitioning Algorithm Pros and Cons

Participant Partitioning Examples

Shared Parallel: Allocate Machines
Shared Parallel: Allocate Cores
Distributed Parallel: Allocate Cores
Distributed Parallel: Allocate Machines
Custom Partitioning Examples

Applying Partitioning to Coupling Participants

Applying Participant Partitioning in the GUI
Applying Participant Partitioning in the CLI
Applying Custom Participant Partitioning

Parallel Options for System Coupling

Parallel Options for Participant Products

Adding Solver-Specific Parallel Arguments

Using AEDT HPC Distribution Options

Using Automatic HPC Distribution Options
Using Manual HPC Distribution Options

Running an Exported System Coupling Setup

Running an Exported Partial Setup
Running an Exported Full Setup

Requesting Debugging and Diagnostic Output

Reviewing Coupled Analysis Output and Results

Reviewing Convergence Diagnostics Charting Output

Core Charting Functionality
Chart Tab Context Menu
Viewing the Convergence Diagnostics Chart
Viewing Data Transfer Quantity Diagnostic Charts
Writing Charting Diagnostics to CSV Files

Postprocessing Coupling Results in EnSight

Types of EnSight Postprocessing Files

Postprocessing with EnSight Gold Results

Changing Settings for Auto-Generating EnSight Gold Results

Generating EnSight Gold Results on Demand

EnSight Gold Postprocessing for Restarts

Loading EnSight Gold Results into EnSight

Loading EnSight Gold Results from the GUI
Loading EnSight Gold Results from the CLI
Loading EnSight Gold Results with EnSight Startup
Opening EnSight Gold Results in an Existing Instance of EnSight

Reviewing Results in EnSight

Parts
Geometry Transformations and Instancing in EnSight Results
Variables
Graphics Window

Postprocessing with EnSight Live Visualization Results

Adding a Live Visualization Object
Enabling Live Visualization
Enabling Live Visualization Results Caching
Running a Co-Simulation with Live Visualization
Activating the EnSight DVS Reader
Loading Live Postprocessing Results into EnSight

Setting Up the EnSight Interface

Setting Up the Graphics Window
Setting Up the Viewports
Turning Off the Continuous Palette Setting

Working with Variables in EnSight

Variable Naming Conventions

Selecting Variables

Using Mapping Variables

Mapping Type Applicability
Mapping Variable Display

Visualizing Variable Data

Adjusting Plot Palette Ranges

EnSight Quick Reference

Adding a Text Annotation
Running a Simple Animation of Solution Time Steps
Adding a Simple Coordinate Probe
Adding a Time Annotation
Plotting Nodal Displacement as a Function of Time
Adding Force Vector Arrows

Using System Coupling in Workbench

Overview of System Coupling in Workbench

Supported Coupling Participants for System Coupling in Workbench
Data Transfers for System Coupling in Workbench
Steps of a Coupled Analysis in Workbench
System Coupling Tab in Workbench

Setting Up a Coupled Analysis in Workbench

Creating a Coupled Analysis

Completing Participant Setups

Connecting Systems on the Project Schematic

Completing the Coupling Setup

Setup Node Context Options

Coupling-Specific Properties

Analysis Settings

Analysis Type
Initialization Controls
Duration Controls
Step Controls

Participants

Regions

Data Transfers

Source/Target
Data Transfer Control
Data Transfer Context Options

Execution Control

Coupling Engine
Expert Settings
Intermediate Restart Data Output

Running a Coupled Analysis in Workbench

Starting the Solution

Monitoring Solution Progress

Viewing Transcript Output

Viewing System Coupling Charts

Availability of Chartable Data

Chart Properties

Chart Variables

Adding a Chart Variable
Chart Variable Properties

Chart Context Options

Chart Monitor Controls

Saving a Chart as a Graphic

Solution Validation and State

Solution Node Context Options

Common Tasks for System Coupling in Workbench

Stopping a System Coupling Analysis in Workbench

Restarting a Coupled Analysis in Workbench

Generating Restart Files in Workbench
Restarting a Coupled Analysis in Workbench
Recovering from a Workbench Crash

Advanced Tasks for System Coupling in Workbench

Requesting Debugging and Diagnostic Output

Requesting Debug Log Files

Exporting a System Coupling Setup

Steps to Create the System Coupling Setup
Files Needed for a User-Interface Run
Exporting Partial vs. Full Coupling Setups
Exporting the System Coupling Setup

Generating Participant Solver Input and Coupling Setup Files On Demand

Coupled Analysis Management

Inter-Process Communication
Convergence Management
Evaluating Convergence of Data Transfers

System Coupling Data Transfers

Rules for the Creation of Data Transfers

System Coupling's Data Transfer Process

System Coupling's Mapping Capabilities

Mapping Types

Mapping Topologies

Region Discretization Types

Mapping Process

Associating Source and Target Locations

Binary Space Partitioning Algorithm

Generating Data for Target Locations

Generating Data on Overlapping Locations

Generating Data on Non-Overlapping Locations

Mapping Algorithms by Mapping Type, Topology, and Region Discretization Type

Profile-Preserving Mapping Algorithms

Shape Functions
Radial Basis Functions
Element-Weighted Averages

Conservative Mapping Algorithms

Intersection Algorithm for Surface-to-Surface and Volume-to-Volume Mapping
Intersection Algorithm for Surface-to-Volume and Volume-to-Surface Mapping

Supplemental Processing Algorithms

Data Reconstruction Algorithms

Ramping Algorithm

Under-Relaxation Algorithm

Quasi-Newton Stabilization Algorithm

Using Quasi-Newton Stabilization

Changing Stabilization Settings in the GUI
Changing Stabilization Settings in the CLI
Enabling Stabilization for System Coupling in Workbench

Available Stabilization Settings

Quasi-Newton Recommendations

Quasi-Newton Limitations

System Coupling Input and Output Files

Files Used by System Coupling

Participant Setup File

<ExecutionControl>

<InitialInput>
<Command>

<CosimulationControl>

<Dimension>

<AnalysisType>

<DisplayName>

<RestartsSupported>

<Variables>

<Name>
<DisplayName>
<QuantityType>
<TensorType>
<IsExtensive>
<Location>

<Parameters>

<Parameter>

<Name>
<DisplayName>
<TensorType>

<InputParameters>

<Parameter>

<OutputParameters>

<Parameter>

<DisplayName>

<OutputVariables>

<Variable>

<InputVariables>

<Variable>

Sample System Coupling Participant File

<Transfers>
<ExecutionControl>
<Analysis>
<Participants>

Shutdown File

Files Generated by System Coupling

GUI Server File

Solution Lock File

Transcript and Log File

Summary of Coupling Setup

Library
Coupling Participants
Analysis Control
Coupling Interfaces
Solution Control
Output Control
One-Way Workflow Message
Pre-Solution Warnings and Messages
EnSight Output Display Name Modifications
Partitioning Information
Execution Information
Build Information

Analysis Initialization

Mesh Statistics
Mapping Summary
Reference Frame and Instancing Information
Transfer Diagnostics

Coupled Solution

Coupling Step

Mapping Summary
Coupling Iteration

Available Restart Points
Timing Summary

Settings File

Restart Files

Export Setup Log File

Ansys EnSight Results Files

Server File

Functional Mock-Up Unit (FMU) Co-Simulation Participants

Differences between FMU and Ansys Participants

Supported System Coupling Functionality

Co-Simulation with an FMU Participant

Adding an FMU Participant
Adding an FMU Proxy Participant
Adding Coupling Interfaces and Data Transfers

FMU CouplingParticipant Data Model Settings

Common Engineering Applications for System Coupling

Fluid-Structure Interaction (FSI)

Building a Coupled FSI Analysis from Decoupled Participant Problems

Step 1: Solve the Fluid and Structural Problems Independently
Step 2: Solve the Fluid and Structural Problems as One-Way Coupled Analyses
Step 3: Solve the Fluid and Structural Problems as a Two-Way Coupled Analysis

Choosing the Mesh-Related Timescale

Defining Mesh Motion and Deformation Settings

Aerodynamic Damping Analysis

Coupling Participants

Verify Coupling Participant Input Files

Add Coupling Participants

Define the Mechanical Server

Define the CFD Server

Set Execution Control Parameters
Define Participant Instancing

Coupling Interfaces

Add a Coupling Interface
Add Data Transfers
Using Expressions

Handling Participant Setup Changes

Performing Mapping

Verifying Mapping Results

Review the System Coupling Transcript
Visualize Mapped Results in EnSight

Improving Mapping Results

Performing Remapping

Using Mapping Results

Electric Arc Modeling

Coupling Participants

Setting Up Coupling Participants
Adding Coupling Participants

Coupling Interfaces

Adding a Coupling Interface
Adding Data Transfers

Solving the Analysis

Monitoring and Postprocessing

Best Practices for System Coupling

General Best Practices for Coupled Analyses

Building Up to a Coupled Analysis
Improving Mapping Quality
Evaluating Convergence and Data Transfer Accuracy
Improving the Accuracy of Steady Analyses
Improving the Accuracy of Transient Analyses

Improving Coupled Analysis Stability

Quasi-Newton Solution Stabilization
Data Transfer Ramping
Data Transfer Relaxation
Participant Solution Stabilization