ANSYS Contact Technology Guide

1 ANSYS ContactTechnology GuideANSYS Release 2004 ANSYS , Inc. is aUL registeredISO 9001: Contact Technology GuideANSYS Release , Technology DriveCanonsburg, PA 724-746-3304(F) 724-514-9494 Copyright and Trademark InformationCopyright 2004 SAS IP, Inc. All rights reserved. Unauthorized use, distribution or duplication is , DesignSpace, CFX, DesignModeler, DesignXplorer, ANSYS Workbench environment, AI*Environment, CADOE and any and all ANSYS , Inc. productnames referenced on any media, manual or the like, are registered trademarks or trademarks of subsidiaries of ANSYS , Inc. located in the United States orother countries. ICEM CFD is a trademark licensed by ANSYS , Inc. All other trademarks and registered trademarks are property of their respective , Inc. is a UL registered ISO 9001: 2000 Inc. products may contain Patent No. 6,055, , Windows, Windows 2000 and Windows XP are registered trademarks of Microsoft and Mechanical Desktop are registered trademarks of Autodesk, is a registered trademark of SolidWorks is a registered trademark of Parametric Technology , Solid Edge and Parasolid are registered trademarks of Electronic Data Systems Corporation (EDS).

2 ACIS and ACIS Geometric Modeler are registered trademarks of Spatial Technology , License Manager is a trademark of Macrovision ANSYS , Inc. software product and program documentation is ANSYS Confidential Information and are furnished by ANSYS , Inc. under an ANSYS software license agreement that contains provisions concerning non-disclosure, copying, length and nature of use, warranties, disclaimers and remedies,and other provisions. The Program and Documentation may be used or copied only in accordance with the terms of that license the ANSYS , Inc. online documentation or the ANSYS , Inc. documentation CD for the complete Legal this is a copy of a document published by and reproduced with the permission of ANSYS , Inc., it might not reflect the organization or physical appearanceof the original. ANSYS , Inc. is not liable for any errors or omissions introduced by the copying process. Such errors are the responsibility of the partyproviding the of Contents1. Contact Overview.

3 1 General Contact Classification .. 1 ANSYS Contact Capabilities .. 1 Surface-to-Surface Contact Elements .. 1 Node-to-Surface Contact Elements .. 1 Node-to-Node Contact Elements .. 1 32. GUI Aids for Contact Analyses .. 2 The Contact Manager .. 2 The Contact Wizard .. 2 Managing Contact Pairs .. 2 33. Surface-to-Surface Contact .. 3 Using Surface-to-Surface Contact Elements .. 3 Steps in a Contact Analysis .. 3 Creating the Model Geometry and Mesh .. 3 Identifying Contact Pairs .. 3 Designating Contact and Target Surfaces .. 3 Asymmetric Contact vs. Symmetric Contact .. 3 Background .. 3 Using KEYOPT(8) .. 3 Defining the Target Surface .. 3 Pilot Nodes .. 3 Primitives .. 3 Element Types and Real Constants .. 3 Defining Target Element Geometry .. 3 Using Direct Generation to Create Rigid Target Elements .. 3 Using ANSYS Meshing Tools to Create Rigid Target Elements .. 3 Some Modeling and Meshing Tips.

4 3 Verifying Nodal Number Ordering ( Contact Direction) of Target Surface .. 3 Defining the Deformable Contact Surface .. 3 Element Type .. 3 Real Constants and Material Properties .. 3 Generating Contact Elements .. 3 Set the Real Constants and Element KEYOPTS .. 3 Real Constants .. 3 Positive and Negative Real Constant Values .. 3 Element KEYOPTS .. 3 Selecting a Contact Algorithm (KEYOPT(2)) .. 3 Background .. 3 Determining Contact Stiffness and Allowable Penetration .. 3 Background .. 3 Using FKN and FTOLN .. 3 Using FKT and SLTO .. 3 Using KEYOPT(10) .. 3 Chattering Control Parameters .. 3 Choosing a Friction Model .. 3 Background .. 3 Using TAUMAX, FACT, DC, and COHE .. 3 Static and Dynamic Friction Coefficients .. 3 Selecting Location of Contact Detection .. 3 Background .. 3 25 ANSYS Contact Technology Guide . ANSYS Release . 002114 . SAS IP, Using KEYOPT(4) and TOLS .. 3 Adjusting Initial Contact Conditions.

5 3 Background .. 3 Using PMIN, PMAX, CNOF, ICONT, KEYOPT(5), and KEYOPT(9) .. 3 Physically Moving Contact Nodes Towards the Target Surface .. 3 Determining Contact Status and the Pinball Region .. 3 Background .. 3 Using PINB .. 3 Avoiding Spurious Contact in Self Contact Problems .. 3 Selecting Surface Interaction Models .. 3 Background .. 3 Using KEYOPT(12) and FKOP .. 3 Bonded Contact for Shell-Shell Assemblies .. 3 Modeling Contact with Superelements .. 3 Background .. 3 Using KEYOPT(3) .. 3 Accounting for Thickness Effect .. 3 Background .. 3 Using KEYOPT(11) .. 3 Using Time Step Control .. 3 Background .. 3 Using KEYOPT(7) .. 3 Using the Birth and Death Option .. 3 Controlling the Motion of the Rigid Target Surface (Rigid-to-Flexible Contact ) .. 3 Applying Necessary Boundary Conditions to the Deformable Elements .. 3 Defining Solution and Load Step Options .. 3 Solving the Problem .. 3 Reviewing the Results.

6 3 Points to Remember .. 3 Reviewing Results in POST1 .. 3 Reviewing Results in POST26 .. 3 454. Node-to-Surface Contact .. 4 The Node-to-Surface Contact Element .. 4 Performing a Node-to-Surface Contact Analysis .. 4 CONTA175 KEYOPTS .. 4 KEYOPT(3) .. 4 KEYOPT(4) .. 4 CONTA175 Real Constants .. 4 Using CONTA175 for Multiphysics Contact .. 4 35. Multiphysics Contact .. 5 Modeling Thermal Contact .. 5 Thermal Contact Behavior vs. Contact Status .. 5 Free Thermal Surface .. 5 Temperature on Target Surface .. 5 Modeling Conduction .. 5 Using TCC .. 5 Using the Quasi Solver Option .. 5 Modeling Convection .. 5 Modeling Radiation .. 5 Background .. 5 Using SBCT and RDVF .. 5 Modeling Heat Generation Due to Friction .. 5 4 ANSYS Contact Technology GuideANSYS Contact Technology Guide . ANSYS Release . 002114 . SAS IP, Background .. 5 Using FHTG and FWGT .. 5 Modeling External Heat Flux .. 5 Modeling Electric Contact .

7 5 Modeling Surface Interaction .. 5 Background .. 5 Using ECC .. 5 Modeling Heat Generation Due to Electric Current .. 5 Modeling Magnetic Contact .. 5 Using MCC .. 5 Modeling Perfect Magnetic Contact .. 5 86. Node-to-Node Contact .. 6 Node-to-Node Contact Elements .. 6 Performing a Node-to-Node Contact Analysis .. 6 Creating Geometry and Meshing the Model .. 6 Generating Contact Elements .. 6 Generating Contact Elements Automatically at Coincident Nodes .. 6 Generating Contact Elements Automatically at Offset Nodes .. 6 Node Ordering .. 6 Defining the Contact Normal .. 6 Defining the Initial Interference or Gap .. 6 Selecting the Contact Algorithm .. 6 Applying Necessary Boundary Conditions .. 6 Defining the Solution Options .. 6 Solving the Problem .. 6 Reviewing the Results .. 6 77. Multipoint Constraints and Assemblies .. 7 Modeling Solid-Solid and Shell-Shell Assemblies .. 7 Modeling a Shell-Solid Assembly.

8 7 Surface-Based Constraints .. 7 Defining Surface-Based Constraints .. 7 Modeling a Beam-Solid Assembly .. 7 Restrictions and Recommendations for Internal MPC .. 7 118. Spot Welds .. 8 Defining a Spot Weld Set .. 8 Creating a Basic Spot Weld Set with SWGEN .. 8 The Components of a Spot Weld .. 8 Adding Surfaces to a Basic Set .. 8 Listing and Deleting Spot Welds .. 8 11 List of Contact Manager Toolbar .. 2 Example of a Contact Wizard Dialog .. 2 Localized Contact Zones .. 3 ANSYS Geometric Entities and Their Corresponding Rigid Target Elements .. 3 A Single Circular Target Segment Created From Arc Line Segments .. 3 Meshing Patterns for Arbitrary Target Surfaces .. 3 Smoothing Convex Corner .. 3 Correct Node Ordering .. 3 Contact Element Types .. 3 12viiANSYS Contact Technology Guide . ANSYS Release . 002114 . SAS IP, Contact Technology Specification of the Contact Surface's Outward Normal .. 3 Depth of the Underlying Element.

9 3 Sliding Contact Resistance .. 3 Friction Decay .. 3 Contact Detection Located at Gauss Point .. 3 Contact Detection Point Location at Nodal Point .. 3 Node Slippage Using Nodal Integration KEYOPT(4) = 1 or 2 .. 3 Contact Surface Adjustment With ICONT .. 3 Contact Surface Adjustment (PMIN, PMAX) .. 3 A Scenario in Which Initial Adjustment Will Fail .. 3 Ignoring Initial Penetration, KEYOPT(9) = 1 .. 3 Components of True Penetration .. 3 Ramping Initial Interference .. 3 Effect of Moving Contact Nodes .. 3 Auto Spurious Prevention .. 3 Penalty-Based Shell-Shell Assembly .. 3 Node-to-Surface Contact Elements .. 4 Target Temperature .. 5 Node-to-Node Contact Elements .. 6 Contact Between Two Concentric Pipes .. 6 Two Concentric Pipes, Normals Rotated Properly .. 6 Example of Overconstrained Contact Problem .. 6 Example of Shell-Solid Assembly .. 7 Shell-Solid Assembly (Original Mesh) .. 7 Shell-Solid Assembly with Solid-Solid Constraint Option.

10 7 Shell-Solid Assembly with Shell-Shell Constraint Option .. 7 Shell-Solid Assembly with Shell-Solid Constraint Option .. 7 Shell-Solid Constraint, All Directions (KEYOPT(5) = 4) .. 7 Rigid Constraint Surface .. 7 Force-Distributed Surface .. 7 Beam-Solid Assembly Defined by Rigid Constraint Surface .. 7 Beam-Solid Assembly Defined by Force-distributed Surface .. 7 Example Spot Weld Configuration .. 8 Default Projection Direction for Node 1 .. 8 Default Projection Direction for Nodes 1 and 2 .. 8 User-specified Projection Direction, Node 1 .. 8 User-specified Projection Direction, Nodes 1 and 2 .. 8 Search Radius for Spot Weld .. 8 Nodes Included in Constraint Equations .. 8 Beam Element Created for Spot Weld .. 8 Surfaces Added to Basic Spot Weld Set .. 8 Node Reordering for Beam Elements .. 8 10 List of ANSYS Contact Capabilities .. 1 Summary of Real Constant Defaults in Different Environments .. 3 Summary of KEYOPT Defaults in Different Environments.