ANSYS Structural Analysis Guide Table of Contents

ANSYS Structural Analysis GuideTable of Contents

Title, Disclaimer of Warranty and Liability

Preface

Topics in This Manual

Topics in Other ANSYS Manuals

Conventions This Manual Uses

The ANSYS Product Family

1 Overview of Structural Analyses

1.1 Definition of Structural Analysis

1.2 Types of Structural Analysis

1.3 Elements Used in Structural Analyses

1.4 Types of Solution Methods

2 Structural Static Analysis

2.1 Definition of Static Analysis

2.2 Loads in a Static Analysis

2.3 Linear vs. Nonlinear Static Analyses

2.4 Commands Used in a Static Analysis

2.5 Overview of Steps in a Static Analysis

2.5.1 Build the Model

2.5.1.1 Points to Remember

2.5.2 Apply Loads and Obtain the Solution

2.5.2.1 Enter the ANSYS Solution Processor

2.5.2.2 Define the Analysis Type and Options

2.5.2.3 Apply Loads to the Model

2.5.2.4 Load Types

ANSYS Structural Analysis Guide Table of Contents (UP19980818 ) http://uic.edu/depts/accc/software/ansys/html/guide_55/g-str/GSTRToc.htm

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2.5.2.5 Specify Load Step Options

2.5.2.6 General Options

2.5.2.7 Nonlinear Options

2.5.3 Review the Results

2.5.3.1 Postprocessors


2.5.3.3 Reviewing Results Data

2.5.3.4 Option: Display Deformed Shape

2.5.3.5 Option: List Reaction Forces and Moments

2.5.3.6 Option: List Nodal Forces and Moments

2.5.3.7 Option: Line Element Results

2.5.3.8 Option: Error Estimation

2.5.3.9 Option: Structural Energy Error Estimation

2.5.3.10 Option: Contour Displays

2.5.3.11 Option: Vector Displays

2.5.3.12 Option: Tabular Listings

2.5.3.13 Other Capabilities

2.6 A Sample Static Analysis (GUI Method)

2.6.1 Problem Description

2.6.2 Problem Specifications

2.6.3 Problem Sketch

2.6.3.1 Set the Analysis Title

2.6.3.2 Set the System of Units

2.6.3.3 Define Parameters

2.6.3.4 Define the Element Types

2.6.3.5 Define Material Properties

2.6.3.6 Create Hexagonal Area as Cross-Section

2.6.3.7 Create Keypoints Along a Path


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2.6.3.8 Create Lines Along a Path

2.6.3.9 Create Line from Shank to Handle

2.6.3.10 Cut Hex Section

2.6.3.11 Set Meshing Density

2.6.3.12 Set Element Type for Area Mesh

2.6.3.13 Generate Area Mesh

2.6.3.14 Drag the 2D Mesh to Produce 3D Elements

2.6.3.15 Select BOTAREA Component and Delete 2DElements

2.6.3.16 Apply Displacement Boundary Condition at End of Wrench

2.6.3.17 Display Boundary Conditions

2.6.3.18 Apply Pressure on Handle

2.6.3.19 Write the First Load Step

2.6.3.20 Define Downward Pressure

2.6.3.21 Write Second Load Step

2.6.3.22 Solve from Load Step Files

2.6.3.23 Read First Load Step and Review Results

2.6.3.24 Read the Next Load Step and Review Results

2.6.3.25 Zoom in on Cross-Section

2.6.3.26 Exit ANSYS

2.7 A Sample Static Analysis (Command or Batch Method)

2.8 Where to Find Other Examples

2.9 Calculating Inertia Relief

2.9.1 Inertia Relief

2.9.2 Inertia Relief Output

2.9.3 Partial Inertia Relief Calculations

2.9.4 Using a Macro

3 Modal Analysis


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3.1 Definition of Modal Analysis

3.2 Uses for Modal Analysis

3.3 Commands Used in a Modal Analysis

3.4 Overview of Steps in a Modal Analysis




3.4.2.1 Option: New Analysis [ANTYPE]

3.4.2.2 Option: Analysis Type: Modal [ANTYPE]

3.4.2.3 Option: Mode Extraction Method [MODOPT]

3.4.2.4 Option: Number of Modes to Extract [MODOPT]

3.4.2.5 Option: Number of Modes to Expand [MXPAND]

3.4.2.6 Option: Mass Matrix Formulation [LUMPM]

3.4.2.7 Option: Prestress Effects Calculation [PSTRES]

3.4.2.8 Additional Modal Analysis Options

3.4.2.9 Listing Loads

3.4.2.10 Damping (Dynamics Options)

3.4.2.11 Participation Factor Table Output

3.4.3 Expand the Modes


3.4.3.2 Expanding the Modes

3.4.3.3 Option: Expansion Pass On/Off [EXPASS]

3.4.3.4 Option: Number of Modes to Expand [MXPAND, NMODE]

3.4.3.5 Option: Frequency Range for Expansion [MXPAND, FREQB, FREQE]

3.4.3.6 Option: Stress Calculations On/Off [MXPAND,Elcalc]




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3.4.4.2 Reviewing Results Data

3.4.4.3 Option: Listing All Frequencies


3.4.4.5 Option: List Master DOF





3.5 A Sample Modal Analysis (GUI Method)




3.5.3.1 Specify the Title and Set Preferences

3.5.3.2 Define Element Types


3.5.3.4 Create Keypoints at Given Locations

3.5.3.5 Create Lines and Splines between Keypoints

3.5.3.6 Create Cross-Sectional Area

3.5.3.7 Define the Mesh Density and Mesh the Area

3.5.3.8 Set the Number of Line Divisions

3.5.3.9 Extrude the Meshed Area into a Meshed Volume

3.5.3.10 Enter Solution and Specify Analysis Type andOptions

3.5.3.11 Deselect PLANE42 Elements

3.5.3.12 Apply Constraints to the Model

3.5.3.13 Specify the Number of Modes to be Expanded and Solve

3.5.3.14 List the Natural Frequencies

3.5.3.15 View the Five Modes


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3.5.3.16 Exit ANSYS

3.6 A Sample Modal Analysis (Command or Batch Method)


3.8 Prestressed Modal Analysis

3.9 Prestressed Modal Analysis of a Large Deflection Solution

3.10 Modal Analysis of a Cyclically Symmetric Structure

3.10.1 The Basic Sector

3.10.2 Nodal Diameters

3.10.3 Standard (Stress-free) Modal Cyclic Symmetry

3.10.3.1 Overview

3.10.4 Prestressed Modal Cyclic Symmetry

3.11 Mode Extraction Methods

3.11.1 Subspace Method

3.11.2 Block Lanczos Method

3.11.3 PowerDynamics Method

3.11.4 Reduced Method

3.11.5 Unsymmetric Method

3.11.6 Damped Method

3.11.6.1 Damped Method-Real and Imaginary Parts of theEigenvalue

3.11.6.2 Damped Method-Real and Imaginary Parts of theEigenvector

3.12 Matrix Reduction

3.12.1 Theoretical Basis of Matrix Reduction

3.12.1.1 Guidelines for Selecting Master DOF

3.12.1.2 A Note About Program-Selected Masters

4 Harmonic Response Analysis

4.1 Definition of Harmonic Response Analysis

4.2 Uses for Harmonic Response Analysis


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4.3 Commands Used in a Harmonic Response Analysis

4.4 The Three Solution Methods

4.4.1 The Full Method

4.4.2 The Reduced Method

4.4.3 The Mode Superposition Method

4.4.4 Restrictions Common to All Three Methods

4.5 How to Do Harmonic Response Analysis

4.5.1 Full Harmonic Response Analysis





4.5.3.2 Option: Analysis Type: Harmonic Response[ANTYPE]

4.5.3.3 Option: Solution Method [HROPT]

4.5.3.4 Option: Solution Listing Format [HROUT]


4.5.3.6 Option: Equation Solver [EQSLV]



4.5.3.9 Dynamics Options

4.5.3.10 Output Controls






4.5.4.5 Option: Vector Plots


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4.6 Sample Harmonic Response Analysis (GUI Method)



4.6.3 Problem Diagram



4.6.3.3 Define the Real Constants

4.6.3.4 Create the Nodes

4.6.3.5 Create the Spring Elements

4.6.3.6 Create the Mass Elements

4.6.3.7 Specify the Analysis Type, MDOF, and Load StepSpecifications

4.6.3.8 Define Loads and Boundary Conditions

4.6.3.9 Solve the Model

4.6.3.10 Review the Results

4.6.3.11 Exit ANSYS

4.7 Sample Harmonic Response Analysis (Command or Batch Method)


4.9 Reduced Harmonic Response Analysis

4.9.1 Apply Loads and Obtain the Reduced Solution

4.9.2 Review the Results of the Reduced Solution

4.9.3 Expand the Solution (Expansion Pass)


4.9.3.2 Expanding the Modes


4.9.3.4 Option: Number of Solutions to Expand [NUMEXP,NUM]

4.9.3.5 Option: Frequency Range for Expansion [NUMEXP, BEGRNG, ENDRNG]


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4.9.3.6 Option: Phase Angle for Expansion [HREXP]

4.9.3.7 Option: Stress Calculations On/Off [NUMEXP or EXPSOL]

4.9.3.8 Option: Nodal Solution Listing Format [HROUT]

4.9.4 Review the Results of the Expanded Solution

4.9.5 Sample Input

4.9.6 Mode Superposition Harmonic Response Analysis

4.9.7 Obtain the Modal Solution

4.9.8 Obtain the Mode Superposition Harmonic Solution

4.9.9 Expand the Mode Superposition Solution


4.9.11 Sample Input

4.10 Other Analysis Details

4.10.1 Prestressed Harmonic Response Analysis

4.10.1.1 Prestressed Reduced Harmonic ResponseAnalysis

4.10.2 Prestressed Mode Superposition Harmonic ResponseAnalysis

5 Transient Dynamic Analysis

5.1 Definition of Transient Dynamic Analysis

5.2 Commands Used in a Transient Dynamic Analysis

5.3 Preparing for a Transient Dynamic Analysis

5.4 The Three Solution Methods

5.4.1 The Full Method

5.4.2 The Reduced Method

5.4.3 The Mode Superposition Method

5.5 How to Do a Transient Dynamic Analysis

5.5.1 Full Transient Dynamic Analysis




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5.5.3.2 Option: Analysis Type [ANTYPE]

5.5.3.3 Option: Solution Method [TRNOPT]


5.5.3.5 Option: Large Deformation Effects [NLGEOM]

5.5.3.6 Option: Stress Stiffening Effects [SSTIF]

5.5.3.7 Option: Newton-Raphson Option [NROPT]

5.5.3.8 Option: Equation Solver [EQSLV]

5.5.3.9 Applying Loads Using Commands

5.5.3.10 Applying Loads Using the GUI




5.5.3.14 Nonlinear Options

5.5.3.15 Output Control Options




5.5.4.3 Using POST26


5.5.4.5 Using POST1


5.5.4.7 Option: List Reaction Forces and Moments

5.5.4.8 Option: List Nodal Forces and Moments


5.5.4.10 Option: Print Error Estimation

5.5.4.11 Option: Display Contour of Error Estimation


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5.5.5 Sample Input

5.6 Reduced Transient Dynamic Analysis

5.6.1 Obtain the Reduced Solution




5.6.2 Step 3: Review the Results of the Reduced Solution

5.6.3 Expand the Solution (Expansion Pass)


5.6.3.2 Expanding the Solution


5.6.3.4 Option: Number of Solutions to be Expanded [NUMEXP]

5.6.3.5 Option: Single Solution to Expand [EXPSOL]

5.6.3.6 Output Controls

5.6.4 Review the Results of the Expanded Solution

5.7 Sample Transient Dynamic Analysis (GUI Method)




5.7.3.1 Specify the Title

5.7.3.2 Define Element Types

5.7.3.3 Define Real Constants


5.7.3.5 Define Nodes


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5.7.3.6 Define Elements

5.7.3.7 Define Analysis Type and Analysis Options

5.7.3.8 Define Master Degrees of Freedom

5.7.3.9 Set Load Step Options

5.7.3.10 Apply Loads for the First Load Step

5.7.3.11 Specify Output

5.7.3.12 Solve the First Load Step

5.7.3.13 Apply Loads for the Next Load Step

5.7.4 Solve the Next Load Step

5.7.4.1 Set the Next Time Step and Solve

5.7.4.2 Run the Expansion Pass and Solve

5.7.4.3 Review the Results in POST26

5.7.4.4 Review the Results in POST1

5.7.4.5 Exit ANSYS

5.8 A Sample Transient Dynamic Analysis (Command or Batch Method)


5.10 Mode Superposition Transient Dynamic Analysis


5.10.2 Obtain the Mode Superposition Transient Solution


5.10.2.2 Obtaining the Solution






5.10.3 Expand the Mode Superposition Solution



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5.10.5 Sample Input

5.11 Prestressed Transient Dynamic Analysis

5.11.1 Prestressed Full Transient Dynamic Analysis

5.11.2 Prestressed Reduced Transient Dynamic Analysis

5.11.3 Prestressed Mode Superposition Transient DynamicAnalysis

5.12 Other Analysis Details

5.12.1 Guidelines for Integration Time Step

5.12.2 Automatic Time Stepping

5.12.3 Damping

6 Spectrum Analysis

6.1 Definition of Spectrum Analysis

6.2 What is a Spectrum?

6.2.1 Response Spectrum

6.2.1.1 Single-point Response Spectrum (SPRS)

6.2.1.2 Multi-Point Response Spectrum (MPRS)

6.2.2 Dynamic Design Analysis Method (DDAM)

6.2.3 Power Spectral Density

6.2.4 Deterministic vs. Probabilistic Analyses

6.3 Commands Used in a Spectrum Analysis

6.4 Steps in a Single-point Response Spectrum (SPRS) Analysis




6.4.3 Obtain the Spectrum Solution


6.4.3.2 Option: Analysis Type: Spectrum [ANTYPE]

6.4.3.3 Option: Spectrum Type: Single-point ResponseSpectrum [SPOPT]


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6.4.3.4 Option: Number of Modes to Use for Solution[SPOPT]

6.4.3.5 Spectrum Options

6.4.4 Damping (Dynamics Options)


6.4.6 Combine the Modes









6.5 Sample Spectrum Analysis (GUI Method)




6.5.4 Procedure


6.5.4.2 Define the Element Type



6.5.4.5 Define Keypoints and Line

6.5.4.6 Set Global Element Density and Mesh Line

6.5.4.7 Set Boundary Conditions

6.5.4.8 Specify Analysis Type and Options

6.5.4.9 Solve the Modal Analysis


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6.5.4.10 Set Up the Spectrum Analysis

6.5.4.11 Define Spectrum Value vs. Frequency Table

6.5.4.12 Solve Spectrum Analysis

6.5.4.13 Set up the Expansion Pass

6.5.4.14 Expand the Modes

6.5.4.15 Start Expansion Pass Calculation

6.5.4.16 Set Up Mode Combination for Spectrum Analysis

6.5.4.17 Select Mode Combination Method

6.5.4.18 Combine the Modes

6.5.4.19 Postprocessing: Print Out Nodal, Element, andReaction Solutions

6.5.4.20 Exit ANSYS

6.6 Sample Spectrum Analysis (Command or Batch Method)


6.8 How to Do a Random Vibration (PSD) Analysis


6.8.2 Obtain the Spectrum Solution

6.8.3 Combine the Modes




6.8.4.1 Reviewing the Results in POST1

6.8.4.2 Calculating Response PSDs in POST26

6.8.4.3 Calculating Covariance in POST26

6.8.5 Sample Input

6.9 How to Do DDAM Spectrum Analysis

6.10 How to Do Multi-point Response Spectrum (MPRS) Analysis

7 Buckling Analysis


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7.1 Definition of Buckling Analysis

7.2 Types of Buckling Analyses

7.2.1 Nonlinear Buckling Analysis

7.2.2 Eigenvalue Buckling Analysis

7.3 Commands Used in a Buckling Analysis

7.4 Procedure for Nonlinear Buckling Analysis

7.4.1 Applying Load Increments

7.4.2 Automatic Time Stepping

7.4.3 Important

7.4.4 Points to Remember

7.5 Procedure for Eigenvalue Buckling Analysis



7.5.2 Obtain the Static Solution

7.5.3 Obtain the Eigenvalue Buckling Solution


7.5.3.2 Option: Analysis Type: Eigen Buckling [ANTYPE]

7.5.3.3 Option: Eigenvalue Extraction Method [BUCOPT]

7.5.3.4 Option: Number of Eigenvalues to be Extracted [BUCOPT]

7.5.3.5 Option: Shift Point for Eigenvalue Calculation [BUCOPT]

7.5.3.6 Option: Number of Reduced Eigenvectors to Print [BUCOPT]

7.5.4 Expand the Solution


7.5.4.2 Expanding the Solution

7.5.4.3 Option: Expansion Pass ON/OFF [EXPASS]

7.5.4.4 Option: Number of Modes to Expand [MXPAND]

7.5.4.5 Option: Stress Calculations On/Off [MXPAND]



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7.6 Sample Buckling Analysis (GUI Method)





7.6.3.2 Define the Element Type

7.6.3.3 Define the Real Constants and MaterialProperties

7.6.3.4 Define Nodes and Elements

7.6.3.5 Define the Boundary Conditions

7.6.3.6 Solve the Static Analysis

7.6.3.7 Solve the Buckling Analysis

7.6.3.8 Review the Results

7.6.3.9 Exit ANSYS

7.7 Sample Buckling Analysis (Command or Batch Method)


8 Nonlinear Structural Analysis

8.1 What is Structural Nonlinearity?

8.1.1 Causes of Nonlinear Behavior

8.1.1.1 Changing Status (Including Contact)

8.1.1.2 Geometric Nonlinearities

8.1.1.3 Material Nonlinearities

8.1.2 Basic Information About Nonlinear Analyses

8.1.2.1 Conservative versus Nonconservative Behavior;Path Dependency

8.1.2.2 Substeps

8.1.2.3 Load and Displacement Directions

8.1.2.4 Nonlinear Transient Analyses

8.2 Using Geometric Nonlinearities


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8.2.1 Stress Stiffening

8.2.2 Spin Softening

8.3 Modeling Material Nonlinearities

8.3.1 Nonlinear Materials

8.3.1.1 Plasticity

8.3.1.2 Multilinear Elasticity

8.3.1.3 Hyperelasticity

8.3.1.4 Determining and Applying Mooney-RivlinConstants

8.3.1.5 Dimension the Arrays

8.3.1.6 Fill the Input-Data Arrays

8.3.1.7 Determine the Mooney-Rivlin Constants

8.3.1.8 Evaluate the Quality of the Mooney-RivlinConstants

8.3.1.9 Using the Mooney-Rivlin Constants

8.3.1.10 Creep

8.3.1.11 Viscoplasticity

8.3.1.12 Viscoelasticity

8.3.1.13 Swelling

8.4 Running a Nonlinear Analysis in ANSYS



8.4.2.1 Advanced Analysis Options

8.4.2.2 Advanced Load Step Options



8.4.3.2 Reviewing Results in POST1




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8.4.4 Terminating a Running Job; Restarting

8.5 Sample Nonlinear Analysis (GUI Method)




8.5.3.1 Set the Analysis Title and Jobname



8.5.3.4 Define and Fill Kinematic Hardening table (KINH)

8.5.3.5 Label Graph Axes and Plot Data Tables

8.5.3.6 Create Rectangle

8.5.3.7 Set Element Size

8.5.3.8 Mesh the Rectangle

8.5.3.9 Assign Analysis and Load Step Options

8.5.3.10 Monitor the Displacement

8.5.3.11 Apply Constraints

8.5.3.12 Solve the First Load Step

8.5.3.13 Solve the Next Six Load Steps

8.5.3.14 Review the Monitor File

8.5.3.15 Use the General Postprocessor to Plot Results.

8.5.3.16 Define Variables for Time-History Postprocessing

8.5.3.17 Plot Time-History Results

8.5.3.18 Exit ANSYS

8.6 Sample Nonlinear Analysis (Command or Batch Method)


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8.8 Doing a Nonlinear Transient Analysis




8.9 Sample Input

8.10 Restarts

8.11 Using Nonlinear (Changing-Status) Elements

8.11.1 Element Birth and Death

8.12 Tips and Guidelines for Nonlinear Analysis

8.12.1 Starting Out with Nonlinear Analysis

8.12.1.1 Be Aware of How the Program and Your StructureBehave

8.12.1.2 Keep It Simple

8.12.1.3 Use an Adequate Mesh Density

8.12.1.4 Apply the Load Gradually

8.12.2 Overcoming Convergence Problems

8.12.2.1 Tracking Convergence Graphically

8.12.2.2 Using Automatic Time Stepping

8.12.2.3 Using Line Search

8.12.2.4 Using the Arc-Length Method

8.12.2.5 Artificially Inhibit Divergence in Your Model'sResponse

8.12.2.6 Turn Off Extra Element Shapes

8.12.2.7 Using Birth and Death Wisely

8.12.2.8 Read Your Output

8.12.2.9 Graph the Load and Response History

9 Contact

9.1 Contact Overview


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9.1.1 Explicit Dynamics Contact Capabilities

9.2 General Contact Classification

9.3 ANSYS Contact Capabilities

9.3.1 Surface-to-Surface Contact Elements

9.3.2 Node-to-Surface Contact Elements

9.3.3 Node-to-Node Contact Elements

9.4 Performing a Surface-to-Surface Contact Analysis

9.4.1 Using Surface-to-Surface Contact Elements

9.4.2 Steps in a Contact Analysis

9.4.3 Creating the Model Geometry and Mesh

9.4.4 Identifying Contact Pairs

9.4.5 Designating Contact and Target Surfaces

9.4.6 Asymmetric Contact vs. Symmetric Contact

9.4.7 Defining the Target Surface

9.4.7.1 Pilot Nodes

9.4.7.2 Primitives

9.4.7.3 Element Types and Real Constants

9.4.7.4 Using Direct Generation to Create Rigid TargetElements

9.4.7.5 Using ANSYS Meshing Tools to Create RigidTarget Elements

9.4.8 Defining the Deformable Contact Surface

9.4.8.1 Element Type

9.4.8.2 Real Constants and Material Properties

9.4.8.3 Generating Contact Elements

9.4.9 Set the Real Constants and Element Key Options

9.4.9.1 Real Constants

9.4.9.2 Element Key Options

9.4.9.3 Selecting a Contact Algorithm


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9.4.9.4 Determining Contact Stiffness

9.4.9.5 Choosing a Friction Model

9.4.9.6 Selecting Location of Contact Detection

9.4.9.7 Adjusting Initial Contact Conditions

9.4.9.8 Determining Contact Status and the PinballRegion

9.4.9.9 Avoiding Spurious Contact in Symmetric ContactProblems

9.4.9.10 Selecting Surface Interaction Models

9.4.9.11 Modeling Contact with Superelements

9.4.9.12 Accounting for Thickness Effect

9.4.9.13 Using Time Step Control

9.4.9.14 Using the Birth and Death Option

9.4.10 Controling the Motion of the Rigid Target Surface (Rigid-to-Flexible Contact Only)

9.4.11 Applying Necessary Boundary Conditions to the Deformable Elements

9.4.12 Defining Solution and Load Step Options

9.4.13 Solving the Problem

9.4.14 Reviewing the Results





9.4.14.5 Option: Animation




9.5 Performing a Node-to-Surface Contact Analysis

9.5.1 Using Node-to-Surface Contact Elements

9.5.2 Steps in a Node-to-Surface Contact Analysis


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9.5.2.1 Create the Geometry and Mesh

9.5.2.2 Identify the Contact Pairs

9.5.2.3 Generate the Contact Elements

9.5.2.4 Set the Element Key Options and Real Constants

9.5.2.5 Applying Necessary Boundary Conditions

9.5.2.6 Defining Solution Options

9.5.2.7 Solving the Problem

9.5.2.8 Reviewing the Results

9.5.2.9 Using CONTAC26

9.6 Performing a Node-to-Node Contact Analysis

10 Fracture Mechanics

10.1 Definition of Fracture Mechanics

10.2 Solving Fracture Mechanics Problems

10.2.1 Modeling the Crack Region

10.2.1.1 2-D Fracture Models

10.2.1.2 3-D Fracture Models

10.2.2 Calculating Fracture Parameters

10.2.2.1 Stress Intensity Factors

10.2.2.2 J-Integral

10.2.2.3 Energy Release Rate

11 Composites

11.1 Definition of Composites

11.2 Modeling Composites

11.2.1 Choosing the Proper Element Type

11.2.2 Defining the Layered Configuration

11.2.2.1 Specifying Individual Layer Properties

11.2.2.2 Defining the Constitutive Matrices

11.2.2.3 Sandwich and Multiple-Layered Structures


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11.2.2.4 Node Offset

11.2.3 Specifying Failure Criteria

11.2.4 Additional Modeling and Postprocessing Guidelines

12 Fatigue

12.1 Definition of Fatigue

12.1.1 What the ANSYS Program Does

12.1.2 Basic Terminology

12.2 Doing a Fatigue Evaluation

12.2.1 Enter POST1 and Resume Your Database

12.2.2 Establish the Size, Fatigue Material Properties, andLocations

12.2.3 Store Stresses and Assign Event Repetitions and ScaleFactors

12.2.3.1 Storing Stresses

12.2.3.2 Listing, Plotting, or Deleting Stored Stresses

12.2.3.3 Assigning Event Repetitions and Scale Factors

12.2.3.4 Guidelines for Obtaining Accurate Usage Factors

12.2.4 Activate the Fatigue Calculations


12.2.6 Other Approaches to Range Counting

12.2.7 Sample Input

13 p-Method Structural Static Analysis

13.1 Definition of p-Method Analysis

13.2 Benefits of Using the p-Method

13.3 Using the p-Method

13.3.1 Select the p-Method Procedure



13.3.2.2 Specify Material Properties and/or Real


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Constants

13.3.2.3 Define the Model Geometry

13.3.2.4 Mesh the Model into Solid or Shell Elements

13.3.3 Additional Information for Building Your Model

13.3.3.1 Viewing your element model

13.3.3.2 Coupling


13.3.5 Helpful Hints for Common Problems


13.3.6.1 The p-Element Subgrid

13.3.7 Querying Subgrid Results

13.3.8 Printing and Plotting Node and Element Results

13.3.8.1 Specialized p-Method Displays and Listings

13.4 Sample p-Method Analysis (GUI Method)



13.4.3 Problem Diagram


13.4.3.2 Select p-Method

13.4.3.3 Define the Element Type and Options



13.4.3.6 Create Plate with Hole

13.4.3.7 Mesh the Areas

13.4.3.8 Define Symmetry Boundary Conditions

13.4.3.9 Define Pressure Load along Right Edge.

13.4.3.10 Define Convergence Criteria

13.4.3.11 Solve the Problem


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13.4.3.12 Review the Results and Exit ANSYS

13.5 Sample p-Method Analysis (Command or Batch Method)

14 Explicit Dynamics Analysis

14.1 Overview of ANSYS/LS-DYNA Explicit Dynamics

14.2 Commands Used in an Explicit Dynamics Analysis

14.3 Overview of Steps in an Explicit Dynamics Analysis

14.3.1 Build the model



14.3.2.1 Loads

14.3.2.2 Initial Velocities

14.3.2.3 Constraints

14.3.2.4 DOF Coupling

14.3.2.5 Data Smoothing




14.3.3.3 Reviewing Results Using POST26


14.3.3.5 Reviewing Results Using POST1


14.3.3.7 Option: Display Animated Shapes





14.4 Where to Find Explicit Dynamics Example Problems

14.5 Sequential Solutions


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14.5.1 Explicit-to-Implicit Sequential Solution

14.5.2 Implicit-to-Explicit Sequential Solution

14.6 Additional Information


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ANSYS Structural Analysis Guide Table of Contents

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