Engineering Analysis with ANSYS Software (Second Edition)

Engineering Analysis with ANSYS Software, Second Edition, provides a comprehensive introduction to fundamental areas of engineering analysis needed for research or commercial engineering projects. The book introduces the principles of the finite element method, presents an overview of ANSYS technologies, then covers key application areas in detail. This new edition updates the latest version of ANSYS, describes how to use FLUENT for CFD FEA, and includes more worked examples. With detailed step-by-step explanations and sample problems, this book develops the reader’s understanding of FEA and their ability to use ANSYS software tools to solve a range of analysis problems. Uses detailed and clear step-by-step instructions, worked examples and screen-by-screen illustrative problems to reinforce learning Updates the latest version of ANSYS, using FLUENT instead of FLOWTRAN Includes instructions for use of WORKBENCH Features additional worked examples to show engineering analysis in a broader range of practical engineering applications Cover 1 Title Page 3 Copyright 4 Preface 5 The aims and scope of the book 6 1 - Fundamentals of the finite element method 8 Method of weighted residuals 8 Subdomain method (finite volume method) 9 Galerkin method 10 Rayleigh-Ritz method 11 Finite element method 14 One-element case 16 Three-element case 18 FEM in two-dimensional elastostatic problems 21 Elements of finite-element procedures in the analysis of plane elastostatic problems 22 Fundamental formulae in plane elastostatic problems 23 Equations of equilibrium 23 Strain-displacement relations 23 Stress-strain relations (constitutive equations) 24 Boundary conditions 27 Variational formulae in elastostatic problems: The principle of virtual work 28 Formulation of the fundamental finite-element equations in plane elastostatic problems 29 Strain-displacement matrix or [B] matrix 29 Stress-strain matrix or [D] matrix 32 Element stiffness equations 32 Global stiffness equations 35 Example: Finite-element calculations for a square plate subjected to uniaxial uniform tension 37 References 42 2 - Overview of ANSYS structure and its graphic capabilities 43 Introduction 43 Starting the programme 43 Preliminaries 43 Saving and restoring jobs 44 Organisation of files 46 Printing and plotting 47 Exiting the programme 48 Preprocessing stage 48 Building the model 48 Defining element types and real constants 49 Defining material properties 51 Construction of the model 53 Creating the model geometry 53 Applying loads 53 Solution stage 54 Postprocessing stage 55 3 - Application of ANSYS to stress analysis 56 Cantilever beam 56 Example problem: A cantilever beam 56 Problem description 57 Review of the solutions obtained by the elementary beam theory 57 Analytical procedures 58 Creation of an analytical model 58 Input of the elastic properties of the beam material 60 Finite-element discretisation of the beam area 62 Input of boundary conditions 68 Solution procedures 78 Graphical representation of the results 79 Comparison of FEM results with experimental ones 82 Problems to solve 82 Appendix: Procedures for creating stepped beams 85 Creation of a stepped beam 85 How to cancel the selection of areas 87 Creation of a stepped beam with a rounded fillet 87 How to display area numbers 90 The principle of St. Venant 90 Example problem 90 Problem description 91 Analytical procedures 91 Creation of an analytical model 91 Input of the elastic properties of the strip material 92 Finite-element discretisation of the strip area 92 Input of boundary conditions 94 Solution procedures 98 Contour plot of stress 98 Discussion 99 Stress concentration due to elliptic holes and inclusions 99 Example problem 99 Problem description 100 Analytical procedures 100 Creation of an analytical model 100 Input of the elastic properties of the plate material 104 Finite-element discretisation of the quarter plate area 104 Input of boundary conditions 105 Solution procedures 107 Contour plot of stress 107 Observation of the variation of the longitudinal stress distribution in the ligament region 108 Discussion 110 Problems to solve 111 Stress singularity problem 111 Example problem 111 Problem description 111 Analytical procedures 112 Creation of an analytical model 112 Input of the elastic properties of the plate material 115 Finite-element discretisation of the centre-cracked tension plate area 115 Input of boundary conditions 117 Solution procedures 119 Contour plot of stress 120 Discussion 121 Problems to solve 123 Two-dimensional contact stress 124 Example problem 124 Problem description 124 Analytical procedures 125 Creation of an analytical model 125 Input of the elastic properties of the materials for the cylinder and the flat plate 128 Finite-element discretisation of the cylinder and the flat plate areas 128 Input of boundary conditions 140 Solution procedures 140 Contour plot of stress 141 Discussion 143 Problems to solve 144 Three-dimensional stress analysis: Stress concentration in a stepped round bar subjected to torsion 147 Example problem: A stepped round bar subjected to torsion 147 Problem description 148 Review of the solutions obtained by the elementary mechanics of materials 148 Analytical procedures 149 Creation of an analytical model 149 Input of the elastic properties of the stepped round bar material 150 Finite-element discretisation of the round bar volume 152 Input of boundary conditions 153 Solution procedures 159 Contour plot of stress 162 Discussion 165 Problems to solve 167 References 167 4 - Mode analysis 169 Introduction 169 Mode analysis of a straight bar 169 Problem description 169 Analytical solution 170 Model for FE analysis 170 Element type selection 170 Sections for beam element 172 Material properties 173 Create keypoints 175 Create a line for beam element 175 Create mesh in a line 177 Boundary conditions 178 Execution of the analysis 185 Definition of the type of analysis 185 Execute calculation 187 Postprocessing 188 Read the calculated results of the first mode of vibration 188 Plot the calculated results 188 Read the calculated results from the second and third modes of vibration 189 Modal analysis of a suspension for hard disc drive 190 Problem description 190 Create a model for analysis 190 Element type selection 190 Material properties 192 Sections for shell element 193 Create keypoints 194 Create areas for suspension 195 Boolean operation 199 Create mesh in areas 202 Boundary conditions 203 Execute the analysis 206 Define the type of analysis 206 Execute calculation 208 Postprocessing 208 Read the calculated results of the first mode of vibration 208 Plot the calculated results 208 Read the calculated results of higher modes of vibration 209 Modal analysis of a one axis precision moving table using elastic hinges 212 Problem description 212 Create a model for analysis 213 Select element type 213 Material properties 215 Create keypoints 216 Create areas for the table 217 Create mesh in areas 223 Boundary conditions 229 Execute the analysis 232 Define the type of analysis 232 Execute calculation 234 Postprocessing 234 Read the calculated results of the first mode of vibration 234 Plot the calculated results 234 Read the calculated results of the second and third modes of vibration 235 Animate the vibration mode shape 237 5 - Analysis for fluid dynamics 238 Introduction to FLUENT 238 Analysis of flow structure in a diffuser 238 Problem description 238 Create a model for analysis using Workbench 239 Select kind of analysis 239 Preparation for DesignModeler to create a geometry for analysis 240 Create a wire frame for diffuser 243 Create surfaces for diffuser 246 Create mesh in surface for diffuser 248 Boundary conditions 252 Setup for solution and excursion of the analysis 258 Postprocessing 262 Create XY plot of air flow at a cross section of the diffuser 262 Analysis of flow structure in a channel with a butterfly valve 267 Problem description 267 Create a model for analysis using Workbench 268 Select kind of analysis (Fluent) 268 Preparation for DesignModeler to create a geometry for analysis 268 Create a wire frame for a butterfly valve 268 Create a surface for a channel with a butterfly valve 270 Create meshes for a channel with a butterfly valve 271 Boundary conditions 275 Setup for solution and excursion of the analysis 277 Postprocessing 282 6 - Application of ANSYS to thermo-mechanics 285 General characteristic of heat transfer problems 285 Heat transfer through two adjacent walls 286 Problem description 286 Construction of the model 287 Solution 299 Postprocessing 303 Steady-state thermal analysis of a pipe intersection 308 Description of the problem 308 Preparation for model building 310 Construction of the model 314 Solution 321 Postprocessing stage 333 Heat dissipation through a developed surface 337 Problem description 337 Construction of the model 338 Solution 348 Postprocessing 351 Heat conduction 355 Problem description 355 Preprocessing stage 356 Model construction 356 Solution stage 359 Postprocessing stage 361 Temperature plot 361 Solution in command mode 362 Thermal stresses analysis 362 Problem formulation 362 Thermal settings 363 Geometry and thermal properties 363 Thermal settings 368 Structural settings 368 Mechanical properties 368 Solution stage 370 Postprocessing stage 374 7 - Application of ANSYS to contact between machine elements 377 General characteristic of contact problems 377 Example problems 378 Pin-in-hole interference fit 378 Problem description 378 Construction of the model 379 Material properties and element type 384 Meshing 386 Creation of contact pair 390 Solution 394 Postprocessing 400 Concave contact between cylinder and two blocks 406 Problem description 406 Model construction 407 Material properties 412 Meshing 415 Creation of a contact pair 420 Solution 424 Postprocessing 427 Wheel-on-rail line contact 432 Problem description 432 Model construction 433 Properties of material 440 Meshing 441 Creation of a contact pair 447 Solution 452 Postprocessing 456 Contact between elements made of elastic and viscoelastic materials 461 Problem description 461 Model construction 462 Selection of materials 465 Geometry of the O-ring and meshing 468 Creating wall and groove 471 Creation of a contact pair 477 Solution-First stage of loading 480 Postprocessing-First stage of loading 484 Solution-Second stage of loading 484 Postprocessing-Second stage of loading 493 Contact between two beams 493 Problem description 493 Construction of the model 495 Material properties and element type selection 496 Meshing 499 Creation of a contact pair 499 Solution 506 Postprocessing 509 Reference 511 Appendix: Using ANSYS workbench for structural analysis 512 Introduction 512 Problem description: A stepped round bar subjected to tension 512 Starting workbench 513 Creation of a 3D analysis model using the design modeller 516 Stress analysis of a stepped round bar subjected to uniform tension 525 Finite-element discretisation of the round bar volume 525 Imposition of boundary conditions 527 Solution procedures 531 Contour plots of the results 535 Discussion 536 Automatic report generation 539 References 541 Index 542 A 542 B 542 C 543 D 544 E 544 F 545 G 545 H 545 I 547 J 547 K 547 L 547 M 547 O 547 P 548 Q 549 R 549 S 549 T 551 U 552 V 552 W 552 Y 552 Back Cover 553