Engineering Analysis with ANSYS Software

Preface     xiiiThe Aims and Scope of the Book     xvBasics of finite-element method     1Method of Weighted Residuals     2Sub-domain method (Finite volume method)     2Galerkin method     4Rayleigh-Ritz Method     5Finite-Element Method     7One-element case     10Three-element case     11FEM in Two-Dimensional Elastostatic Problems     14Elements of finite-element procedures in the analysis of plane elastostatic problems     15Fundamental formulae in plane elastostatic problems     16Equations of equilibrium     16Strain-displacement relations     16Stress-strain relations (constitutive equations)     17Boundary conditions     19Variational formulae in elastostatic problems: the principle of virtual work     21Formulation of the fundamental finite-element equations in plane elastostatic problems     21Strain-displacement matrix or [B] matrix     21Stress-strain matrix or [D] matrix     25Element stiffness equations     25Global stiffness equations     27Example: Finite-element calculations for a square plate subjected to uniaxialuniform tension     30Bibliography     34Overview of ANSYS structure and visual Capabilities     37Introduction     37Starting the Program     38Preliminaries     38Saving and restoring jobs     40Organization of files     41Printing and plotting     42Exiting the program     43Preprocessing Stage     43Building a model     43Defining element types and real constants     44Defining material properties     46Construction of the model     47Creating the model geometry     47Applying loads     48Solution Stage     49Postprocessing Stage     50Application of ANSYS to Stress Analysis     51Cantilever beam     51Example problem: A cantilever beam     52Problem description     53Review of the solutions obtained by the elementary beam theory     53Analytical procedures     53Creation of an analytical model     53Input of the elastic properties of the beam material     56Finite-element discretization of the beam area      57Input of boundary conditions     62Solution procedures     71Graphical representation of the results     73Comparison of FEM results with experimental ones     76Problems to solve     76Procedures for Creating Stepped Beams     80Creation of a stepped beam     80How to cancel the selection of areas     81Creation of a stepped beam with a rounded fillet     81How to display area numbers     84The Principle of St. Venant     84Example problem: An elastic strip subjected to distributed uniaxial tensile stress or negative pressure at one end and clamped at the other end     84Problem description     85Analytical procedures     85Creation of an analytical model     85Input of the elastic properties of the strip material     86Finite-element discretization of the strip area     86Input of boundary conditions     88Solution procedures     89Contour plot of stress     92Discussion     92Stress Concentration Due to Elliptic Holes     93Example problem: An elastic plate with an elliptic hole in its center subjected to uniform longitudinal tensile stress [sigma][subscript o] at one end and damped at the other end     93Problem description     94Analytical procedures     94Creation of an analytical model     94Input of the elastic properties of the plate material     97Finite-element discretization of the quarter plate area     98Input of boundary conditions     99Solution procedures     100Contour plot of stress     101Observation of the variation of the longitudinal stress distribution in the ligament region     101Discussion     102Problems to solve     105Stress Singularity Problem     106Example problem: An elastic plate with a crack of length 2a in its center subjected to uniform longitudinal tensile stress [sigma][subscript 0] at one end and clamped at the other end     106Problem description     106Analytical procedures     107Creation of an analytical model     107Input of the elastic properties of the plate material     110Finite-element discretization of the centercracked tension plate area     110Input of boundary conditions     113Solution procedures     114Contour plot of stress     115Discussion      116Problems to solve     118Two-Dimensional Contact Stress     120Example problem: An elastic cylinder with a radius of length (a) pressed against a flat surface of a linearly elastic medium by a force     120Problem description     120Analytical procedures     121Creation of an analytical model     121Input of the elastic properties of the material for the cylinder and the flat plate     123Finite-element discretization of the cylinder and the flat plate areas     123Input of boundary conditions     133Solution procedures     135Contour plot of stress     135Discussion     136Problems to solve     138References     141Mode Analysis     143Introduction     143Mode Analysis of A Straight Bar     144Problem description     144Analytical solution     144Model for finite-element analysis     145Element type selection     145Real constants for beam element     147Material properties     147Create keypoints     149Create a line for beam element     151Create mesh in a line      152Boundary conditions     154Execution of the analysis     157Definition of the type of analysis     157Execute calculation     159Postprocessing     161Read the calculated results of the first mode of vibration     161Plot the calculated results     161Read the calculated results of the second and third modes of vibration     161Mode Analysis of a Suspension for Hard-Disc Drive     163Problem description     163Create a model for analysis     163Element type selection     163Real constants for beam element     165Material properties     168Create keypoints     168Create areas for suspension     171Boolean operation     175Create mesh in areas     177Boundary conditions     179Analysis     182Define the type of analysis     182Execute calculation     182Postprocessing     183Read the calculated results of the first mode of vibration     183Plot the calculated results     183Read the calculated results of higher modes of vibration     184Mode Analysis of a One-Axis Precision Moving Table Using Elastic Hinges     188Problem description     188Create a model for analysis     189Select element type     189Material properties     189Create keypoints     192Create areas for the table     193Create mesh in areas     197Boundary conditions     201Analysis     205Define the type of analysis     205Execute calculation     208Postprocessing     209Read the calculated results of the first mode of vibration     209Plot the calculated results     209Read the calculated results of the second and third modes of vibration     210Animate the vibration mode shape     211Analysis For Fluid Dynamics     215Introduction     215Analysis of Flow Structure in A Diffuser     216Problem description     216Create a model for analysis     216Select kind of analysis     216Element type selection     217Create keypoints     219Create areas for diffuser     221Create mesh in lines and areas      222Boundary conditions     226Execution of the analysis     231Flotran set up     231Execute calculation     233Postprocessing     234Read the calculated results of the first mode of vibration     234Plot the calculated results     234Plot the calculated results by path operation     237Analysis of flow structure in a channel with a butterfly Valve     242Problem description     242Create a model for analysis     242Select kind of analysis     242Select element type     243Create keypoints     243Create areas for flow channel     245Subtract the valve area from the channel area     245Create mesh in lines and areas     246Boundary conditions     248Execution of the analysis     251Flotran set up     251Execute calculation     253Postprocessing     254Read the calculated results     254Plot the calculated results     255Detailed view of the calculated flow velocity     256Plot the calculated results by path operation     259Application of ANSYS to Thermo Mechanics     263General characteristic of heat transfer problems     263Heat transfer through two walls     265Problem description     265Construction of the model     265Solution     276Postprocessing     280Steady-State Thermal Analysis of a Pipe Intersection     285Description of the problem     285Preparation for model building     288Construction of the model     291Solution     298Postprocessing stage     306Heat Dissipation Through Ribbed Surface     312Problem description     312Construction of the model     313Solution     321Postprocessing     325Application of ANSYS to Contact Between Machine Elements     331General Characteristics of Contact Problems     331Example Problems     332Pin-in-hole interference fit     332Problem description     332Construction of the model     333Material properties and element type     338Meshing     339Creation of contact pair     342Solution      347Postprocessing     352Concave contact between cylinder and two blocks     359Problem description     359Model construction     360Material properties     365Meshing     368Creation of contact pair     372Solution     374Postprocessing     379Wheel-on-rail line contact     382Problem description     382Model construction     385Properties of material     391Meshing     392Creation of contact pair     398Solution     401Postprocessing     4040-ring assembly     410Problem description     410Model construction     412Selection of materials     413Geometry of the assembly and meshing     423Creating contact interface     427Solution     436Postprocessing (first load step)     442Solution (second load step)     444Postprocessing (second load step)     451Index     453