An introduction to Ansys A seminar on
Content • Introduction • A simple example • Steps involved • Brief explanation of element types • Analysis in ansys • Summary
Introduction to Ansys • It is an engineering simulation software developed in 1970 by Dr. John A. Swanson • It was developed to use finite element analysis to solve structural problems. • At present it is a leading software which can be used for structural, thermal, electrical, fluid problems, as well as to simulate biological components.
An example of simple cylinder under tensile loading. Material: Aluminium Yield stress: 11 Mpa Young’s Modulus: 70 Gpa Poisson’s ratio: 0.35 Diameter= 20 mm Length= 100 mm
Stress induced due to gradual tensile load of 3000 N on Z direction is • Stress = 3000/314.28 = 9.54 Mpa e = stress/E = 9.54/70000 dl = L*e = 9.54x100/70000 = 0.013628 mm
Steps involved • Creation of CAD model • Selection of suitable element type. • Selecting suitable material properties. • Mesh generation • Defining boundary conditions • Generate a solution • Analyze results
Element types • Link element It is a simple element which takes uniaxial loading that is compression or tension. It has 2 nodes per element, with 2 degrees of freedom per node. Ux and Uy
2. Beam element is a uniaxial element with tension, compression, and bending capabilities. It has 2 nodes per element, with 6 degree of freedom per node. Ux, Uy, Ux, Rot x, Rot y, Rot z 3. Pipe element Similar to beam element but with tension, compression, torsion and bending capabilities
4. Solid This element is used to mesh a 3D model. Its subtypes are quadrilateral and tetrahedral. Quadrilateral 4 node 8 node Tetrahedral 4 Node 10 Node
Brick 8 node 20 node
Material properties 1. Linear Elastic Isotropic Orthotropic Anisotropic 2. Non-linear Elastic Inelastic Viscoelastic 3. Density 4. Thermal expansion 5. Damping 6. Friction coefficient
Mesh generation • Discritizing the model into number of elements is called as meshing. • Validity of analysis greatly depends on meshing. • Finer mesh >> more accurate results >> more computational time
Modeling of cylinder • Element selected Link • Material properties • Poisson’s ratio 0.35 • Young’s modulus 70000 Mpa • Force applied 3000 N
Summary • Brief steps in finite element analysis using Ansys • Introduction to Ansys, various element types. • Comparison between exact results and results obtained using FEA.
References • M. A. Maleque and M. S. Salit, “Materials Selection and Design”, SpringerBriefs in Materials, DOI: 10.1007/978-981-4560-38-2_2. • A.E. Tekkaya, P.A.F. Martins, (2009) "Accuracy, reliability and validity of finite element analysis in metal forming: a user's perspective", Engineering Computations, Vol. 26 Iss: 8. • Ansysmodeling and meshing guide. • http://mostreal.sk/html/elem_55/chapter4/ • http://web.mit.edu/calculix_v2.4/CalculiX/ccx_2.4/doc/ccx/