Finite-element analysis (FEA)
Finite-element analysis (FEA) is a computer numerical analysis program used to solve complex problems in many engineering and scientific fields, such as structural analysis (stress, deflection, vibration), thermal analysis (steady state and transient), and fluid dynamics analysis (laminar and turbulent flow) (Fig. 9). The finite-element method divides a given physical or mathematical model into smaller and simpler elements, performs analysis on each individual element using required mathematics,
and then assembles the individual solutions of the elements to reach a global solution for the model. FEA software programs usually consist of three parts: the preprocessor, the solver, and the postprocessor.
The program inputs are prepared in the preprocessor. Model geometry can be defined or imported from CAD software. Meshes are generated on a surface or solid model to form the elements. Element properties and material descriptions can be assigned to the model. Finally, the boundary conditions and loads are applied to the elements and their nodes. Certain checks must be completed before the analysis calculation. These include checking for duplication of nodes and elements and verifying the element connectivity of the surface
elements so that the surface normals are all in the same direction. To optimize disk space and running time, the nodes and elements should usually be renumbered and sequenced.
Many analysis options are available in the analysis solver to execute the model. The element stiffness matrices can be formulated and solved to form a global stiffness value for the model solution. The results of the analysis data are then interpreted by the postprocessor in an orderly manner. The postprocessor in most FEA applications offers graphical output and animation displays. Many vendors of CAD software are also developing pre- and postproc essors that allow users to graphically visualize their input and output. FEA is a powerful tool in effectively synthesizing a design into an optimized product.
Emory W. Zimmers, Jr. and Technical Staff
Enterprise Systems Center
Lehigh University
Bethlehem, Pennsylvania
Mechanical Engineers’ Handbook: Materials and Mechanical Design, Volume 1, Third Edition.
Edited by Myer Kutz
Copyright 2006 by John Wiley & Sons, Inc.
