Engineering analyses in CAD or integrated Computer Aided Engineering (CAE) tools,are analytical where experiments are simulated through software 3.Computational mechanics is one of the earliest CAE applications and appliesmechanics, mathematics, and numerical methods to simulate the physical behaviorof engineering artifacts 35. CAD workstations visualize large amounts of data andcomplex analyses for efficient interpretation 3. 3D CAD models are analyzedthrough integrated CAE tools including finite element stress distributions, simulatedautomobile crash testing, and digital human modeling 2,3,5,8.
Solidworks RKS2017, CATIA V5, NX 10, Autodesk Fusion 360, and Autodesk AutoCAD offer a varietyof CAE/CAM capabilities including structure, static stress, fluid, thermal dissipation,dynamic response, parametric optimization, and digital humanmodeling/ergonomics analyses 15 -34. Engineering analyses in CAD or integrated CAE tools are analytical whereexperiments are simulated through software 3. Simulation is used for designverification and performance optimization including the crashworthiness of vehicles8. Experimental testing of physical prototypes is primarily used to assess materialproperties and validate design performance, and is especially useful when analyticalmodels are not possible 3. Conventional design testing often involves post-manufacturing quantification and late-stage physical prototypes while CAD/CAEallows testing to be done throughout the design process and supportsmultidisciplinary design analyses 2,3,8,10,40,42. Finite element models (FEM)/finite element analysis (FEA), solid models, andcomputer simulations are some of the most popular forms of engineering analysesin design 6,42. Finite element modeling has been used in many engineering fieldsto solve complex analyses by dissolving models into constituent problems that arereadily solvable 3,8,10.
Finite element models are also frequently used to crosscheck experimental results and identify necessary modifications 3. Finite elementanalysis (FEA) performs stress, strain, and heat transfer calculations bydisassembling complex objects into basic components that are easier to solve; amesh of constituent components 2,3,6,7,8. 3D CAD solid and surface models allowFEA meshes to be readily implemented and tested with automatic mesh generationfor CAD models, introducing analyses earlier in the design process 8. FEMs allowengineers to modify designs and analyze their performance with lower time andcost investments 6. FEA can be used to analyze a wide variety of physicalbehaviors including stress, strain, temperature distribution, fluid flow, andelectric/magnetic fields 7,8,35. Assumptions and material properties should be well understood when usingFEA/FEM. Results and assumptions must be evaluated by the user; CAD or FEAsoftware cannot tell whether mesh density, element type, and material assumptionsare appropriate 8. Other determinants of FEA quality include material elasticity,element shape, stress and temperature coupling, and mesh quality 8.
Literature also suggests validating CAD files before releasing them for analysis andmanufacturing 40. For example, it was found that finite element analysis (FEA)users spend up to 70% of their time fixing invalidated CAD models, and CAD modelvalidation reduced model rework time 50 – 80% 40. Other research suggests thatFEA experts sometimes spend days importing CAD files into FEA pre-processingprograms that heal model geometry and generate structure meshes 44. FEA can further improve design quality when combined with optimization byreducing part material up to 82% to produce products with less waste 3,7. Thereare often several, if not thousands of acceptable solutions to a design problem andengineers wish to find the best of these solutions using optimization 35.