This preview shows pages 1–9. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Objectives: Formulations of FiniteElement Methods (FEM). FiniteElement Modelling and mesh generation (several approaches). Case Study. FiniteElement Modelling and Analysis Ch. 8 CAE software used to analyze kinematic and dynamic responses of assemblies being designed. Recall examples DADS and ADAMS. Examples of FiniteElement tools NASTRAN and ANSYS. Early applications of Finite Element methods (FEM) in structural mechanics plane stress analysis. Current applications include heat transfer, electrostatic potential, fluid mechanics, vibration analysis , etc. Introduction to FiniteElement Analysis (FEA) Introduction to FiniteElement Analysis (FEA) Figure 8.1 Application of the finiteelement method to analyze temperature distribution. Application is for door handle of refrigerator to calculate temperature distribution after injection mold filled with molten resin. Examples of software CMOLD and MOLDFLOW. Introduction to FiniteElement Analysis (FEA) Figure 8.2 Problems that cannot be solved analytically. (a) Cantilever beam difficulty increases if composed of many materials. (a) Temperature distribution in an object. Introduction to FiniteElement Analysis (FEA) Figure 8.3 Approximation of each object by an assemblage of finite elements. (a) Cantilever beam problem approximation using triangular elements. (a) Object approximated by quadrilateral elements for solving temperature distribution. Several finite elements may be chosen to approximate object. Depending on problem, choice of proper element(s) important. Size of elements also matter of engineering judgement. In general, larger the number of elements ( h version) or higher the degree of shape function ( p version) = greater the accuracy, but greater the computational expense. Other problems mesh generation for 3D objects of complex geometry labour intensive. Software available to automate mesh generation (ex., Altair Hypermesh) Introduction to FiniteElement Analysis (FEA) Once object approximated by finite elements, nodes associated with unknowns to be solved (ex., x and y displacements for cantilever beam). Displacement of element derived from displacement at nodes by presumed shape function of element thus only displacements at nodes are unknowns. Strains derived from partial derivative of displacement function, and stresses computed from strains. Introduction to FiniteElement Analysis (FEA) Material properties specified for each element, and boundary conditions imposed. Different material properties for different elements allow analysis of object comprising of different regions of various materials....
View
Full
Document
 Spring '09
 vinhquan
 Finite Element Method

Click to edit the document details