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The Finite Element Method. Prof. Su-Jin Kim Gyeongsang National University. Applications of FEM. Structural analysis Heat transfer Fluid mechanics Acoustics Electromagnetic. Overview of FEM.
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The Finite Element Method Prof. Su-Jin Kim Gyeongsang National University
Applications of FEM Structural analysis Heat transfer Fluid mechanics Acoustics Electromagnetic
Overview of FEM The FEM is a numerical method for solving a system of governing equations over the domain of a continuous physical system. 구조물을 유한 개의 작은 요소(Element)들로 나누고 요소들을 연결하는 절점(Node)들의 변위를 미지수로 하는 연립방정식을 계산함으로써 변위, 변형률, 응력 등을 구하는 수치해법
Steps • Small elements subdivide the solid • Elements assemble through points on each elements called nodes • Equations for each element are the function of the unknown nodal values • Equations are combined and solved by numerical method
1D Spring Structure Elements, E Nodes, N Displacements of each node, u Applied force, F E2 E1 F N3 N2 N1
1D Spring Element Equations for each element Ep Ni Nj fpj fpi
Combined Equation Internal force, f External force, F Combined Equation
Solution Node 1 is fixed, u1=0 External force of node 2 is 0 External force of node 3 is F
3D Solids Stiffness matrix k
3D Solids A linear tetrahedron elements The assumed displacement interpolation
3D Solids A quadratic tetrahedron The assumed displacement interpolation
3D Solids A linear and quadratic hexahedron elements