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Chapter 1
1.2. Discretization means dividing the body (system) into an equivalent system of finite elements
with associated nodes and elements.
1.4. The direct stiffness method was introduced in 1941 by Hrennikoff. However, it was not
commonly known as the direct stiffness method until 1956.
1.6. As computer developed it made possible to solve thousands of equations in a matter of
minutes.
1.7. The following are the general steps of the finite element method.
Step 1
Divide the body into an equivalent system of finite elements with associated
nodes and choose the most appropriate element type.
1.8. The displacement method assumes displacements of the nodes as the unknowns of the
1.10 Three common methods used to derive the element stiffness matrix and equations are
(2) work or energy methods
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whole or in part.
(3) methods of weighted residuals
1.11. The term ‘degrees of freedom’ refers to rotations and displacements that are associated with
each node.
1.12. Five typical areas where the finite element is applied are as follows.
(1) Structural/stress analysis
(3) Fluid flow analysis
(5) Biomechanical engineering
1.13. Five advantages of the finite element method are the ability to
(1) Model irregularly shaped bodies quite easily
(3) Model bodies composed of several different materials because element equations are
evaluated individually
(5) Vary the size of the elements to make it possible to use small elements where necessary