Finite element analysis is an analytical tool that may be used to determine loads and deflections or natural frequencies and mode shapes of equipment and structures. A finite element model is a mathematical description of the stiffness and mass of the equipment or structure. Complex systems are difficult to model accurately, however, and a means to validate a mathematical model would ensure results credibility. Impulse testing is a means by which natural frequencies and mode shapes can be determined experimentally. The process involves determining the transfer function, or the ratio of a measured response of a structure to a specific input in the frequency domain. Natural frequencies and mode shapes can be scaled from the transfer function results. When impulse testing was used to validate a mathematical analysis of a cantilever beam, results showed that the rigid boundary condition used in the mathematical model was stiffer than the experimental results indicated. By relaxing the boundary condition in the mathematical model of the structural problem, the analytically determined frequencies and mode shapes were found to correspond with the experimentally determined results.
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