When forecasting possible failure modes or the types of analysis required to fully understand performance it is imperative to understand natural frequency. Each design has preferred frequencies of vibration, resonant frequencies, which are characterised by specific shapes of vibration.
SOLIDWORKS Simulation’s frequency analysis uses an Eigen value approach to establish the natural modes of vibration for all geometry. When a design’s natural modes and its expected surface vibration environment are too closely matched it can lead to a harmonic resonance which can result in excessive loads causing failure.
Having a strong comprehension of the design’s natural mode of vibration it is possible to run preventative measures such as material changes, component sections and mass dampers to ensure component natural frequencies do not overlap with loading environment frequencies. Consequentially the design should not only perform as desired but also have a longer service life.
To test a design’s natural frequency past the critical range you can:
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Change the geometry
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Change materials (resonant frequencies are directly proportional to the materials [Young’s (elastic) modulus]
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Modify the characteristics of the shock isolators
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Strategically place mass elements