frequency analysis

[Assis As]

i want to know which design is fit by using frequency analysis

[FEAnalyst]

It depends on the requirements and operating conditions of this machine. For example your structure shouldn’t have a natural frequency around 150 Hz if vibrations of this magnitude are expected during operation. Otherwise, the structure may fail due to resonance.

[Assis As]

Thank you for reply so the first one is better than other am I right ?

[FEAnalyst]

These values are just selected natural frequencies of the structure (it’s not possible to find them all). You should search for natural frequencies around the frequencies of expected excitations. In fact, you can specify the range in Hz to be searched by the eigensolver.

[Assis As]

Thank you . How can I declare value of Hz . In general how many natural frequencies are better to analyse structure fit or not .

[FEAnalyst]

In SolidWorks Simulation there are two options that you can use to limit the search for natural frequencies:
- "Upper Bound Frequency" - solver calculates only the natural frequencies below the value specified here
- "Calculate frequencies closest to (frequency shift)" - solver searches for natural frequencies around the value specified here

The number of eigenfrequencies that should be calculated depends on the case. Usually solvers find 5 lowest values but this is often not enough. In some cases you will need 10 or more.

[jayar]

Thank you for reply so the first one is better than other am I right ?

FEAnalyst is correct, it depends - that is to say that some machinery is designed such that it will pass through one or more harmonics prior to reaching its operating speed. If it were to spend too much time at a given harmonic or operate too close to one then you will see problems. If you've ever seen an unbalanced washing machine on spin cycle you will get an understanding of what might happen.

[Assis As]

Thank you very much jayar and FEAanalyst.perfectly got it