Vibration Control and Engineering

Introduction

There are numerous sources of vibration in the industrial environment, and its presence often has undesirable affects such as mechanical or structural fatigue or failure; these are reasons for vibration control engineering!

Control Methods

In many practical scenarios, it's possible to mitigate the dynamic forces that cause vibrations.

Several methods are used to mitigate and control vibrations, and the options are as follows:

By controlling the natural frequencies and mode shapes of the system/structure of the machine, equipment etc. and avoiding resonances under external excitation.
By suppressing excessive response of the system, even at resonances, by providing a damping or energy dissipating mechanism.
By reducing the transmission of the excitation forces from one part of the machine to another, by the use of a resilient member, like an isolation mount or anti-vibration mount.
By reducing the response of the system, by adding an auxiliary mass as a neutraliser or a vibration absorber.

Vibration Control Engineering

NaVCaE Ltd is an acoustic and mechanical engineering consultancy that resolves noise and vibration problems.

To solve vibration problems, we first understand the problem by modelling the behaviour using measured vibration data and then update the analytical model to get the desired structural dynamics for more favourable vibration.

This is a method used to achieve more favourable vibration levels. Another method is Vibration Isolation, in which we provide passive vibration isolation solutions.

Vibration Control vs Vibration Isolation

Vibration isolation is a mechanism to isolate the vibration from propagating further into the structure or neighbouring structures, by typically using isolation mounts or anti-vibration mounts.

For this mechanism to be effective, the operating frequency must be more than three or greater times than that of the resonance frequency of the mass on the isolation mounts.

The effectiveness of the isolation is also dependent on the damping of the mount.

What if the operating frequency varies, is not fixed and it is not possible to specify an isolation mount?

This is when controlling vibration is the only option. Vibration can be mitigated by design optimisation.

Let's present a case study.

This case study is about a fabricated electronic distribution box that was developed for Dassault Aviation's Falcon 7X.

Dassault Aviation did not permit vibration mounts (as the rubber degrades over time, and is not strong enough for crash safety) or air movers (fans for cooling the electronics) in their aircraft equipment.

…and the greatest challenge, to keep the weight down, as the lighter the plane, the cheaper the operating cost.

So vibration control was the only option.

The box was engineered to sustain the brunt of the aircraft vibration, by optimising the design of the box, i.e. the printed circuit boards (PCB) were structurally optimised to mitigate the vibration levels to which the electronic components were subjected.

The positioning of the stand-off pillars (between the box base and the PCBS) were placed strategically to avoid the high vibration areas of the base of the box.

Successful vibration testing was proof that vibration engineering was effective.

How can we help you?

As NaVCaE Ltd, we can help with the design of products that are subjected to unfavourable vibration levels by vibration engineering - making them resilient and robust to the vibration environment.

Furthermore, we can also mitigate the vibration of a structure by design optimisation.

Further information

If you require assistance with designing equipment or machinery subjected to vibration, please call us and speak to our engineers about vibration control, we are very forthcoming and helpful.

We are constantly adding our case studies to this website, so please return to see how we help our clients.