febi: NVH in the Car: What’s Behind It
NVH – this abbreviation is used again and again when it comes to annoying vibrations in the vehicle. But, what do these three letters stand for? They stand for “Noise, Vibrations, and Harshness”. This refers to all disruptive noises and vibrations that can be felt or heard during a car journey. Here is a more precise look into the three letters:
Noise is defined as the unpleasant or disruptive sound that causes some sort of disturbance – such as the rattling of a worn bearing.
Vibrations are defined as the off-putting, repetitive motion of an object, such as a tire out of balance.
Harshness is a tad more difficult to define as this is very subjective. However, it could be defined as a sudden, aggressive feeling, such as the sensation of driving through a pothole.
Preventing NVH
NVH reduction has become a technology in itself. The goal of vehicle manufacturers is to reduce NVH in their vehicles as much as possible with the help of rubber-to-metal insulators and vibration damping measures.
When replacing any mounting or insulator, it is important to consider what it is made of and how it is designed as these factors can dramatically affect the vehicle’s natural feel and driving behavior.
Flexible vs. Hard
The stiffness or rigidity of a vibration damper, for example, influences the natural frequency. The stiffer the vibration damper means it gives a higher natural frequency, giving a more dynamic, but “harsh” feedback. The more flexible the vibration damper, the lower natural frequency. This leads to a more typical “insulated” reaction.
A part that has been manufactured with the incorrect materials will have a dramatic effect on the service life of any directly connected components. For this reason, you should only rely on products in OE matching quality.