The modern automotive industry is characterised by efficiency. Ever lower consumption regulations are compelling car manufacturers to turbocharge their combustion engines. This air charging leads to an increase in the noise levels. As acoustic specialists, we are in a position to develop the best solution for reducing undesired noises of all kinds. In particular, we are able to efficiently reduce the noise generated by the compression of air (turbocharging). Without noise reduction measures, this unwanted noise propagates towards the ducts and can ultimately be perceived by the passengers. With Umfotec resonators, the unwanted noise can be reduced by up to 95%.

We design our high-efficiency resonators using stainless steel, aluminium or plastic according to requirements. Material combinations are also used. Our broad-based manufacturing capability provides every option for producing the best possible resonator. 


Resonators in the fight against undesired noise

As already mentioned above, the compression of air by turbocharged engines does not take place noiselessly. The noises that are produced then propagate towards the ducts with very little damping to the charge-air cooler. The noise level is perceived by the passengers as unpleasant. Typical noises are pulsating or rushing/hissing noises. As a rule of thumb: the higher the degree of compression of the air, the higher the sound level and the charge-air temperature. 

Our resonators reduce undesired noises (tonal and broadband) to a minimum. 

How do we go about this? 

First of all, the acoustic specification, that is, the insulation value and the frequency range in which the resonator is to operate, needs to be defined. UMFOTEC resonators can, for example, almost completely deaden noise in the range from 1,000 to 4,000 Hz. Our challenge often lies in achieving the optimum noise reduction in the specified frequency range in a given installation space.  Sometimes the space available for the resonator and the desired noise reduction level in the specified frequency range do not match – in this case Umfotec works out the best acoustic compromise.

The resonators are designed by us in close consultation with our customers. As a result of this, there are innovative charge-air resonators for applications from about 600 Hz upwards. Please do not hesitate to contact us, and we will be happy to explain the options, preferably in person. 

We are receiving an increasing number of requests for high-frequency applications above 5,000 Hz. Classical Helmholtz resonators cannot be designed for use in this range. Using the patent Umfotec solution “seal-less resonator”, our developers have succeeded in tuning high-frequency resonators with low pressure loss up to 10,000 Hz and higher. Another innovation from the UMFOTEC team.