Technical equipment and devices

Microphone in reception room silencer test bench
© Fraunhofer IBP
Microphone in reception room silencer test bench

Determination of relevant acoustic parameters and properties for sustainable product optimization#

A particular feature of high-quality installations and devices is excellent acoustics. With this in mind, our experts determine acoustic parameters and assist companies in a variety of ways to develop and test acoustically-optimized products.

Product optimization

Based on metrological investigations, simulations and our extensive acoustic know-how, we develop product-specific suggestions for improvement that are tailored to customer requirements. Within the scope of our project work, we also build functional samples and models and conduct extensive tests on them in our laboratories.

Measurement-based noise source characterization

To develop suggestions for improvements, the acoustic properties of installations and devices generally need to be examined in detail. Their sound radiation characteristics can be analyzed in the anechoic chamber. In addition to conventional multi-channel measurement systems and microphone arrays, acoustic camera systems and near-field holography are used to localize and identify dominant sources of noise.

To characterize structural vibration and its influence on sound radiation, we perform structure-borne sound measurements with classical acceleration sensors or laser vibrometers.

Measurement-based material characterization

Depending on the application and frequency range, our experts determine the sound absorption coefficient of sound-absorbing materials and components for vertical sound incidence in impedance channels of different magnitudes according to DIN EN ISO 10534-2, and for diffuse sound incidence in reverberation chambers according to DIN EN ISO 354.

Acoustic and vibro-acoustic simulation

To develop product-specific acoustic improvements, we perform finite element simulations (FEM) and parameter studies with COMSOL Multiphysics® and compare them with results from experiments.

Determination of sound power

Sound power is a device-specific acoustic parameter that often serves as a basis for implementing legal requirements. Our experts usually determine the sound power of devices under diffuse-field conditions in the reverberation chamber according to ISO 3741, or under free-field conditions in anechoic chambers according to ISO 3745.

Determination of pressure loss from single components

The loss in pressure from components used in heating, ventilating and air conditioning systems (HVAC) and process air conditioning systems is a parameter of energy efficiency. Pressure losses from silencers, air outlets, weather protection grilles, etc., can be determined in our institute's silencer test facility according to DIN EN ISO 7235.

Determination of silencer characteristics

In the equipment industry, silencers are frequently used to reduce process-related noise. In our silencer test facility, we determine insertion loss with and without superimposed flow, pressure loss coefficients and flow noise according to DIN EN ISO 7235 for splitter silencers and duct silencers of different types and sizes.