Silencers and sound absorbers

The increasing awareness of noise is leading to a worldwide demand for noise-reduced installations and devices of various sizes. Silencers play a major role when it comes to components for comprehensive sound insulation concepts. Our experts help industrial partners to sustainably develop innovative silencers for demanding applications.

Silencer development

Depending on the application, silencers are frequently subjected to extreme temperatures, fluctuating humidity or aggressive chemicals. Under these conditions, the use of conventional silencers is in many cases not a viable option. A further problem is reducing low-frequency noise, as this usually calls for silencers with large space requirements.

Our experts in noise control have extensive experience in developing special silencers for low-frequency noise issues and particularly demanding applications. The range extends from robust, cleanable duct silencers and sound-absorbing internal flues for steel chimneys and fireplaces right up to broadband strip absorbers integrated directly into boilers.

To suppress noise in sound-bearing ducts, we develop compact active silencers based on the principle of active resonators featuring electronic feedback and feed-forward ANC (Active Noise Cancellation)  . These silencers are used in ventilation and air-conditioning equipment, as well as in the exhaust ducts of heating systems.

When developing new silencers, we take not only the geometry and materials into account but also the impact on the respective environment. Taking a global approach, we use a series of calculation tools - both commercial tools and ones we have developed ourselves - to predict acoustic and aerodynamic parameters such as insertion loss, pressure loss, and flow noise.

Our wind tunnel enables us to validate design results directly by measurements on prototypes, to compare the underlying calculation models and to derive measures for further developments.

Silencer design

To assist our industrial customers in their development processes, we also design silencers as part of our services. Over the years, we have developed various analytical methods for silencers. Based on these, we created the software “IBP Sound” for calculating absorption silencers. For silencers with complex geometries, we use the finite element method COMSOL Multiphysics®.

Silencer testing

For different sizes and types of splitter silencers and duct silencers, we can measure insertion loss with and without superimposed flow, as well as pressure loss coefficients and flow noise according to DIN EN ISO 7235 in our very own silencer test facility. We also offer these tests to our customers as a development support service.

In addition, we offer further services related to the following research and development fields:

• Active silencers for ventilation and air-conditioning systems
• Active silencers for window systems
• Chemically-resistant absorber materials