Projekt zur Bestimmung von Absorptionsgrad und Durchgangsdämpfung in der Entwicklungsphase von Verkleidungspaneelen
The goal of this project, which was funded by Hessen Agentur, was to support and develop fireproof, sound-absorbing materials. The important considerations were the early evaluation of the various materials and their composition in the development phase.
Generally, several square meters of test material are required to determine the sound absorption coefficient. The materials are then examined in a specially constructed reverberation room. During the new development phase, however, there is either not always enough material available or the fabrication of the material is too expensive.
The Research Group SzM, therefore, worked with a manufacturer of sound-absorbing wall panels to practically and rapidly determine sound absorption coefficients, even for small samples. This provides an estimate during the development phase as to whether further development is worthwhile and if the required level of quality can be reached.
A Kundt’s tube was used in the first step of this process in order to determine the absorption coefficient of a 50 cm2 surface. In this process, the typical use of a Kundt’s tube is based on the measurement of standing waves, which occur due to partial reflections at the test material in the pipe.
With help from new evaluation software in our Research Group and a modified measuring arrangement, it is possible to take a measurement in only a few seconds without needing to change the measurement geometry. This process allows all frequencies to be evaluated at the same time, which saves a lot of time.