The acoustic sealing of holes and slits in walls

摘要: The sound transmission through circular holes and long slits in a wall of finite thickness is computed for oblique plane waves. These openings may be filled by porous absorber materials and/or they sealed at their end planes plastic sealing layers. are modelled acoustic characteristic data (propagation constant wave impedance) the layers represented masses. analysis treated as boundary problem. final quantities coefficient or loss. Numerical results show influence design parameters. It found that performance with cannot approximated empty open slits. As result these studies it recommended to use loss hole reduced its cross-sectional area slit width quantities, once such should standardized. losses nearly independent under most conditions parameters frequency.