Reduction of sound transmission across plenum windows by incorporating an array of rigid cylinders

摘要: Abstract The potential improvement of plenum window noise reduction by installing rigid circular cylinder arrays into the cavity is investigated numerically using finite-element method in this study. A two-dimensional approach adopted. sound transmission characteristics and propagation within are also examined detail. Results show that installation cylinders general gives rise to broadband across a regardless direction incidence. Such acoustical performance becomes better when more columns installed, but it suggested number rows should not exceed two. positions relative nodal/anti-nodal planes acoustic modes crucial enhancement mechanisms. Noise can further be enhanced staggering rows, such each row supports development different mode. For simple arrangements considered study, traffic observed study as high 4–5 dB, which already comparable or higher than maximum achieved absorption window.