Development of ventilation and sound insulation materials by the multi-objective optimization

Natural ventilation-based houses in tropical countries often suffer from poor acoustic performance. To address this issue, we developed ventilation and sound-absorbing materials using a multi-objective optimization program. The program was developed to design test specimens that optimize the sum of the flow velocities of all elements of the divided cylindrical 3D model for sound-absorbing ability and the sum of the flow velocities in the bottom elements of the model for ventilation ability, with the objective of maximizing both. By outputting the specimens using a 3D printer, we were able to select materials suitable for the installation environment without requiring individual design changes. In this report, we focus on improving the sound insulation rate by refining the objective functions used to create the specimens. We measured the transmission loss using a self-made impedance tube and the 4mic method and verified the validity of our programming results by comparing them with those of laboratory experiments. Our approach has the potential to improve the acoustic performance of natural ventilation-based houses in tropical countries, making them more comfortable and conducive to living and working.