STUDY OF TUNED-VIBRATION-ABSORBER-BASED HYBRID PANEL TO IMPROVE ACOUSTICS INSULATION IN LOW FREQUENCY

• Main Author: Kusuma Raharja Salikim, Hans
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/61151
• Institution: Institut Teknologi Bandung

Single panel acoustic insulation has been known to have low sound transmission loss (STL) values around the first panel resonance frequency. This causes the panel’s resistance against sound sources worse in low frequencies than in mid-high frequencies (above 250 Hz), which is proportional to the product of its mass and frequency. Generally, usage of high-density materials, acoustic absorbers, and double panel configuration are used in order to improve the STL. However, these approaches don’t solve the problem around the first panel resonance frequency as it is also affected by panel stiffness. In some cases, high-density materials, absorbers, and double panel configuration aren’t always applicable because of limitations in other technical disciplines such as maximum allowable load, space, and environment. Within this final project, hybrid panel is developed by integrating the concept of air-borne and structure-borne noise control within one panel system to solve the STL problem in low frequencies. Within its development, tuned vibration absorber (TVA) is applied on the modeled panel and is simulated numerically with finite element method (FEM). COMSOL 5.6 software is used to implement said method to compute acoustic and dynamic structural parameters, including mobility, radiated sound power, and STL for analysis purposes. Some analytical computation is also used to validate the results. It is found that the STL around the first panel resonance frequency rises significantly, while the overall STL also increases. The same result is observed upon using double panel configuration, STL increase happens around the first panel resonance frequency and above the mass-air-mass resonance frequency. In hybrid double panel case, TVA implementation is more proper because the second insulation panel can protect the TVA on the first panel. Thus, hybrid panel is an applicable solution to low frequency noises.