Sound absorption coefficient of direct piercing carved wood panel with uniform geometric patterns

Abstract

Direct piercing carved wood panels (DPCWP) have been used as part of the wall panel for mosques in this country. Among the earliest used of DPCWP is as in Masjid Sultan Zainal Abidin in 1700s, Kuala Terengganu, Terengganu. It is envisage, the use of DPCWP is to help in achieving good speech intelligibility inside. This is considering DPCWP allowing sound waves to pass through, hence sound reflection to the main prayer is contain. Minimizing sound reflection toward the mosque main area, ensuring optimization of speech intelligibility. DPCWP has the ability to allow sound waves to pass through the panel. This qualifies DPCWP as sound absorber material. This as Sabine, Kutruff and Maekawa definition of sound absorption coefficient. In this paper the sound absorption coefficient of DPCWP with uniform geometric patterns are discussed. The perforation ratios are 31% and 37%. Numerical experiments were conducted using Boundary Element Method (BEM). The measured results were obtained using sound intensity measurements technique. Comparison of sound absorption coefficient obtained through numerical experiment and measured using sound intensity are discussed in details. Analysis of resonance frequencies due to types and sizes of apertures in relation to sound absorption coefficient also highlighted. The measured and numerical results suggest, DPCWP of uniform geometric patterns indeed able to act as good sound absorber. This finding allows DPCWP to be used as sound absorber more effectively in future mosque construction.

Normal Incidence Sound Absorption Coefficient of Direct Piercing Carved Wood Panel with Daun Sireh Motif using Boundary Element Method

“…The comparison suggests that all perforation ratios have better at lower frequency. At 250 Hz and 500 Hz, the results are the highest, which is similar compared with our previous work (Dimon et al, 2010). Further statistical analysis was performed to determine the rate of relative error of the approximation of the SAC performance based on the BEM results.…”

“…The modeling process began with the 2.1 m line creation at the front side of the floral panel. The distance for the back panel room from the DPCWP is 0.77 m. Based on our parametric study (Dimon et al, 2009c), one-quarter size of the DPCWP with DSM is sufficient to investigate the SAC performance. Figure 4 shows the complete quarter size anechoic room with DPCWP with DSM.…”

“…All distances refer to the 0.25 sound wavelength (λ) of each frequency, except for 4 kHz, because the distance was too close to the surface and thus, the distance was adjusted to 1.25 λ. The distances were chosen to correspond with former measurement techniques conducted in anechoic chambers (Dimon, 2002;Dimon, 2006;Dimon, 2009b). The sound pressure level was set to 0.25λ to minimize the error in obtaining sound intensity values.…”

“…However, the wood carvers may use their own creativity to generate intricate floral elements in their product. While numerous studies have been proposed to measure the sound absorption coefficient (SAC) of DPCWP (Ula, 2006;Dimon, 2009a), the databases for DPCWP with floral pattern are still inadequate. The investigation and estimation of the SAC of perforated panels has become an important topic in acoustic research (Lin et al, 2008); hence, it is important to investigate the SAC of the DPCWP with floral pattern.…”

Pembiasaan Sholat Berjamaah Sebagai Penguatan Karakter Religius

“…Adzim, Kholilul Ahmad; Konsep Pendidikan Karakter Anak Berbasis Keluarga Islami Era Society 5.0. Journal Ta'limuna STAI Ma'had Aly Al Hikam Malang, Vol.…”