Measurements of Scattering Coefficients Using the ISO Method in a Model Reverberation Chamber

ISO 방법론을 이용한 축소 잔향실에서의 확산계수 측정

  • 전진용 (한양대학교 건축공학부) ;
  • 이성찬 (한양대학교 대학원 건축공학과) ;
  • 류종관 (한양대학교 대학원 건축공학과)
  • Published : 2003.04.01

Abstract

The degree of diffusion, characterized by the "scattering coefficient" of surface materials, has been known to be one of the most important factors in determining the acoustical qualities of concert halls. Based on the suggested ISO method, which measures the random-incidence scattering coefficient of surfaces in a diffuse field, the scattering coefficients of different sizes and densities of wooden hemispheres and cubes were measured in model-scale reverberation rooms. As a result, wooden hemispheres with a structural depth of more than 15㎝ have the highest average (500㎐∼4㎑) scattering coefficient. It was also found that the scattering coefficient becomes higher when the diffuser density reaches about 50% for hemispheres and 30% for cubes.

콘서트홀의 음향성능을 결정짓는 중요한 요소 중의 하나로 알려진 확산현상은 실내마감재료의 "확산계수"에 의해 결정된다. 확산음장에서 임의입사 확산계수를 측정하도록 제안한 ISO (International Organization for Standardization)측정방법을 기반으로 목재 반구 확산체와 각재확산체의 크기 및 점유밀도 변화에 따른 확산계수를 축소잔향실에서 측정하였다. 측정결과 15㎝이상 높이의 반구가 가장 높은 확산계수를 보였으며, 반구의 경우 전체 점유밀도가 50%에서, 각재의 경우는 약 30% 점유에 각각 높은 확산계수를 보였다.

Keywords

References

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