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기존의 소화시스템에 의해 화재 진압 시 발생하는 높은 수준의 노이즈는 민감한 기계장치에 충격을 주게 되는데, 이러한 충격 노이즈를 감소시키기 위해 저소음 소화노즐 기술의 적용에 관심이 증가하고 있다. 본 연구에서는 기존 소화시스템의 소화노즐과 소음 감쇄기구를 구비한 소화노즐의 소음특성을 비교하였다. 본 연구에서는 기존에 출시된 저소음 소화노즐의 방출소음을 예비적으로 측정하였다. 그리고 새로운 유형의 저소음 소화노즐로 개발 가능성을 파악하기 위해 Table 1에 정리한 바와 같이 총 9개의 case로 준비하였다. 소음을 저감시킬 수 있는 설계 요소는 오리피스 압력강하 특성을 대표하는 방출구의 크기(지름, 길이, 개수, 총 면적 등)와 소음 감쇄재, 반사 및 공명 유로설계 등으로 파악되었다. 또한 이들 각 요소간의 상호작용으로 소음이 감소하는 특성을 보였다. 다양한 형상설계와 소음 감쇄재를 적용한 본 예비실험의 경우를 비교하여 case 8에서 96.4 dB의 소음치를 확인하였다. Case 7 대비 case 8과 case 9는 소음 감쇄재 증가, 노즐 전단에 가스 충돌반사 및 우회 유로를 형성하여 최고 소음치가 크게 개선되는 특성을 보였다.
The high level of noise generated by fire extinguishing by existing fire extinguishing systems impacts sensitive machinery, and there is increasing interest in applying low noise extinguishing nozzle technology to reduce such shock noise. In this study, the noise characteristics of the extinguishing nozzle of the existing extinguishing system and the extinguishing nozzle with noise attenuation mechanism were compared. This study preliminarily measured the emission noise of the existing low noise extinguishing nozzle. A total of nine cases were prepared as summarized in Table 1 to identify the possibility of developing a new type of low noise extinguishing nozzle. The design factors that can reduce the noise were identified by the size of the release hole (diameter, length, number, total area, etc.) representing the orifice pressure drop characteristics, the noise damping material, and the reflection and resonance path design. Also, the noise is reduced by the interaction between each of these factors. By comparing the case of this preliminary experiment with various shape design and noise dampener, 96.4dB of noise was confirmed in case 8. Compared to case 7, case 8 and case 9 showed the improvement of the noise level, increase of gas collision reflection and bypass flow path in front of nozzle.
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- Publisher :The Society of Convergence Knowledge
- Publisher(Ko) :융복합지식학회
- Journal Title :The Society of Convergence Knowledge Transactions
- Journal Title(Ko) :융복합지식학회논문지
- Volume : 8
- No :1
- Pages :51-58
- DOI :https://doi.org/10.22716/sckt.2020.8.1.006
The Society of Convergence Knowledge Transactions
