밀폐용기 내부에서 발생하는 수소와 에틸렌의 폭발특성 및 압력 중첩에 관한 연구 : A Study on the Explosion and Pressure Piling of Hydrogen and Ethylene in a Confined Dome
- 발행기관 고려대학교
- 발행년도 2008
- 학위수여년월 2008. 2
- 학위명 석사
- 학과 대학원 기계공학과 기계공학전공
- 식별자(기타) DL:000018611507
- 서지제어번호 000045436923
초록/요약
A flameproof enclosure is the enclosure in which the parts which can ignite an explosive gas atmosphere such as spark and hot surface are placed and which can withstand the pressure developed during an internal explosion of an explosive mixture, and which prevents the transmission of the explosion to the explosive gas atmosphere surrounding the enclosure. The flameproof enclosure is a generally used type of protection of electrical equipments for use in explosive atmosphere and the most important factors in designing flameproof enclosure are the strength of the enclosure and prevention of flame transmission. In designing the flameproof enclosure, the maximum explosion pressure should be considered. The maximum explosion pressure is subject to changes according to the kinds of gas, gas concentration, ambient temperature, and the inner volume and shape of the enclosure. The ethylene and hydrogen, which are the representative gases in determining the gas classifications have the maximum explosion pressure of around 10 bar but in case of pressure piling due to the specific shape of the enclosure, the maximum explosion pressure can reach several times the initial explosion pressure. But the studies concerning that issue have not been so lively that the importance of the pressure piling has not obtained its due notice and can be missed in designing of explosion protection. In the flameproof enclosure, the ingress of explosive gas atmosphere into it is supposed to occur normally. When the state of flammable gas inside the flameproof enclosure is assumed at atmospheric pressure and normal temperature, the major factors influencing the explosion pressure are the inner volume of the enclosure, inner shape of that and gas concentration. The explosion pressure changes according to the single volume variation at the concentration of H2 and C2H4 of 31 vol.% and 8 vol% each and the pressure piling according to the geometric variations inside the enclosure are experimented. During the pressure piling experiments, it comprises two ways of the geometric variations. One is by partitioning the parallelepiped enclosure of 4,000 cm3 into two spaces with the volume ratio of 25 % : 75 %, 50 % : 50 %, 75 % : 25 % and the other is by the size change of the hole through the partition which was designed for the transmission of an explosion from one space to the other. The size change of the hole is from 0.2 % to 50.2 % in terms of relative area ratio to the area of partition. The results shows the H2 has its maximum explosion pressure at the volume ratio of 75 % : 25 % and hole size of 7.1 % and C2H4 at the volume ratio of 75 % : 25 % and hole size of 3.1 %. The pressure piling occurred within the range of the hole size from 0.8 % to 28.3 % in the case of flameproof enclosure for IIB and from 0.2 % to 12.6 % in the case of the flameproof enclosure for IIC.
more