• Journal of the Korean Society of Industry Convergence
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• v.22 no.5
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• pp.553-559
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• 2019

Various types of nozzles have been used to cope with fire in ships. However, in Korea, precise nozzles that perform fine spraying function are required for fire fighting in case of fire in a ship, and most of these nozzles depend on imports. Therefore, in this study, we developed various types of nozzles to develop the water spray nozzle for evolving fire in the engine room of the ship, and developed an optimal nozzle through flow analysis and fire test. For this purpose, we selected the materials that can satisfy the characteristics of existing nozzle materials and developed the design technology and processing technology in the nozzle considering fluid flow to achieve optimal water spraying performance. In order to develop an optimal nozzle, the flow through the finite element analysis was first analyzed and the nozzle was manufactured. As a result of flow analysis of the developed nozzle, the maximum velocity at the outlets of four holes at 0.3 MPa was about 3m/s and about 0.15 MPa. In addition, when the pressure at the inlet was 1.8 MPa, it showed the outlet speed of about 18m/s and a pressure of 1.2 MPa.

• Journal of the Korea Safety Management & Science
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• v.24 no.4
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• pp.117-124
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• 2022

This study collected powder extinguishers with 6-10 years of elapsed life from January 2012 to January 2017 in market, factory, and apartment areas to experiment with changes in fineness and to examine the characteristics of extinguishing power. First, in the case of ABC powder, 98.3 wt% of the 8-year market area and 98.6 wt% of the 10-year apartment complex were found to be inappropriate in the first, second, and third arithmetic average analysis of the powder extinguisher from 6 to 10 years. That is, the fine distribution and size of the powder extinguishing agent particles should be managed within an appropriate range. It is analyzed that the powder fire extinguisher may experience a change in the fineness of the powder depending on the external environment exposure, placement, management status, and age of use, resulting in a decrease in digestive power or inability to radiate. Second, the fire extinguisher cannot be used in the initial fire suppression depending on the place of deployment, the environment of deployment, the progress of the number of years of use, and maintenance, so it is necessary to strengthen the device that enables fire extinguisher maintenance and inspection. Third, in the manufacturing process, the charging method should also be reviewed in consideration of the conditions of the workplace, the humid season, and the rainy environment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.301-302
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• 2023

In this study, we aimed to identify changes in fire resistance according to the type of sleeves used for pipe penetrations and to examine their accreditation of fire resistance performance and use them as basic data. The test results of fire resistance according to the type of sleeve used in non-metallic pipe facilities showed that the temperature on the support side was higher for sleeves with higher thermal conductivity. For the temperature on the surface of the pipes, in the case of galvanized steel plates, steel pipes, and structures without sleeves, the highest temperature was observed after the expansion of the firestop material for 46 to 53 minutes and then decreased. PVC sleeves showed a steady increase in temperature until 53 minutes, after which the temperature did not increase further. In addition, for non-metallic pipes, the effect of the type of sleeve on fire resistance is considered to be insignificant because the lower part (heating direction of the furnace) under the support structure is cut off to block the heat during the two-hour fire resistance test.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.473-480
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• 2009

The 180 minutes fire test based on the standard curve of ISO-834 were conducted on three RC column specimens with different constant axial loading ratios to evaluate the fire performance of fiber cocktail (polypropylene+steel fiber) reinforced high strength concrete column. The columns were tested under three loading levels as 40%, 50%, and 61% of the design load. No explosive spalling has been observed and the original color of specimen surface has been changed to light pinkish grey. The maximum axial displacements of three specimens were 1.5~2.2 mm. There was no reduction in load bearing capacity of each specimen exposed to fire and no effect were observed on the fire performance within 61% of the design load. The tendencies of the results with loading, such as the temperature distribution of in concrete and the changes in temperature rise due to the water vaporization in concrete, are very similar to those without loading. The final temperatures of steel rebar after 180 minutes of fire test resulted in 491.4${^{\circ}C}$ for corner rebar, 329.0${^{\circ}C}$ for center rebar, and 409.8${^{\circ}C}$ for total mean of steel rebar. The difference of mean temperature between corner and center rebar was 153.7${^{\circ}C}$ㅍ. The tendency of temperature rise in concrete and steel rebar changed after 30~50 minutes from the starting time of the fire test because the heat energy influx into corner rebar is larger than that into center rebar. The cause of decrease in temperature rise was due to the water vaporization in concrete, the lower temperature gradient of the concrete with steel and polypropylene fiber cocktails, the moisture movement toward steel rebars and the moisture clogging.

• Fire Protection Technology
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• s.16
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• pp.5-12
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• 1994

• Fire Protection Technology
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• s.17
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• pp.19-23
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• 1994

This is a interpretation paper to introduce for the flammability test methods & requirements for electric cables specified in Japanese standards.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2000.04a
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• pp.75-79
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• 2000

• Fire Protection Technology
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• s.55
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• pp.7-12
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• 2013

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.11a
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• pp.182-187
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• 2007

• Fire Science and Engineering
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• v.5 no.1
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• pp.23-28
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• 1991

This paper is concerned with the numerical analysis of the temperature of steel columns when they are exposed to flame of a fire temperature curve in order to test resistivity against the fire. In this stuer a 2-dimensional heat conduction FDM was developed to predict the temperature dustribution of steel column under various construction conditions. A proposal to estimate the influence of free water content in the insulation also made.