• Journal of the Korean Society of Safety
• /
• v.13 no.4
• /
• pp.59-70
• /
• 1998

In this study, response time index(RTI) of standard and quick response type sprinkler head are measured and compared through ramp and plunge test in heated wind tunnel. Also discharge rate and water distribution, actual delivered density(ADD), fire test with wood cribs are performed to compare the fire suppression capability and the operation time and temperature between standard and quick response type sprinkler head.

• Journal of the Korean Society of Safety
• /
• v.32 no.4
• /
• pp.16-21
• /
• 2017

The sprinkler system is a basic fire extinguishing system that uses water as an extinguishing agent. In order to evaluate the fire extinguishing performance of the sprinkler system, information such as the discharge angle, discharge speed, discharge pressure, flow rate, and water droplet size of the installed head are required. However, there is a lack of research on droplets size compared to other requirements. In this study, to evaluate the extinguishing characteristics of sprinkler system, the droplet size distribution was measured for various types of sprinkler heads actually used. The size of the droplet was measured using laser diffraction method. The 50% cumulative volume distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the Rosin-Rammler index value are presented. As a result of the fire simulation with FDS, it was confirmed that the performance difference occurs according to the water droplet size distribution even when the same amount of water is used. Therefore, the extinguishing performance of the sprinkler system should be evaluated considering the droplet size distribution according to the sprinkler head type.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.1319-1320
• /
• 2010

• Fire Science and Engineering
• /
• v.18 no.3
• /
• pp.1-8
• /
• 2004

As a predominant active fire suppression method, closed-type sprinkler systems are used for the purpose of fire control and suppression at the nuclear power plants as well as the industrial facilities. It goes without saying that the proper selection of the system guarantees the adequate actuation of the thermal device. Consequently, the appropriate evaluation should be executed for the thermal behavior with the theoretical and empirical approach. For this purpose, the comparison of activation time for the fusible-link type sprinkler head with the simplified fire case and t-square fire growth case was evaluated. At this paper, the comparison output was presented with the tendency of thermal behavior. In addition, we issued some technical comments for the most appropriate equation in case of the estimation of the sprinkler head activation time. We also raised some idea that should be incorporated for the usage of the t-square equation for the realistic application in the field of the performance-base fire protection approach.

• Journal of the Society of Disaster Information
• /
• v.15 no.1
• /
• pp.98-108
• /
• 2019

Purpose: The purpose of this study is to test the sprinkler performance to protect the wall and ceiling joints of the sandwich panel warehouse in case of fire. Method: Based on the field surveys, test was setup and combustibles were prepared. The sprinkler discharge tests were performed at the corner of the wall and right under the sprinkler head. Results: It has been found that operation of the K-80 closed sprinkler head prevents the ignition of the sandwich panel and therefore no damage to the joints of sandwich panels. To prevent skipping phenomenon, it is necessary to install the sprinkler head from the corner of the wall and to keep a minimum distance of 2.4m and a maximum distance of 3m. Conclution: A Standard Operation Procedure should be prepared to suppress and rescue of fire brigade for a sandwich panel warehouse protected by perimeter sprinklers preventing a ignition of core materials and control fire.

• Fire Science and Engineering
• /
• v.30 no.6
• /
• pp.111-117
• /
• 2016

The present study examined the free surface flow of a liquid sheet near a sprinkler head using a Computational Fluid Dynamics (CFD) model and considered the feasibility of the empirical model for predicting the initial spray characteristics of the sprinkler head through a comparison of the CFD results. The CFD calculation for a simplified sprinkler geometry considering the nozzle and deflector were performed using the commercially available CFD package, CFX 14.0 with the standard $k-{\varepsilon}$ turbulence model and theVolume of Fluid (VOF) method. The predicted velocity of the empirical model at the edge of deflector were in good agreement with that of the CFD model for the flat plate region but there was a certain discrepancy between the two models for the complex geometry region. The mean droplet diameter predicted by the empirical model differed significantly from the measured value of the real sprinkler head. On the other hand, the empirical model can be used to understand the mechanism of droplet formation near the sprinkler head and predict the initial spray characteristics for cases without experimental data.

• Fire Science and Engineering
• /
• v.30 no.5
• /
• pp.26-35
• /
• 2016

Sprinkler installations shall be operated at normal operating temperature of the atmosphere as a fire sprinkler head in any facility to control and extinguish the fire when the fire initially. Recently, however, some flush type quick response automatic sprinkler heads in slow fire place is a problem that can not be normal operation are raised. In this paper, by using the experimental model of the Apartment house of Commons and Cabinet burner size bedrooms fire conditions to form a slow growth rate and can supply more than 0.2 MPa pressure is the minimum pressure that can be applied inside the pipe in the field experiment was conducted. In the majority of experiments lush type quick response automatic sprinkler heads which is used in the country it was confirmed to be incompletely opened as the Cold Soldering occur. This phenomenon is likely to fail early fire suppression and control because they can cause the spread of fire and casualties needed to complement domestic product testing and type approval standards through additional research.

• Fire Science and Engineering
• /
• v.31 no.3
• /
• pp.54-62
• /
• 2017

The aim of this study is to find out the water spray features of in-rack sprinklers for rack storage. This study conducted cold water flow test, measurement of spray angle and densities by angles for sprinkler head manufactured by a Korean company and a U.S. company. Korean sprinkler head had a wide angle of water spary. The water spray angle of a U.S. sprinkler head was narrow compared to the Korean sprinkler. In comparison of the Korean head with U.S. head of the same K80, the Korean head can send water to parts that are difficult to directly spray, but the spraying density by angle was low. U.S. head can send more water than Korean head at a narrow angle. In conclusion, for flammable materials placed in two or more rows in a rack storage, a zigzag arrangement with face sprinklers will be effective.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.1
• /
• pp.461-468
• /
• 2022

This study is focused on the ignition of ceiling insulation depending on working condition of Sprinkler head in underground parking lot fire. When temperature changes of same point were measured depending on sprinkler's working condition, in Scenario 1, inner temperature at border of spray applied material(SP-2) of ceiling part near the fire and ceiling insulation(blowing polystyrene) was 658.27℃ and its which inner maximum temperature is higher than 427℃ which is the ignition point of ceiling insulation(blowing polistyrene), so it was observed that flame is ignited on the ceiling insulation and spread fire. In scenario 2, Inner fire temperature at border of spray applied material(SP-2) and ceiling insulation(blowing polystyrene) near the fire was 53.10℃ and it was lower than ignition point so it was observed that flame was not ignated on the ceiling insulation. As a result, it was foreseen that possibility of ignition on the ceiling insulation depending on working condition of sprinkler.

• Journal of the Society of Disaster Information
• /
• v.16 no.2
• /
• pp.237-247
• /
• 2020

Purpose: This study aims to draw the problems and improvements of NFSC 103 sprinkler head discharge obstruction prevention standard to increase the fire extinguishing performance of sprinkler system in order to contribute to the protection of people's lives and property in the event of a fire. Method: NFSC 103 was compared to NFPA 13 which is the latest 2019 version in U.S in terms of sprinkler head discharge obstruction prevention. Results: This study found that NFSC 103 doesn't define even the basic concept of sprinkler discharge obstruction. And NFSC 103 doesn't have detailed standard for side wall sprinkler head discharge obstruction prevention as well as the "height" criteria of the "three times" separation rule. Conclusion: NFSC 103 needs a lot of supplements and improvements such as the addition of definition for water discharge obstructions, the adoption of sidewall sprinkler heads standard for preventing water discharge obstructions and the additional establishment of the "three times rule" considering the "height" of obstacles to promote the advance of fire safety standard equal or above fire fighting advanced country and increase the reliability for the suppression performance of sprinkler system.