• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1998.11a
• /
• pp.73-76
• /
• 1998

To use glazing systems protected by automatic sprinklers as fire barriers in building compartmentation, fire endurance tests of these systems have been performed by several research workers. Most of the tests concerned the types of glasses and sprinklers, sprinkler water flow rate, and sprinkler activation time. Horizontal side wall sprinklers and window glazing systems with a vertical center mullion were mainly applied in the tests. In the study, full-scale fire endurance tests were carried out to verify the ability of large glazing systems divided by a horizontal mullion and protected by pendent vertical sprinklers. The result shows that the protrusive length of the horizontal mullion, which is perpendicular to the glass surface, is the main parameter that determines the fire resistance rating of the systems. The mullion obstructs the water flow in the glass.

• Fire Science and Engineering
• /
• v.26 no.6
• /
• pp.85-91
• /
• 2012

To reduce human life and property damage at the fire in a building, it is most critical to control flame spread in the early stage. Fire spread prevention measure generally includes fire resistance performance securing of structure member in the arson zone and use limitation based on combustion performance of finishing material. The latter is most fundamental fire safety design to determine flame spread, but domestic combustion test determines combustion performance by specimen sized fire test method. Thus, there are many restrictions in the determination of combustion performance by composite material such as sandwich panel. Especially, outer finishing material uses a variety of composite material such as dry bit, aluminum composite panel, and metal panel compared to inner finishing material. Therefore, this study would determine vertical fire spread features by a full scaled fire experiment through the test method of ISO 13785-2, an international test standard.

• Fire Science and Engineering
• /
• v.31 no.3
• /
• pp.49-53
• /
• 2017

In the present study, the hydrodynamic force acting on the vertical wall of a portable water storage tank is examined. A Dispersion Relation Preserving (DRP) method, proposed by Jang, is applied for simulating lapping waves and their impact on the wall. A meaningful investigation has been observed, which may be applied to the strength design for the portable water storage tank.

• Fire Science and Engineering
• /
• v.32 no.1
• /
• pp.76-80
• /
• 2018

The present study investigates the hydrodynamic force acting on the vertical wall of a portable water storage tank which has reentrant bottom topology. To numerically simulate the lapping waves in the tank, functional iterative method for the linearized Peregrine's model which numerically simulates the propagating waves over the slowly-sloped bottom topology is introduced. The numerical experiment condition is controlled to adjust the position and the height of the water supplying nozzle. Finally, it is observed that the maximum wave height at the vertical wall and the ratio of hydrodynamic force to hydrostatic one are amplified accordingly. Therefore it must be give attention to this bad effect of amplified hydrodynamic force by the supply method of fire water in order to have the structural stability of the portable water storage tank when it was used on the reentrant bottom topography.

• Journal of the Korean Society of Safety
• /
• v.20 no.1 s.69
• /
• pp.42-48
• /
• 2005

The present study investigates the effect of balcony on external smoke movement of high rise building through the fire tests of the 1/10 reduced model scale using Froude scaling. A hexane pool fire is used to examine the smoke movement for various opening sizes of balcony and temperature distributions are measured by T-type thermocouples. Also, hydrogen bubble technique is applied to visualize the smoke movement near the balcony. Measured temperatures of the closed balcony is 2.5 times higher than those of the open balcony because the external smoke in case of the closed balcony rise along the vertical wall. The maximum vertical temperature of partially closed balcony is similar with fully closed balcony and mean temperature inside of balcony increases as opening size of balcony decreases. The experimental results show that the balcony space plays an important roles in preventing fire propagation and cooling of smoke layer. In order to ensure the fire safety in high rise building design, a series of systematic researches are required to examine the various type of balconies.

• Journal of the Korea Furniture Society
• /
• v.21 no.6
• /
• pp.469-478
• /
• 2010

Fire resistance of new hybrid timber framed wall systems was evaluated in this study. These wall systems are composed of two major structural parts. One part is a heavy timber frame part designed to take charge of whole vertical load using heavy timber post and beam, and the other is an infill wall structure, designed to take charge of whole horizontal load and to provide an established level of fire resistance. A basic concept of this hybrid wall is adopted from a typical furniture structure with frame. A timber post and beam frame is constructed with Japanese Larch solid timber post(180mm by 180mm) and beam(180mm by 240mm). As infill wall systems, two types of walls are applied. One is a typical light timber framed wall with solid blocking and another is a structural insulated panel wall, in which polystyrene insulation is filled between two structural panels to make single structure. For all tested walls, two layers of 12.5mm thick type-X gypsum boards are used on fire exposed side. Prior to tests for hybrid walls, only infill walls are tested without heavy timber frame. All fire resistance tests are carried out in accordance with KS F 2257, and temperatures on several points within wall structure and unexposed wall surface are measured during fire tests. It is considered that the reinforcement of heavy timber frame is significantly efficient for improving the fire resistance of timber framed walls.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2009.04a
• /
• pp.404-409
• /
• 2009

수직벽 화재 예측의 정확성을 확인하기 위하여 화재 시뮬레이션용 전산유체역학 모델인 Fire Dynamics Simulator를 프로필렌 수직벽 화재에 적용하였다. 단위면적당 연소율 $7.0{\sim}29.29g/m^2-s$에 대한 버너 중심에서 측정한 온도분포와 비교한 결과, 최고온도가 낮게 예측되는 것 외에는 실험과 잘 일치하였다. 또 연소율의 증가에 따라 경계측의 두께가 일관되게 증가하였다.

• Fire Science and Engineering
• /
• v.26 no.1
• /
• pp.102-112
• /
• 2012

In this research, configulation of outside sprinkler system the prevention and postponement of vertical diffusion of blaze was studied prior to this study, vertical diffusion protecting sprinkler head has been developed and the sprinkler system was applied with discharge pressure of 0.05 MPa and flow of 60 l/min witch is stated in NFPA13's Exposure Protection Sprinkler Systems. Through the system design, we applied the system to the sample building and we made pertinent system to work manually and automatically linked to a fire alarm system. Also, we conducted a real-size mock up test verify the cooling effect of the outer wall and the postponement effect of the flame.

• Fire Science and Engineering
• /
• v.33 no.1
• /
• pp.50-59
• /
• 2019

Experimental and numerical studies on the fire characteristics according to the distance between the fire source and sidewall under the over-ventilated fire conditions. A 1/3 reduced ISO 9705 room was constructed and spruce wood cribs were used as fuel. Fire Dynamics Simulator (FDS) was used for fire simulations to understand the phenomenon inside the compartment. As a result, the mass loss rate and heat release rate were increased due to the thermal feedback effect of the wall in the compartment fire compared to the open fire. As the distance between the fire source and sidewall was reduced, the major fire characteristics, such as maximum mass loss rate, heat release rate, fire growth rate, temperature, and heat flux, were increased despite the limitations of air entrainment into the flame. In particular, a significant change in these physical quantities was observed for the case of a fire source against the sidewall. In addition, the vertical distribution of temperature was changed considerably due to a change in the flow structure inside the compartment according to the distance between the fire source and sidewall.

• Journal of the Korean Society of Safety
• /
• v.30 no.6
• /
• pp.18-25
• /
• 2015

Computational study of a gravity current prior to the backdraft was conducted using fire dynamic simulator (FDS). Various initial conditions of mixture compositions and compartment temperature as well as four opening geometries (Horizontal, Door, Vertical, and Full opening) were considered to figure out their effects on the gravity current. The density difference ratio (${\beta}$) between inside and outside of compartment, the gravity current time ($t_{grav}$) and velocity ($v_{grav}$), and non-dimensional velocity ($v^*$) were introduced to quantify the flow characteristics of the gravity current. Overall fluid structure of the gravity current at the fixed opening geometry showed similar development process for different ${\beta}$ conditions. However, $t_{grav}$ for entering air to reach the opposed wall to the opening geometry increased with ${\beta}$. Door, Vertical, and Horizontal openings where openings are attached on the ground showed similar development process of the gravity current except for Horizontal opening, which located on the middle of the opening wall. The magnitude of $v_{grav}$ at fixed ${\beta}$ was, from largest to smallest, Full > Vertical > Door > Horizontal, but it depended on both the size and location of the opening. On the other hand, $v^*$ was found to be independent to ${\beta}$, and only depended on the geometry of the opening.