• Journal of the Korean Society of Safety
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• v.20 no.2 s.70
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• pp.11-17
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• 2005

Rotational motion in the atmosphere around a fire may have a profound influence on the fire plume. This process underlies the occurrence of fire whirls. Fire whirls are rare but highly destructive phenomenon which were observed in a large forest, urban and building fires. The present study aims to investigate of the effect of rotation Strength on the fire whirl characteristics expeimentally. Experiments are performed for various sizes of fire source with different rotation strength. From the experimental observations, it is noted that the mean centerline temperature is gradually increased and mean radial temperature is decreased as increases rotation strength. The characteristic mean flame height of fire based on the visible observation is increased as increases of dimensionless swirl parameter, $\Omega/\alpha$, represented by swirl induced motion to buoyancy driven motion.

• Fire Science and Engineering
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• v.22 no.5
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• pp.55-60
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• 2008

In this study, we conducted an FDS numerical simulation for the purpose of carrying out a basic assessment of the usefulness of the water spray for fire extinguishing. We analyzed the effect of securing the stability in temperature and smoke density in case of fire according to fire intensities (20MW, 50MW) and changes in wind speed. When there was no wind speed in tunnels, it was effective in securing the safety of people because the cooling effect of the water spray system had an excellent effect on reducing temperatures and smoke densities there. The higher a fire intensity is, the less effect it has on reducing smoke flows. When an air current exists in tunnels, its cooling effect disturbs the smoke stratification and lowers the visibility degree during evacuation. Therefore, the water spray for fire extinguishing should be put into action only after people take shelter during fire.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.43-53
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• 2020

The purpose of this study is to reduce the anxiety factors of fires by following evacuation tips in case of fire in an apartment household. This study analyzed the moderating effects of the control offices' competence in control on safety awareness and fire response. The study results were as follows. First, the residents and control staff's safety awareness had a positive effect on the fire response performance. This indicates that the higher the residents and control staff's safety awareness level, the higher the fire responsive performance. Second, the higher the control offices' control competence level, the better the apartment residents and control staff's safety awareness had a positive effect on the fire response performance. These results indicate that the higher the control office heads' leadership, the higher the apartment residents' housing satisfaction and that the more communicative the control office heads' attitude toward the residents, the better their attitude had a positive effect on the fire response performance. Lastly, the control offices' control competence was analyzed to have a moderating effects on the effect of the apartment residents and control staff's safety awareness level on the fire response performance. These results showed that the change in the model's R² value showed an increasing trend in stages as the value increased more in the stage 2 than the stage 1 and even more in the stage 3 with the interaction terms of the moderating variables added. For this reason, the control offices' control competence which was a moderating variable was analyzed to have a moderating effect on the effect of residents and control staff's safety awareness level on the fire response performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.184-185
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• 2013

Concrete filled steel Tube(CFT) columns have great strength but also fire resistance performance due to the heat storage effect of concrete. In this research, we focus on the fire performance of CFT using 100 MPa concrete without fire protection. We use steel fiber and nylon fiber for fire resistance. We perform the fire test of CFT specimen with loading 200, 300 and 400 ton. To investigate the effect of loading to fire resistance, we compare the fire resistance time according to the loading.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.305-310
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• 1997

There are many parameters in prediction of forest fire spread. The variables such as fuel moisture, fuel loading, wind velocity, wind direction, relative humidity, slope, and solar aspect have important effects on fire. Particularly, wind and slope factors are considered to be the most important parameters in propagation of forest fire. Generally, slope effect cause different wind distribution in mountain area. However, this effect is disregarded in complex geometry. In this paper, wind is estimated by applying computational fluid dynamics to the forest geometry. Wind velocity data is obtained by using CFD code with Newtonian model and slope is calculated with geometrical data. These data are applied fer 2-dimentional forest fire spreading algorithm with Korean ROS(Rate Of Spread). Finally, the comparison between the simulation and the real forest fire is made. The algorithm spread of forest fire will help fire fighter to get the basic data far fire suppression and the prediction to behavior of forest fire.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.2
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• pp.349-352
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• 2015

This paper estimates electrical fire damage cost-effect to analyze electrical safety efficiency by applying a cost-benefit analysis method for analyzing the efficiency of a business public interest. Electrical fire loss statistics data was presented as direct costs and casualties, including deaths due to an electrical fire, this paper adds overhead "Incidental Cost of Accidents to the Employer" by W. H. Heinrich was applied to estimate the cost of economic loss. Also wounded, including the loss of human deaths by referring to the car accident insurance claims costs and human development estimated the losses caused by an electrical fire. And to perform a cost-benefit analysis of the electrical safety as a result of future work. In this paper, the economic effect of the electric field of safety and public interest work to systematically presented.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.2
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• pp.45-49
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• 2015

This paper presents a quantitative analysis method to quantitatively indicate a electrical fire preventive effect of safety inspection for electrical facilities for general use. Logic model was developed based on whether enforcement of safety inspection for electrical facilities, and then the developed analysis model was converted to hydraulic model by using mathematical logic. The electrical fire preventive effect of safety inspection for electrical facilities was quantitatively calculated by applying electrical safety inspection results and fire statistics for five years to the developed hydraulic model. The results show that electrical fire preventive effects of 5,542 cases on annual average for five years.

• Fire Science and Engineering
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• v.14 no.3
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• pp.6-12
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• 2000

This paper describes the smoke movement of a fire field model based on a self-developed SMEP(Smoke Movement Estimating Program) code to the simulation of fire induced flows in the two types of compartment space containing the radiation effect under smoke movement in room fire. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon $ turbulence model with buoyancy term. Also it solves the radiation equation using the discrete ordinates method. The result of the calculated smoke temperature containing radiation effect has shown reasonable agreement compared with the experimental data. On the other hand, a difference of a lot was found between the temperature predicted by the SMEP with only convection effect and obtained by the experimental result. This seems to come from the radiation effect of $H_2$O and $CO_2$ gas under smoke productions. Thus, the consideration of the radiation effect under smoke in fire may be necessary in order to produce more realistic result.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.363-370
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• 2008

The present study has been performed to investigate the effect of statistical number of droplets on the simulation of the sprinkler spray using fire field model. In order to simulate the sprinkler spray characteristics, the present study uses NIST Fire Dynamics Simulator version 5.2. A group of Lagrangian particle with similar droplet characteristics, such as diameter, velocity, temperature and so on, is represented by parcel concept to decrease the total number of droplets tracked in the simulation. The present study introduces a new parameter to represent the ratio between real number of droplets and computational parcels. The dependency of the number of parcels on the fire suppression characteristics and spray patterns is quantitatively examined for different ratio between the real number of droplets and computational parcels.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.153-156
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• 2008

Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area was studied in this work. To investigate the effect of thinning slash in forest fire, Gangneung-si Wangsan-myeon, Ulgin-gun Wonnam-Myeon, Samchok-si Gagok-Myeon, in which forest fire broke out, were selected. As a result that investigated forest fire danger ratio between thinning slash and non-thinning slash, leeward scorching ratio(36%), crown damage ratio(29%), mortality of branch at the former are higher than those at the latter, leeward scorching ratio of tree, where thinning slash is around, is 10%-20% higher than that of independent tree. So I estimate that thinning slash has a some effect on the intensity of forest fire. And the result to investigate damage of forest fire according to tree species shows that leeward scorching ratio of conifer is 5% higher than that of non-conifer, and mortality of branch of the former is 19% higher than that of the latter. It is considered that forest fire may affect directly to a tree trunk if it diffuse to piled thinning tree because there was no space between thinning trees and trees. Furthermore, it was found that re-ignition had a chance to occur due to lots of piled thinning trees.