Hyun-Joon Shin

A Study of Effect of the Radiative Heat Flux on the Evacuation of Agents

Recently, the safety assessments with using the various evacuation programs are performed for improving the performance of fire and evacuation safety in the building. Generally, the evacuation programs can simulate the human behavior in fire situation by applying the variation of the movement speed and Fractional Effective Dose (FED) index in the smoke. However, if the simulation is performed without optional setting around the fire, the agents do not avoid the fire and they move through the fire. Therefore in this study, we define the radiative repulsion force which exists between the fire and the agents. Moreover, we modify the Helbing`s movement model by adding the radiative repulsion force. As a result of the modified movement model, all agents move around the fire and they do not enter the upper bound area of radiative heat flux, . From these results, we verified the reliability of the modified movement model.

Study on Suggestion of Smoke-proof System Using a Restroom for a Refuge Space

In restroom on high-rise building, exhaust system comprising the blower and duct is installed to discharge the odor and the water is suppled. Thus the restroom with fire and flame protection system may be used as refuge area in a fire situation. The study presents the smoke-proof system which operates such that the exhaust system to discharge the odor is converted to air supply system and appropriate pressure difference between the restroom and the accommodation is maintained. Also real-scale test facilities of smoke-proof system for refuge space using a restroom are installed on 5-story smoke control test building and experiments for evaluating the operational performance of smoke-proof system are carried out.

Nano-Soot Particle Formation in Ethene/Air Inverse Diffusion Flame

Experimental measurements of flame structure and soot characteristics were performed fur ethene inverse diffusion flames (IDF). IDF has been considered as the excellent flow field to study the incipient soot because soot particle do not experience the oxidation process. In this study, LIF image clarified the reaction zone of IDF with OH signal and PAH distribution. laser light scattering technique also identified the being of soot particle. To address the degree of soot maturing, C/H ratio and morphology of soot sample were investigated. From these measurements, the effect of flow residence time and temperature on soot inception could be suggested, and more details on soot characteristic in the IDF was determined according to fuel dilution and flame condition. The fuel dilution results in a decrease of temperature and enhancement of residence time, but the critical dilution mole fraction is existed for temperature not to effect on soot growth. Also, the soot inception evolved on the specific temperature and its morphology are independent of the fuel dilution ratio of fuel.

Development of Smoke Control System Ensuring Safe Evacuation Through Stairwell for High-Rise Building in Korea

In general, the pressure differential smoke control system has been used as a smoke control system on the emergency stairs of high-rise buildings, but it can fail to achieve the purpose of pressure differential system due to high possibility of overpressure between the lobby and the accommodation or pressure drop in the lobby in case the leakage and supplementary air flow is supplied at the same time through one air supply path. In connection with improvement of this problem, we suggested device configuration and methods to conduct supply of leakage and supplementary air flow through different flow passages, thereby providing safe evacuation environment in case of a fire in high-rise buildings.