• Fire Science and Engineering
• /
• v.16 no.2
• /
• pp.38-42
• /
• 2002

This experiment is to understand a characteristics of smoke layer formation affected periodicity of fire plumes. The ON-OFF jet was used to constitute the oscillating flow, which was formed by a mixture of nitrogen gas with kerosene particles. The instantaneous images was obtained by digital video camera using laser sheet technique. The results were confirmed that the smoke layer in the near fire source comprise vortices which are formed by impingement from the periodicity of fire plume. The periodic impinging of plumes were thickened the smoke layer and produced the back-flow.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2008.04a
• /
• pp.15-18
• /
• 2008

A study on the fire and smoke behavior on experiments and analysis through STAR-CD in using about behavior analysis of the smoke. Kerosene of 3L in using on the experimental garden of 30cm in diameter same applies to heat release rate(HRR), buoyant force by Plume can be calculated at a rate of 1m/s. The result of experiment in average of velocity were 0.29m/s, and interpreted result were 0.28m/s. Besides, it is proved by interpreted that behavior of smoke movement can be not observed in the experiment. After smoke is Plume increased, ceiling-jet in formation being descend in smoke layer will be more thick smoke layer, and then vertical wall is collapsed in formation of wall-jet being descend. It is defined that smoke layer is more thick through descending course in wall-jet and ceiling-jet.

• Fire Science and Engineering
• /
• v.24 no.6
• /
• pp.20-27
• /
• 2010

In smoke control systems the amount of air supply is almost the same as that of smoke exhaust. This study analyzed the effect of supply air velocity on the smoke exhaust behavior using FDS tool. The results showed that fire plume can be disheveled by the rapid air velocities developed when the air supply inlet is located near the fire plume. Disheveled smoke caused the rapid descent of smoke layer level and the reduced visibility. To increase the efficiency of smoke exhaust systems supply air inlet should be located sufficiently far from the location of the fire plume.

• Journal of Korean Society of Disaster and Security
• /
• v.12 no.2
• /
• pp.47-56
• /
• 2019

Recently, in order to overcome the difficulty of entering a fire source due to the occurrence of a large amount of smoke in the event of a fire in a parking lot, it has used that a method of discharge smoke using air supply, exhaust fans and jet fans installed for ventilation of parking lots. In this study, the variation of flow in the smoke layer was observed using CCTV under two conditions, in which only the air supply fan operates and the manned fan operates together, and the temperature around the plume was compared to Albert eq. to assess its suitability as a parking lot ventilation performance evaluation method. As a result, it was found that the smoke layer could be disturbed if the Jet Fan was operated at the same time, which could lead to the possibility of an initial evacuation disturbance. However, the additional operation of the Jet Fan has been confirmed by the observation CCTV that the emission performance is improved, which is believed to help conduct the suppression operation. The temperature around the plume was measured and compared to Alpert eq, and was analyzed to be about $2^{\circ}C$ lower at the center axis of the plume and $9.0^{\circ}C$ higher at 8 m in the direction of the discharge of smoke. The results of temperature measurements around the plume were lower than the maximum temperature expected in AS 4391 and did not exceed the expected temperature risk caused by the experiment. As with these results, the temperature risk from the progression of hot smoke tests is foreseeable, so it will be available as one of the general evaluation methods for assessing smoke control performance in a parking lot without relevant criteria.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2008.05a
• /
• pp.11-14
• /
• 2008

A study on the fire and smoke behavior on experiments and analysis through STAR-CD in using about behavior analysis of the smoke. Kerosene of 3L in using on the experimental garden of 30cm in diameter same applies to heat release rate(HRR), buoyant force by Plume can be calculated at a rate of 1m/s. The result of experiment in average of velocity were 0.29m/s, and interpreted result were 0.28m/s. Besides, it is proved by interpreted that behavior of smoke movement can be not observed in the experiment. After smoke is Plume increased, ceiling-jet in formation being descend in smoke layer will be more thick smoke layer, and then vertical wall is collapsed in formation of wall-jet being descend. It is defined that smoke layer is more thick through descending course in wall-jet and ceiling-jet.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1996.11a
• /
• pp.5-9
• /
• 1996

In foreign country such as U.S.A and Japan, considerable research has been done regarding the spread of smoke in room of fire involvement by using computer. But, in our country it has not been. So, this paper presents a detailed qualitative description of phenomena which occures during typical fire scenarios through numerical analysis. This research, in the view of field model, is focused on finding out the smoke movement and temperature distribution. And it is planned to analyze governing equation including smoke diffusion equation by numerical analysis with finite volume method and non-staggered grid system. The SIMPLE method for pressure-velocity couple and power-law scheme for convection terms are used. It shows that a plume is formed, hot plume is formed, hot plume gases impinge on the ceiling and they spread across it. then, it eventually reaches the bounding walls of the enclosure. It takes 60s for smoke to fill the enclosure.

• Fire Science and Engineering
• /
• v.10 no.3
• /
• pp.10-18
• /
• 1996

In foreign country such as USA and Japan, considerable research has been done regarding the spread of smoke in room of fire involvement by using computer. but, in our country it has not been, so, this paper presents a detailed qualitative description of phenomena which occure during typical fire scenarios through numberical analysis. The governing equations are solved by using FVM method with non-staggered grid. The SIMPLE method for pressure-velocity couple and power-law scheme for convention terms are used. It shows that a plume is formed, hot plume gases impinge on the ceiling and they spread across it. then, it eventually reaches the bounding walls of the enclosure. It takes 20s for smoke to fill the enclosure.

• Fire Science and Engineering
• /
• v.14 no.2
• /
• pp.21-32
• /
• 2000

In this study, reduced-scale experiments as the alternative to a real-scale fire test were conducted to understand fire properties in tunnel, and their results were compared with those of numerical simulation. The 1/20 scale experiments were conducted under the Froude scaling since smoke movement in tunnel is governed by buoyancy farce. A numerical simulations were on performed 3D unstructured meshes with PISO algorithm and buoyant plume models. Results showed that data was in reasonable agreement with the numerical data of smoke velocity, temperature distribution, and clear height.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.491-492
• /
• 2003

The large amount of smoke produced near Lake Baikal was transported to Northeast Asia with high AOT (Aerosol Optical Thickness) as seen in satellite images. Aerosol retrieval using a separation technique was applied to MODIS (Moderate Imaging Spectroradiometer) and SeaWiFS (Sea-viewing Wide Field-of-view Sensor) data observed during 14-22 May 2003. Large AOT, 2.0~5.0 was observed on 20 May 2003 over Korea due to the influence of the long range transport of smoke aerosol plume from the Russian fires, resulting in high PM10 concentration was observed at the surface.

• Medical Lasers
• /
• v.8 no.2
• /
• pp.43-49
• /
• 2019

The plume produced by vaporizing tissue with a laser contains a variety of contaminants called laser-generated air pollutants (LGACs). LGACs consist of a mixture of toxic gas components, biomicroparticles, dead and living cells, and viruses. Toxic odors and thick smoke from surgical incisions and the coagulation of tissues can irritate eyes and airways, as well as cause bronchial and pulmonary congestion. Because of the potential risk of the smoke, it is advisable to appropriately remove it from the surgical site. We recommend using a smoke evacuator to remove the smoke. Suction nozzles should be placed as close as possible to the surgical site in a range of 2 cm or less. In-line filters should be used between the inlet and outlet of the surgical site. All air filtration devices should be capable of removing particles below 0.1 microns in size. The filter pack should be handled according to infection control procedures in the operating room. The laser mask can be an auxiliary protective device if it is properly worn. Some smoke inhaled under the nose wrap or over the side of the mask will not be filtered. As in electrosurgical operations, a suitable mask should be worn while smoke is present.