• 한국연소학회:학술대회논문집
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• 1998.10a
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• pp.37-46
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• 1998

In this experiments, smoke filling behaviors in a large space were investigated. Also, it found that the smoke filling time can be predicted with a simplified zone model. Thermocouples were used to measure the temperature of the hot gases layer and also later to determine the smoke layer depth. Height markers were also hung from the roof so that observers could visibly assess the smoke layer depth.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1998.11a
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• pp.53-60
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• 1998

In this study, smoke filling behaviors in a large space were investigated. For experimental study, thermocouples were used to measure the temperature of the hot gases layer and also to determine the smoke layer depth. Height markers were also hung from the roof so that observers could visibly assess the smoke layer depth. Ethanol was used as fuel. The smoke filling times were predicted with zone model and field model and numerical results were compared with experimental data. Good results were obtained.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.456-463
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• 1997

Atrium buildings are commonly found in Hong Kong since 1980. Those spaces are usually crowded with people and so fire protection systems have to be installed for providing a safe environment. Smoke control system was identified to be important but no clear design guidelines are available because the smoke filling process was not well-understood. In this paper., Computational Fluid Dynamics(CFD) or fire field model is applied to study the smoke filling pattern in atrium. Two common cases on smoke spreading out from a shop adjacent to the atrium; and with a fire located at the atrium floor itself were considered. Simulations with a modified form of the CFD package TEAM were performed. Application of the predicted results Is illustrated.

• Fire Science and Engineering
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• v.11 no.3
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• pp.3-14
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• 1997

An experimental investigation of smoke spread in a corridor is made using thermocouples and visualization technique with a laser beam sheet. A speed of smoke front under a ceiling is measured by thermocouple trees. Visualization of the ceiling jet formation and of smoke filling process is carried out to observe lowering of the smoke layer. From the results, a large-scale convective motion the corridor plays dominant roles for smoke spread from visualized photos together with temperature records. A circulating motion of fluid transports some smokes to some regions where its momentum is effective. It is therefore showed that the conventional concept of lowering smoke with two-layer zone model has some restrictions for the corridor because the lowering of smoke layer has been thought to be mass transport due to relatively small scale motion such as decrease of buoyancy, mass diffusion and momentum exchange.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.3
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• pp.117-128
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• 2002

This paper describes the smoke filling process of a fire field model based on a self-deve-loped SMEP (Smoke Movement Estimating Program) code to the simulation of fire induced flows in the two types of atrium space containing a ceiling heat flux. 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 production term. Also it solves the radiation equation using the discrete ordinates method. Compressibility is assumed and the perfect gas law is used. Comparison of the calculated upper-layer average tempera-ture and smoke layer clear height with the zone models has shown reasonable agreement. The zone models used are the CFAST and the NBTC one-room. For atrium fires with ceiling glass the ceiling heat flux by solar heat causes a high smoke temperature near the ceiling. However, it has no effect on the smoke movement such as the smoke layer clear heights that are important in fire safety. In conclusion, the smoke layer clear heights that are important in evacuation activity except the early of a fire were not as sensitive as the smoke layer tem-perature to the nature of ceiling heat flux condition. Thus, a fire sensor in atrium with ceiling glass has to consider these phenomena.

• Fire Science and Engineering
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• v.15 no.1
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• pp.7-15
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• 2001

This paper describes the smoke filling process of a fire field model based on a self-developed SMEP (Smoke Movement Estimating Program) codo to the simulation of fire induced flows in the atrium space (SIVANS atrium at Japan) containing smoke radiation effect. 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 a better prediction than the result calculated by only convection effect in comparison with the experimental data. 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 should be necessary in order to get more realistic result. Also the numerical results indicated that the smoke layer is developing at a rate of about 0.1 m/s. It would take about 450 seconds after starting the ultra fast fire of 560 kW that the smoke layer move down to 1.5m above the escape level.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.139-148
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• 1995

This study was carried out to investigate the effects of super heated steam on the physical and chemical changes of burley cut tobacco. Total sugar, total alkaloid, ether extracts, crude ash, total nitrogen and pH for leaf chemical constituents were analyzed. Filling power and fineness index for physical properties, and carbonyl compounds, phenol compounds, amonia, pH, hydrogen cyanide nicotine, carbon monoxide, total volatile base and tar for smoke components were also analyzed. The cut tobacco treated with super heated steam showed significant decrease in total sugar and total alkaloid. The filling power of the sample treated with the super heated steam system was increased abruptly when heated at over 250℃. The fineness index showed similar tendency to that of common toast method. Super heated steam treatment slightly decreased carbonyl compounds, phenol compounds, hydrogen cyanide, nicotine, carbon monoxide and tar in the tobacco. Especially the decrease of ammonia was the most remarkable. The pH of smoke was a little different compared with that in the common toast. The sensory test results showed that, compared to the common conveyer moving system, the tobacco treated with super heated steam system brought out more roasted flavor, lowered impact, irritation, and sting, further improved aftertaste, and lowered bitterness. The super heated steam treatment method used in the studies is expected to give better filling power, mild taste and toasted odor of tobacco than that of the common method for toast treatment. Key words : burley tobacco, super heated steam, expansion, toast.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.10
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• pp.687-698
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• 2011

In this study, it was analyzed by a numerical analysis that plan/design considerations for ensuring the spectator safety of large arena audiences in a fire emergency evacuation plan. The latest issue, the 'performance-based design', fire and evacuation plan is important. But nowadays 'Specification-based design' is in common. In evacuation simulation, congestion of exit and aisle is ignored because only evacuation time of large-space is mainly analyzed. In smoke flow,'smoke filling effect' tends to be overrated. From now on, when design a field house, it is needed not 'smoke filling effect' and 'large-space evacuation' analysis, but analyzing 'whole building evacuation time' for ensuring fire evacuation safety of spectator.

• Applied Biological Chemistry
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• v.21 no.2
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• pp.131-136
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• 1978

The effects of liquid sugar and sucrose on several characteristic of tobacco leaves, there combustibility and harmful compound in smoke were examined. results obtained were as follows. 1) Nicotine and total nitrogen content of tobacco leaves were reduced by sugars added to tobacco. 2) Nicotine and tar transfered to smoke were reduced by 4% sugars added to burley tobacco but not reduced by sugars added to hicks. 3) pH of smoke was reduced by sugars added but pH of tobacco shreds not reduced by sugars added. 4) The filling capacity and combustibility (S. B. R.) of tobacco shreds were increased by sugars treated. 5) Nitrogen oxides transfered to smoke was reduce by sugars treated but phenols transfered was not reduce by sugar treated. 6) The capacities of moisture absorption and retention was increased by sugars treated.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.217-222
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• 2015

There has been increased amount of atmospheric pollutants including NOx and SOx which cause acid rain and photochemical smog as a result of increased use of fossil fuels. In order to reduce the amount of pollutants produced by fossil fuel, wet scrubber system is introduced in this experiment. Wet scrubber system is applied to a diesel engine (3,298 cc) and the amount of smoke is measured before and after the application in terms of aspect ratio, filling rate, and flow rate. The result showed a lot of smoke reduction when wet scrubber system was applied, and also the aspect ratios and water spray flow rate were the important factors to improve smoke reduction.