• Title/Summary/Keyword: Smoke behavior

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Analysis of Smoke Behavior in Fire within Real-scale Theater Using FDS: Influences of Fire Curtain and Natural Smoke Vent Area (FDS를 이용한 실규모 공연장 무대 내 화재 시 연기 거동 분석: 방화막 및 자연배출구 면적의 영향)

  • Kim, Jae Han;Lee, Chi Young;Jeong, Lee Gyu;Kim, Duncan
    • Fire Science and Engineering
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    • v.32 no.6
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    • pp.7-14
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    • 2018
  • This study investigated numerically the influences of fire curtain and natural smoke vent area on smoke movement in the stage fire of a theater using FDS (Fire Dynamics Simulator). The dimension of the theater stage was 31 m in width, 34 m in depth, and 32 m in height. The area ratios between the natural smoke vent and stage were approximately 10%, 8%, 5%, and 1%. The gap distance between the fire curtain and proscenium wall was 0.5 m. The fire curtain and natural smoke vent area were observed to affect significantly the behavior of smoke movement to the auditorium and the mass flow rates of inflow and outflow through the natural smoke vent and proscenium opening. In addition, under the same natural smoke vent area, the pressure in the stage with a fire curtain was lower than that without a fire curtain.

A Study on Ventilation Effects on Smoke Behavior in Rescue Station for Tunnel Fires (철도터널 화재시 구난역 내의 연기거동에 미치는 배연효과에 관한 연구)

  • Jang, Won-Cheol;Kim, Dong-Woon;Lee, Seong-Hyuk;Ryou, Hong-Sun
    • Journal of the Korean Society for Railway
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    • v.11 no.3
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    • pp.294-299
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    • 2008
  • The present study investigates the ventilation effects on smoke spreading with the rescue stations. Experiments for tunnel fires were carried out for n-heptane pool em at different fire locations, and the heat release rates (HRR) were obtained by addition, using the commercial code (FLUENT), the present article presents numerical results for smoke behavior in railway tunnels with rescue station, and it uses the MVHS (Modified Volumetric Heat Source) model for estimation of combustion products resulting from the fire source determined from the HRR measurement. As a result, it is found that smoke propagation is prevented successfully by the fire doors located inside the cross-passages and especially, the smoke behavior in the accident tunnel can be controlled through the ventilation system because of substantial change in smoke flow direction in the cross-passages.

A Numerical Study on the Smoke Behavior by Solar Radiation through Ceiling Glass in Atrium Fires

  • Jeong, Jin-Yong
    • 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.

A study on related factors of parent's participation intention for early childhood secondhand smoke prevention (유아간접흡연 예방에 대한 부모의 참여의도 관련변인 연구)

  • Gwon, Gi-Nam;Min, Ha-Yeoung
    • Korean Journal of Human Ecology
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    • v.16 no.6
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    • pp.1097-1105
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    • 2007
  • This study aims to 1) examine the difference of parent's participation intention for early childhood secondhand smoke prevention depending on sex, education level, income level, and smoking or nonsmoking of parent, parent's knowledge and attitude of early childhood secondhand smoke 2) estimate the influence of independent factors on parent's participation intention for early childhood secondhand smoke prevention centering around factors stated previously, and 3) suggest effective strategies to ultimately encourage parent's behavior for early childhood secondhand smoke prevention. A total of 279 parents with four- and five-year-old day care children participated in this study. The following are the main results of this study. First, the higher the level of income parent had, the higher the level of participation intention for early childhood secondhand smoke prevention parent had. Second, nonsmoking parent exhibited higher level of participation intention than smoking parent. Finally, parent's knowledge and attitude of early childhood secondhand smoke had influence on parent's participation intention for early childhood secondhand smoke prevention, but parent's attitude had a high degree of influence on parent's participation intention.

Experimental and Numerical Studies on Heat/Smoke Behavior due to a Fire on Underground Subway Platform (II) - Numerical Approach - (지하철 역사 승강장 화재발생시 열/연기 거동 분석을 위한 실험 및 수치 연구(II) - 수치적 접근 -)

  • Chang, Hee-Chul;Kim, Tae-Kuk;Park, Won-Hee;Kim, Dong-Hyeon
    • Fire Science and Engineering
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    • v.20 no.3 s.63
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    • pp.15-20
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    • 2006
  • In this study the flow characteristics of smoke and heat on a bank type platform of the underground subway station are studied numerically by considering two different emergency operation modes. Effects of the natural flow through the tunnel and the stair ways are considered in the numerical simulations by using the measured velocities presented in Part I as the boundary condition. Distributions of heat, smoke, visible range and toxic gas on the platform are analysed for different smoke extraction flowrates corresponding to the two different emergency operation modes. The numerical results show that the extraction flowrate affects the smoke control performance significantly by improving the smoke removal performance as the extraction flowrate is increased.

Workplace Smoking Ban Policy and Smoking Behavior

  • Kim, Beom-Soo
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.5
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    • pp.293-297
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    • 2009
  • Objectives : To evaluate the impact of the workplace smoking ban in South Korea, where the male smoking rate is high (57%), on smoking behavior and secondhand smoke exposure. Methods : A workplace smoking ban legislation implemented in April 2003 requires offices, meeting rooms, and lobbies located in larger than 3,000 square meter buildings (or 2,000 square meter multipurpose buildings) should be smoke free. A representative cross-sectional survey, the third wave (2005) of health supplements in the National Health Nutrition Survey of South Korea, was used to measure the impact of the 2003 workplace smoking ban implementation on smoking behavior. It contained 3,122 observations of adults 20 to 65 years old (excluding selfemployed and non-working populations). A multivariate statistical model was used. The self-reported workplace smoking ban policy (full workplace ban, partial workplace ban, and no workplace ban) was used as the key measure. Results : A full workplace smoking ban reduced the current smoking rate by 6.4 percentage points among all workers and also decreased the average daily consumption among smokers by 3.7 cigarettes relative to no smoking ban. Secondhand smoke showed a dramatic decrease of 86 percent (= -1.74/2.03)from the sample mean for full workplace ban. However, public anti-smoking campaign did not show any significant impact on smoking behavior. Conclusions : The full workplace ban policy is effective in South Korea. Male group showed bigger impact of smoking ban policy than female group. The public antismoking campaign did not show any effectiveness.

The Analysis on the Effect of Supply Air Velocities by Location of Supply Air Damper on the Performance Efficiency of the Smoke Exhaust Systems (공기유입구 위치에 따른 유입공기의 풍속이 배연시스템 성능효율에 미치는 영향 연구)

  • Yeo, Yong-Ju;Lim, Chae-Hyun;Kim, Hak-Jung;Kim, Bum-Gyu;Park, Yong-Hwan
    • Fire Science and Engineering
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    • v.24 no.6
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    • pp.20-27
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    • 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.

A Study on the Smoke and Secondhand Smoke status, Knowledge about Smoking, Attitude for Smoking behavior and Smoking Cessation Intention of Seafarers (한국 해기사의 흡연 및 간접흡연 실태와 흡연에 대한 지식, 태도 및 금연의도)

  • Kim, Min-Kyeong;Kim, Jae-Hee
    • Journal of Digital Convergence
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    • v.18 no.9
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    • pp.413-421
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    • 2020
  • Because of space constraints of the ship, accessibility to supporting system for nonsmoking is poor in seafarers' group. This study was performed to find the smoking status, second-hand smoking status and factors related to smoking habit of Korean seafarers. So, we examined the rate of smoking and secondhand smoking, and knowledge about smoking, attitude for smoking behavior, smoking cessation intention and working environment related to smoking of 155 seafarers. Their smoking rate was 32.3% and secondhand smoke rate was very high by 86.5%. Their working place equipped a separate smoking room, but most of them had been smoked in where they were stayed. and we found the inadequate ventilation facility in 42.6%. Only 21.9% had a experience of education for smoking cessation. From the study Attitude for smoking behavior was negative and smoking knowledge was high. 90% of them tried to stop to smoke, but intention of smoking cessation was low. We need to motivate seafarers and increase their smoking cessation intention by regular education in available ways. From the study, we purpose that government will realign regulations related to ventilation facility and appointed smoking area on the board to prevent seondhand smoke, and the policy need to possess the regular survey of smoking status and customized smoking cessation education for seafarers.

Application of the ASE Model to the Assertive Behavior of Non-smoking College Students Under Secondhand Smoke Exposure (비흡연 대학생의 간접흡연 노출 시 주장행위 관련요인 - ASE 모델 적용을 중심으로 -)

  • Choo, Jin-A;Kim, Eun-Kyung
    • Research in Community and Public Health Nursing
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    • v.22 no.1
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    • pp.1-10
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    • 2011
  • Purpose:The present study was to apply the Attitudes-Social influence-Efficacy (ASE) model in order to identify factors associated with the assertive behavior of non-smoking college students when they are exposed to secondhand smokes in Korea. Methods: Data were collected from non-smoking college students (N=1,656, 76.6% female) at two universities in Seoul and Gyeonggi-do. The main outcome measure was the assertive behavior. ASE factors such as attitudes toward being assertive, social influences, and self-efficacy as well as socio-demographic, health-related, and smoking-related factors were self-administrated. Results: The mean of the assertive behavior (range 1~5 points) was 2.23;37.6% was not at all assertive, while 4.3% was always assertive. Higher assertiveness was significantly correlated with a higher level of positive attitude, social influence and self-efficacy (p<.05 for all). Stepwise multiple regression analyses showed that the social influence was the strongest factor associated with the assertive behavior (${\beta}=0.430$, p<.001, $R^2$=.246), followed by self-efficacy, motive to assertiveness, having any family member who had diseases, and male gender. These factors explained the assertive behavior by 39.7%. Conclusion: The ASE model may explain the assertive behavior of non-smoking college students under secondhand smoke exposure. Social influence and self-efficacy were significant factors associated with their assertive behavior.

Numerical study for smoke behavior in case of train fires in railway tunnel with axial fan vents (강제환기 통풍구가 설치된 철도터널 열차화재에서 연기거동에 관한 수치해석적 연구)

  • Kim, Dong-Hyeon;Shin, Min-Ho;Moon, Jung-Joo
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1998-2004
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    • 2003
  • Numerical study were performed to analyze for fire safety in railway tunnel with forced ventilation vents. For the condition of train fires with heat release rate of 30 MW, unsteady three dimensional analysis were carried out to investigate the effects of smoke movements, the heat transfer and $CO_2$ concentrations and in double track tunnel with two vents. Among three operation modes of forced ventilations at two vents, the exhaust-exhaust mode of the vent represents the best performance for the evacuation of passengers to avoid the fire.

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