• 제목/요약/키워드: Smoke Simulation

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Visualization of Vortex Tube near Submerged Nozzle in Simulator of Solid Rocket Motor (고체로켓 모사장치 내삽노즐 주위의 와류튜브 가시화)

  • Kim, Dohun;Shin, Bongki;Son, Min;Koo, Jaye;Kang, Moonjung;Chang, Hongbeen
    • Journal of the Korean Society of Visualization
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    • v.11 no.2
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    • pp.34-40
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    • 2013
  • A flow visualization near submerged nozzle of solid rocket motor was conducted by experiments. A numerical simulation was also performed to reveal detailed phenomena. Radial cold flow simulating hot gas was introduced by a porous grain model which was manufactured by perforated steel plates. The grain model was mounted in high-pressure chamber which has quartz glass at the top of the grain model. From the high-speed images, a rotating vortex was observed and the two type of counter-rotating momentums were generated in numerical results. The rotating momentum was generated at the fin-slot grain because of unbalance between high-velocity flow from slots and low-velocity flow from fin-bases. As a result, roll torques can be produced by the rotating vortex tube.

A Numerical Study of Fire Development Characteristics on a Ro/Ro Ferry Vehicle Deck. (Ro/Ro 여객선 차량갑판의 화재 특성에 관한 수치 해석 연구)

  • Kim, Sung-Chan;Ryou, Hong-Sun
    • Journal of the Society of Naval Architects of Korea
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    • v.41 no.5
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    • pp.48-54
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    • 2004
  • The present study investigates the fire development characteristics on a Ro-Ro ferry vehicle using the modified FDS code considering droplet break-up. Numerical simulations are compared with model-scale tests for validation of field model. The predicted results such as smoke layer temperature and oxygen concentration are in good agreement with model-scale tests. Also, it is shown that water spray systems are very effective to control the fire development on a vehicle deck. These numerical simulations using a field model may be helpful in accomplishing the fire safety for marine vehicle.

A Development of Fire Training Simulator Based on Computational Fluid Dynamics Simulation (전산수치해석 기반 화재훈련 VR 시뮬레이터의 개발)

  • Cha, Moo-Hyun;Lee, Jai-Kyung;Park, Seong-Whan;Choi, Byung-Il
    • Korean Journal of Computational Design and Engineering
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    • v.14 no.4
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    • pp.271-280
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    • 2009
  • An experience based training system concerning various fire situations which may result many casualties has been required to make rapid decision and improve the responsiveness. Recently, the necessity of virtual reality (VR) based training system which can replace a dangerous full-scale fire training and be easily adopted to the training or evaluation process is increasing. This study constructed tile virtual environment according to pre-defined scenarios, utilized the FDS(Fire Dynamics Simulator), three dimensional computational fire analysis program, to derive numerically simulated data on the propagation of fire. Finally, by visualizing the realistic fire and smoke behavior through virtual reality technique and implementing real-time interaction, we developed a VR-based fire training simulator. Also, in order to ensure the sense for tile real of a virtual world and reaI-time performance at the same time, we proposed appropriate data processing and space search algorithms, demonstrate d the value of proposed method through experiments.

A Study on the Fire Safety Plan for Building Construction (건축물 건설공사 시 화재안전계획 수립에 관한 연구)

  • Jeong, Myeong-Jin;Lee, Myeong-Gu;Ham, Eun-Gu
    • Journal of the Korea Safety Management & Science
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    • v.14 no.4
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    • pp.31-37
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    • 2012
  • Recently buildings are constructed in larger and higher scales and becoming more complex. However from small to large scale buildings and on construction sites there still are fire safety accidents that occur continuously. Therefore to improve fire safety plan, examining the actual fire safety management and understanding fire risk analysis Using Fire Modeling through Computer Simulation. On this study, the permissible evacuation times were estimated for smoke fall, temperature, CO concentration, viability, etc. Fire safety management plans for fire safety were suggested.

Turbulence Generation and Advection in Smoke Using Stable Divergence-Constrained Moving Least Squares (안정적인 발산 제약 이동최소자승법을 이용한 연기의 난류 생성 및 이류)

  • Subin Lee;Jong-Hyun Kim
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2024.01a
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    • pp.407-410
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    • 2024
  • 본 논문에서는 Semi-Lagrangian 이류 과정에서 역추적(Backward tracing)한 위치의 주변 속도를 Divergence-constrained MLS(Moving least squares)를 이용하여 보간하고 그 결과를 이류된 속도 데이터의 외력으로 적용해 연기 시뮬레이션의 난류 표현을 개선할 수 있는 새로운 프레임워크를 제안한다. 일반적인 MLS는 고차보간법이기 때문에 시간에 따른 연속성 보장이 안 되기 때문에 그 결과가 노이즈한 형태로 나타난다. 본 논문에서는 연기의 원본 속도와 제안하는 기법을 통해 생성된 속도 간의 각도 변화를 통해 난류를 생성하며 이를 통해 안정적이고 연기의 밀도를 이류시킨다.

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Effect of Re-ventilated Fan Capacity on Road Tunnel Fire (제트팬 용량이 도로터널 화재에 미치는 영향)

  • Kim, Kang-Hee;Cho, Mok-Lyang;Kim, Tae-Kwon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.204-210
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    • 2019
  • In case of a fire inside a tunnel, unlike ordinary roads, it is very difficult for a driver to obtain visibility, and a large accident is highly likely to occur. In this study, the smoke behavior, visible distance, and CO concentration of a jet fan were analyzed using the NIST fire simulation (FDS). All analyses were set to HRRPUA (Heat Release Rate Per Area) 3.6MW/m and all the analysis times were set to 600s. In all analyses by CFD, the results were confirmed at y=30m and y=110m, and smoke behavior analysis, visible range analysis, and carbon monoxide concentration were confirmed according to the diameter and flow rate. As the size and flow rate of the jet fan increased, the visibility distance was high at y=30m, and the concentration of carbon monoxide was also confirmed to be 0 ppm. Therefore, proper setting of the jet fan diameter and flow rate will be an excellent solution for fires in tunnels, and taking refuge at upstream area of a re-ventilated fan can reduce the number of casualties.

Study on the Fire Risk Prediction Assessment due to Deterioration contact of combustible cables in Underground Common Utility Tunnels (지하공동구내 가연성케이블의 열화접촉으로 인한 화재위험성 예측평가)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.11 no.1
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    • pp.135-147
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    • 2015
  • Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.

A Study on Fire and Evacuation simulation analysis for use of Disaster Vulnerable Personal Evacuation Device (재난약자 대피 도움장치 활용을 위한 화재 피난 시뮬레이션 분석 연구)

  • Choi, Doo Chan;Hwang, Hyun Soo;Ko, Min Hyeok;Lee, Si Yu
    • Journal of the Society of Disaster Information
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    • v.16 no.4
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    • pp.824-831
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    • 2020
  • Purpose: In fire case, nursing hospitals are subject to considerable restrictions on evacuation due to the characteristics of occupants and vulnerable elements of buildings, it is important to make evacuation device for vulunerabale person, and need how to intend to increase the efficiency of evacuation by fire and evacuation simulation with helper Method: The smoke characteristics were analyzed by time through fire simulation, finally, the number of helpers according to the day and night was entered, and the evacuation completion time was compared and analyzed using the evacuation simulation. Result: It was found that the evacuation time was shortened by more than 20% when the evacuation assistance device was used for the vulnerable, and the evacuation time was delayed by almost 70% in case of a fire at night compared to the daytime. Conclusion: If the horizontal and vertical evacuation device are effectively utilized in actual fire situations, a strategy appropriate to the situation is deemed necessary. It is expected that evacuation efficiency will increase based on the use of horizontal evacuation evacuation device and vertical evacuation device by developing evacuation manuals

Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 (설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.7
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

Quadrangular Splatting based on SPH (SPH 기반의 사각 스플렛팅 가시화 기법)

  • Shin, Seung-Ho;Yoon, Jong-Chul;Lee, Jung;Kim, Chang-Hun
    • Journal of the Korea Computer Graphics Society
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    • v.14 no.4
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    • pp.27-33
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    • 2008
  • Physics-based graphic techniques are used when simulating and rendering natural phenomena such as smoke, water and flame with computational physics. We propose novel methods which render simulated particle data fast onto 3D using tetrahedron splat. We calculate the position and the normal vector of splat by SPH(smoothed particle hydrodynamics) method then we reconstruct splat into quadrangular pyramid to reduce seam. We implement this technique for SPH fluid simulation, and animate natural flow of water successfully.

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