• Title/Summary/Keyword: Fire suppression

Search Result 337, Processing Time 0.022 seconds

Evaporation Cooling Phenomena of Droplets Containing Fire Suppression Agents (화제 억제제가 첨가된 수용액 액적의 증발냉각 현상)

  • 유갑종;방창훈;김현우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.9
    • /
    • pp.895-903
    • /
    • 2001
  • Evaporation cooling phenomena of droplets containing fire suppression agents on a hot metal surface were experimentally investigated. Solution of water containing potassium acetate (30-50% by weight) and sodium bromide (10-30% by weight) were used in the experiments, and surface temperatures were ranged from 70-116$^{\circ}C$. The evaporation time of the droplet on the heated surface was determined by using frame-by-frame analysis of the video records. It is found that the apparent evaporation time is shorter in turns of pure water, sodium bromide solution and potassium acetate solution. However, the time averaged heat flux is higher in turns of pure water, sodium bromide solution and potassium acetate solution. In-depth temperature variation of the hot metal does not occur significantly by the kinds of additive.

  • PDF

Implementation of Automatic Extinguishing System for fire suppression of vehicle (차량 화재 진압을 위한 자동 소화 시스템 구현)

  • Ryu, Hye-Yeon;Kim, Man-Ho
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.22 no.2
    • /
    • pp.227-233
    • /
    • 2019
  • In recent years, vehicle fires account for the second highest rate after residential fires. It accounts for more than 10.7% of the total fire occurrence rate. Vehicle fires are very difficult to evolve at an early stage. Most of the vehicles are burned down in the event of a fire, resulting in a lot of physical and personal damage. In the EU and other countries, efforts are being made to install automatic fire extinguishing systems in preparation for vehicle fires. In addition, since the automatic fire extinguishing system applied to a vehicle must operate in a moving state of a car, a method for detecting a fire is needed. Therefore, this paper proposes a structure of an automatic fire extinguishing system that can evolve a fire when a fire occurs in a commercial vehicle among various vehicles. Especially, it confirms the feasibility of the automatic fire extinguishing system simulated in the laboratory environment and confirms its applicability.

Effects of Spray Characteristics of Water Mist on The Extinction of a Liquid Pool Fire (분무수 분무특성이 액체연료 Pool 화염의 소화에 미치는 영향)

  • Kim, Ho-Young;Oh, Sang-Youp;Chung, Jin-Taek
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.28 no.12
    • /
    • pp.1591-1599
    • /
    • 2004
  • A series of experiments were conducted to study the effectiveness of the extinction of a liquid pool fire with two different water atomizing nozzles. Fire source is a small-scale circular stainless steel pan of 120mm in diameter with the fuels of hexane and ethanol. K-type thermocouples were used to measure the flame and fuel temperature along the pool centerline and under fuel surface. A digital camera was used to visualize the process of the fire suppression. The experimental results show that water mist droplet size is l15∼180${\mu}{\textrm}{m}$ with nozzle A and 130∼190${\mu}{\textrm}{m}$ with nozzle B. The extinguishing time of pool fire was reduced with the increase of pressure. When water droplets are small, they do not reach the flame base since they may be deflected or evaporated by the fire plume. However, influence of flow rate is more important than droplet size on fire extinction. Among the fire extinction mechanisms, drop of flame temperature is superior to suffocation of $O_2$ concentration.

THE DEVELOPMENT OF A UV FLAME DETECTOR FOR THE AUTOMATIC FIRE SUPPRESSION SYSTEM FOR ENGINE COMPARTMENT FIRES

  • Lim, Sung-Mook;Jung, Ki-Chang;Kim, Eung-Sik;Kim, Hong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 1997.11a
    • /
    • pp.590-597
    • /
    • 1997
  • In this work, a new type of UV flame detection system was developed. In order to measure the performance of UV flame detector, various kinds of experiments was performed. The results show that the maximum response time of the UV flame detector is 0.2 seconds when the detection distance is one meter The advantages of this system include wide area, high speed response and high sensitivity. After testing the W flame detector in engine compartment it detected fire within 0.09 seconds and extinguished within 5 seconds. Hence, the UV flame detector can be applied in automatic fire suppression system for automobiles.

  • PDF

Survey on a Research for Fire Safety in Space with the Understanding of Combustion Characteristics in Microgravity based on NASA's Space Research Program (NASA의 우주 연구 프로그램에 따른 미소 중력하에서의 연소 특성 및 화재 안전 연구 개괄)

  • Sohn, Chae-Hoon;Son, Young-Jin
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.11 no.3
    • /
    • pp.65-72
    • /
    • 2007
  • Fire is one of important checkpoints in crewed exploration systems, where men inhabit in space. In space, astronaut can't escape from fire out of a spacecraft and not expect any help of fire fighters, either. Accordingly, the best way to stand against fire is to prevent it. But, when fire occurs in space, flame behaviors are quite different from those observed on earth because of micro- or zero-gravity in space. The present paper introduces major research results on flame behaviors under microgravity and fire prevention, detection, and suppression in crewed exploration spacecrafts and international space station based on NASA's FPDS research program.

Evaluation of the Closed-type Sprinkler Head Activation Time (밀폐형 스프링클러 헤드의 동작시간 평가)

  • Moon-Hak, Jee;Sung-Yull, Hong
    • Fire Science and Engineering
    • /
    • v.18 no.3
    • /
    • pp.1-8
    • /
    • 2004
  • As a predominant active fire suppression method, closed-type sprinkler systems are used for the purpose of fire control and suppression at the nuclear power plants as well as the industrial facilities. It goes without saying that the proper selection of the system guarantees the adequate actuation of the thermal device. Consequently, the appropriate evaluation should be executed for the thermal behavior with the theoretical and empirical approach. For this purpose, the comparison of activation time for the fusible-link type sprinkler head with the simplified fire case and t-square fire growth case was evaluated. At this paper, the comparison output was presented with the tendency of thermal behavior. In addition, we issued some technical comments for the most appropriate equation in case of the estimation of the sprinkler head activation time. We also raised some idea that should be incorporated for the usage of the t-square equation for the realistic application in the field of the performance-base fire protection approach.