• Title/Summary/Keyword: Sprinkler systems

Search Result 61, Processing Time 0.031 seconds

Distribution Characteristics of a Mini -Sprinkler without a Bridge (Non-bridge 형 미니스프링쿨러의 살수 특성)

  • 이남호
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.42 no.1
    • /
    • pp.66-72
    • /
    • 2000
  • A study was conducted to find distribution patterns of minisprinkler without a bridge for the desing of microirrigation systems. The experiments were executed in a plastic house to minimize the effect of the wind. Data were collected at four different operation pressures and at 3 different riser heights. Sprayed water were collected by aluminium cans with 65mm diameter and 100mm height placed at 0.3m grid spacing . A schematic distribution pattern with distance from a minisprinkler was suggested for the layout design of the minisprinkler. Distribution pattern of the minisprinkler was found irregular in space. Distributin performance characteristics of the minisprinkler such as effective radius. , effective area, mean application depth, absolute maximum application depth, effective maximum application depth and coefficient of variation were determined. It was indicated that there is a trend of decrease in variation coefficient adn better water distribution by the increase in operation pressures and riser heights.

  • PDF

Extinguishing Characteristics of Cooking Oil Fire by Water Mist added with AFFF Agent (수성막포 약제를 첨가한 미분무수의 식용유 화재 소화특성)

  • Shin, Chang-Sub;Kim, Seong-Yong
    • Journal of the Korean Society of Safety
    • /
    • v.24 no.5
    • /
    • pp.21-27
    • /
    • 2009
  • Effective way of cooking oil fire extinguishment is using water mist system which has cooling and smothering effects. Low pressure water mist system has advantage because it is compatible with existing sprinkler systems. To increase the effectiveness of low pressure water mist system, additives can be used which increase the momentum of water particle and the chemical effect. In this experiment, aqueous film forming form(AFFF) agent is used as additive and the effect of additive concentration and water pressure are experimented. For the extinguishment of cooking oil fire such as soybean and olive oils, AFFF agent is effective and can decrease the fire extinguishing time and water consumption.

A Study on Assessment of Fire and Evacuation Safety in Environmental Energy Facilities (환경에너지시설의 화재 및 피난 안전성 평가에 관한 연구)

  • Jeon, Yong-Han;Han, Sang-Pil
    • Journal of the Korea Safety Management & Science
    • /
    • v.21 no.4
    • /
    • pp.39-44
    • /
    • 2019
  • In this study, fire and evacuation safety of environmental energy facilities using fire and evacuation simulation was examined as part of performance-oriented design. The worst-case fire scenarios in which fire-fighting facilities such as sprinkler fire extinguishing and smoke control systems are not working, and the FDS analyzes the visibility, temperature distribution, and carbon monoxide concentration distribution through FDS. The safety was examined. As a result, it was proved that evacuation could limit the visibility, temperature, and carbon monoxide concentration in a smooth range, based on the safety standards set by relevant laws. In other words, it was possible to verify the safety of fire and evacuation for environmental energy facilities where a large amount of combustibles and fires coexist.

Control of RC-Helicopter by Using Fuzzy Sliding Mode Controller

  • Hiramatsu, Tomoyasu;Miyazaki, Michio
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1998.10a
    • /
    • pp.210-214
    • /
    • 1998
  • Radio-Controlled helicopter has superior movement abilities like as hovering or backward move. So it has been used as a sprinkler of agricultural medicines or an observer of dangerous area such as a volcano, etc. But its operation is not simple because it has many control factors and they interfere with each other. Therefore the helicopter is not controlled by simple theory in the case of automatic operation. Then fuzzy sliding mode control, which has fastness, fineness and robustness, is thought to be suitable to satisfy various requirements of the helicopter operation. In this work, the fuzzy sliding mode control was applied to the flying of RC helicopter, As tile result, it was controlled with good performance.

  • PDF

A Study of Computational Fluid Dynamics Analysis for the Water Spray Distance of Long Jet Monitor (Long Jet Monitor의 소화수 분사 거리에 대한 유동 해석적 연구)

  • Jae-Sang Jo
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.26 no.5
    • /
    • pp.907-913
    • /
    • 2023
  • Currently, the sprinkler method is widely used as an initial suppression method in existing firefighting systems. However, this method can cause significant damage to both equipment and facilities in the hydration area. To minimize this damage, fire extinguishing monitors are being developed that can spray fire extinguishing water directly at the point of fire. These monitors are installed on the top floor of the ship, such as the Living Quarter and Ventilation System. While conventional fire extinguishing monitors focus on lightweight research with a short spray port and require a spray distance of about 40 to 45m, recent developments necessitate a longer spray port, similar to a water cannon, requiring a spray distance of about 70 to 75m. This study aims to predict the injection distance of both the existing ship-installed fire extinguisher and the long spray port fire extinguisher through hydrodynamic computer analysis, and to determine whether the injection distance has increased.

A Study on Measures to Improve Smoke Control Performance in Case of Fire in a Clean room as an LCD Manufacturing Process (LCD 제조공정 클린룸의 화재시 CFD를 이용한 제연성능 개선대책에 관한 연구)

  • Son, Bong-Sei;Jang, Chan-Hee
    • Fire Science and Engineering
    • /
    • v.26 no.5
    • /
    • pp.41-47
    • /
    • 2012
  • As a core process in the manufacture of state-of-the-art industrial technologies such as semiconductor and LCD, a clean room is the most important process which can affect the performance and quality of products drastically. Nevertheless, scientific research on comprehensive safety measures from a fire protection standpoint is not being carried out in Korea. This study aims to derive measures to improve smoke control systems by identifying performance and problems of smoke systems installed in clean rooms as an LCD manufacturing process and analyzing fire and evacuation simulations considering several scenarios. As a result of analysis of fires and smoke in a clean roomas an LCD manufacturing process, it is found to be necessary to stop air handling units through interlocking in case of a fire and exhaust smoke out of the room through the top of FAB in consideration of buoyancy of smoke. It is also found to be necessary to install quick response sprinkler heads and accessories to accelerate the response time, because the heat-accumulating performance of sprinkler heads decreases in this application. Despite its low density of dwelling due to the automation process, clean room is characterized by an array of complex production equipment and working environment requiring dustproof clothes, which makes it difficult to acquire evacuation safety performance. Thus, thorough control of danger factors in processes and periodic education and training are required. It is also necessary to establish a level of domestic technologies equivalent to the level of standards of advanced countries in fire protection.

Water Balance-based Farmland Suitability for Southern-type Garlic Cultivation (난지형 마늘의 농업수리학적 재배적지 분류)

  • Kim, Yong Wan;Hong, Suk Young;Kim, Yi Hyun;Jang, Min Won
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.54 no.6
    • /
    • pp.19-28
    • /
    • 2012
  • This study carried out farmland suitability analysis for southern-type garlic cultivation considering soil and temperature as well as water deficit conditions. The spatial extent was limited within the area derived by Kim et al. (2012) using just soil and temperature constraints. Daily soil moisture was simulated using a one-layer soil water balance model at a $100{\times}100m$ grid unit, and then annual water deficit was calculated from 2000 to 2010. The farmland suitability was classified as four steps: best suitable, suitable, possible, and low productive. As a result, total area of best suitable or suitable farmland was about 375,900 ha, and Gimje-si and Haenam-gun were appeared as the largest favorable area for southern-type garlic cultivation. The best suitable or suitable area at Haenam-gun, Goheung-gun, Shinan-gun, Namhae-gun, and Muan-gun, major production regions of southern-type garlic, were extracted as 20,187 ha, 13,018 ha, 4,715 ha, 1,319 ha, and 349 ha, respectively. On the other hand, the result showed that the adoption of sprinkler irrigation systems might be critical in cultivating the southern-type garlic at some regions having poor water balance.

A Study on the Seismic Design for Water Exthinguishing Piping Systems (수계 파이프 시스템의 내진설계에 관한 연구)

  • Lee, Dong-Myung
    • Fire Science and Engineering
    • /
    • v.22 no.1
    • /
    • pp.10-15
    • /
    • 2008
  • In this study, seismic design in sprinkler head pipeline of water extinguishing system has been carried out. This study describes a generation of artificial earthquake wave compatible with seismic design spectrum, and also analyzed the dynamic response spectra by the simulated earthquake motion. This study constructed powerful engineering base for seismic design, and presented seismic design techniques of water and gas extinguishing piping system. Also, this study readied basis that can apply seismic design and performance estimation of fire fighting system and performance rating as well as pipeline of water extinguishing system from result of this research. Hereafter, if additional research by earthquake magnitude and ground kind is approached, reliance elevation, safety raising and performance based design of fire fighting system see to achieve.

A Numerical Analysis Study on the Influence of the Fire Protection System on Evacuation Safety in Apartment Houses (공동주택 건축물 내 화재방호시스템이 피난안전성에 미치는 영향에 대한 수치해석적 연구)

  • Kim, Hak Kyung;Choi, Doo Chan;Lee, Doo Hee;Hwang, Hyun Soo;Kim, Hee Moon
    • Journal of the Society of Disaster Information
    • /
    • v.18 no.1
    • /
    • pp.38-50
    • /
    • 2022
  • Purpose: The goal of this research is to create a numerical analytic database that may assist fire prevention managers and building officials in prioritizing items that need to be addressed in order to improve evacuation safety performance while working within a constrained budget and time frame. Method: It was carried out utilizing the CFD Tool, a quantitative evaluation approach, to assess evacuation safety. One direct staircase-type apartment houses and one corridor-type apartment were chosen to make it. Result: In the fire compartment category, Apartment A's evacuation time was around 130 percent longer than that of sprinkler facilities. Conclusion: Fire prevention managers and building officials feel that starting with a single level and implementing "dwelling unit separations" will increase evacuation safety, and that maintaining fire compartments and sprinkler systems at all times will be effective. Because of the limited characteristics of smoke propagation in corridor-type apartments compared to direct staircase-type flats, it is thought that fire extinguishing equipment should be addressed.

Development of Bottom Irrigation System and Management Method for Cultivation of Bonsai (분재(盆栽)의 대량재배(大量栽培)를 위한 관수(灌水)시스템과 관리방법(管理方法)의 개발(開發))

  • Lee, Ki-Eui;Jeong, Jin-Hyung
    • Journal of Forest and Environmental Science
    • /
    • v.19 no.1
    • /
    • pp.48-68
    • /
    • 2003
  • There have been some problems of high labor. low productivity in the existing systems of bonsai cultivation. This study was conducted to cultivate a large quantity of hig-quality bonsai through the development of bottom irrigation system and management method. Bonsai placed on the FRP bed were grown very well by bottom irrigation system compared with direct watering and sprinkler system. It was concluded that bottom irrigation system was possible to reduce considerable manual labor and produce mass production of high-quality bonsai within shorter periods. This research was finally found that the growth was significantly better and earlier production was certain in the vinyl house, had another advantage which could cultivate less cold-resistant species and therefore broadened a range of species selection for market supply. Cultivation techniques by the use of vinyl house and bottom irrigation system developed was quite effective for early production of bonsai as well as for high productive and value added. This project developed a new practical techniques and systems which can make mass and early production of bonsai with high quality through input of less labor. Interest in bonsai is now expanding in landscape horticulture and other fields concerned, and bonsai export of our country is also increasing. Results from this research will make a great contribution to enhancing of bonsai cultivator's competitive position in world markets and to improving of their annual income.

  • PDF