• Title/Summary/Keyword: compartment

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A Study of Numerical Reproducibility for the Backdraft Phenomena in a Compartment using the FDS (FDS를 이용한 구획실 백드래프트 현상의 수치적 재현성에 관한 연구)

  • Park, Ji-Woong;Oh, Chang Bo;Choi, Byung Il;Han, Yong Shik
    • Journal of the Korean Society of Safety
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    • v.28 no.6
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    • pp.6-10
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    • 2013
  • A numerical reproducibility of the backdraft phenomena in a compartment was investigated. The prediction performance of two combustion models, the mixture fraction and finite chemistry models, were tested for the backdraft phenomena using the FDS code developed by the NIST. The mixture fraction model could not predict the flame propagation in a fuel-air mixture as well as the backdraft phenomena. However, the finite chemistry model predicted the flame propagation in the mixture inside a tube reasonably. In addition, the finite chemistry model predicted well the backdraft phenomena in a compartment qualitatively. The flame propagation inside the compartment, fuel and oxygen distribution and explosive fire ball behavior were well simulated with the finite chemistry model. It showed that the FDS adopted with the finite chemistry model can be an effective simulation tool for the investigation of backdraft in a compartment.

Numerical Study on the Validity of Scaling Law for Compartment Fires (구획 화재의 상사 법칙 유효성에 관한 수치해석 연구)

  • Ko, Gwon-Hyun
    • Fire Science and Engineering
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    • v.28 no.4
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    • pp.29-34
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    • 2014
  • In this study, to assess the validity of scaling law which was based on the ventilation factor and utilized in fields of compartment fires, numerical simulations were conducted on full- and 2/5 reduced-scale compartment fires using FDS and simulation results were compared with the previously published experimental data. The numerical modeling used in this study was verified by comparing the predicted temperature at several points of the upper layer with the experiment data. Temperature and concentration distribution inside of compartments and velocity profile at door of compartment are analyzed to assess the validity of scaling law. Comparison between the predicted results on the full- and reduced-scale compartments shows good agreements on the inner compartment flow patterns, outflowing flame patterns from the compartments, and vertical temperature distributions.

Surgery for a Case of Three-Compartment Trigeminal Schwannoma : Technical Aspects

  • Chung, Jong-Chul;Chung, Seung-Young;Kim, Seong-Min;Park, Moon-Sun
    • Journal of Korean Neurosurgical Society
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    • v.48 no.4
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    • pp.383-387
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    • 2010
  • Complete removal of three-compartment trigeminal schwannomas is a challenge to neurosurgeons. To expand exposure of each compartment, the combination and modification of skull base approaches are necessary. The 61-year-old woman was admitted with chronic headache. Preoperative magnetic resonance imaging showed $47{\times}50{\times}40\;mm$-sized tumor originating primarily in the middle cranial fossa extended to the posterior and the infratemporal fossa. We performed operation in five stage; 1. Zygomatic osteotomy, 2. Inferior temporal fossa plate removal and foramen ovale opening, 3. Cavernous sinus opening, 4. Tailored anterior petrosectomy, 5. Meckel's cave opening. Combination of skull base surgery should be concerned according to the patient. In this study, extradural basal extension with zygomatic osteotomy, interdural posterior extension with tailored anterior petrosectomy, and intracavemous exploration are reasonable options for remodeling three-compartment lesion into a single compartment. Tailoring of bone resection and exploring through natural pathway between meningeal layers accomplish single-stage operation for complete removal of tumors.

Experimental study on hydrogen behavior and possible risk with different injection conditions in local compartment

  • Liu, Hanchen;Tong, Lili;Cao, Xuewu
    • Nuclear Engineering and Technology
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    • v.52 no.8
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    • pp.1650-1660
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    • 2020
  • Comparing with the large containment, the gas can not flow freely within the local compartment due to the small volume of the compartment in case of serious accident, which affects the hydrogen flow distribution, and it will determines the location where high concentration occurs in compartment. In this paper, hydrogen distribution and possible hydrogen risk in the vessel under the different conditions are investigated. The results show that when the initial gas momentum is increased, the ability of gas enters into the upper region of the vessel will be strengthened, and the hydrogen volume fraction in the upper region of the vessel is higher. Comparing with horizontal source direction, when source direction is vertically towards upper space, hydrogen is more likely to accumulate in the upper region of the vessel. With the increasing of steam mass flow, the dilution effect of steam on the hydrogen volume fraction will be strengthened, while the pressure in the vessel is also increased. When steam flow is decreased, the hydrogen explosion risk is higher in the vessel. The experiment data can provide technical support for the validation of the CFD software and the mitigation of hydrogen risk in the containment compartment.

Study on Characteristics of Heat Release Rate in Compartment of Building for Scenario of Smoke Management (건축물 제배연시나리오 작성을 위한 구획실 발열특성 연구)

  • Kim, Jung-Yup;Shin, Hyun-Joon
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.398-403
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    • 2009
  • The theoretical bases on characteristics of heat release rate in compartment of building for scenario of smoke management are introduced and the numerical applications to simple compartment model are carried out. The growth stage which is important for smoke management design is modelled as t-squared fire curve including fire growth coefficient with related to growth rate. The conditions for the happening of flashover is presented such as $600^{\circ}C$ of temperature or $20kW/m^2$ of radiation heat flux. After the flashover happen, the fire in compartment changes to fully developed fire having the characteristics of ventilation-controlled fire. As the result of numerical analysis to simple compartment model, the time to reach 900K under ceiling for condition of medium growth is twice for condition of fast growth.

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Noise Estimation in a Passenger Compartment and Trunk Coupled System by Using the Vibro-Acoustic Reciprocity (진동-음향 상반성을 이용한 차실-트렁크 연성계의 소음평가)

  • Lee, Jin-Woo;Lee, Jang-Moo;Kim, Seock-Hyun;Park, Dong-Chul
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.618-622
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    • 2000
  • This paper describes the correlation between the interior noise and the trunk wall vibration. Using the vibro-acoustic reciprocity, effect of the trunk wall vibration on the compartment noise is investigated on a medium size car. In the low frequency range, vehicle interior noise is dominated by several acoustic modes of the passenger compartment and the vibration modes of the surrounding shell parts. Especially, vibration of the trunk wall radiates sound and it is transferred through holes on the package tray into the passenger compartment. This paper experimentally reveals that sound can be well produced at some particular vibration modes of the trunk lid and it strongly influences the compartment noise through package tray holes. Contributions of the trunk walls to the interior noise are estimated by measuring the acoustic-structural transfer function, based on the vibro-acoustical reciprocity theorem.

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Experimental Study on the Effect of a Metal Storage Cask and Openings on Flame Temperature in a Compartment Fire

  • Bang, Kyoung-Sik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.3
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    • pp.395-405
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    • 2020
  • Compartment fire tests were performed using kerosene and Jet A-1 as fire sources to evaluate the relationship between flame temperature and opening size. The tests were performed for a fire caused by the release of kerosene owing to vehicle impact, and for a fire caused by the release of Jet-A-1 owing to airplane collision. The compartment fire tests were performed using a 1/3-scale model of a metal storage cask when the flame temperature was deemed to be the highest. We found the combustion time of Jet-A-1 to be shorter than that of kerosene, and consequently, the flame temperature of Jet-A-1 was measured to be higher than that of kerosene. When the opening was installed on the compartment roof, even though the area of the opening was small, the ventilation factor was large, resulting in a high flame temperature and long combustion. Therefore, the position of the opening is a crucial factor that affects the flame temperature. When the metal storage cask was stored in the compartment, the flame temperature decreased proportionally with the energy that the metal storage cask received from the flame.

Treatments of the Compartment Syndrome of the Foot after the Calcaneal Fractures (종골 골절후 발생한 족부 구획 증후군의 치료)

  • Park, Yong-Wook;Chung, Yung-Khee;Yoo, Jung-Han;Jun, Deuk-Soo;Hwang, Pil-Sung
    • Journal of Korean Foot and Ankle Society
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    • v.4 no.2
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    • pp.93-99
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    • 2000
  • Eleven patients with calcaneal fracture had 2 acute compartment syndrome of the feet and 9 late complication of the compartment syndrome of the feet. An interstitial pressure of more than 30 mmHg in either the central or interosseous compartment was considered pathologic and was treated by fasciotomy performed medially. Rigid claw toe deformity was treated by excision of the head and neck of the proximal phalanx, dorsal capsular release of the metatarsophalangeal joint, and lengthening of the extensor tendon. Patients were evaluated at a mean of 35 months(range, 21 - 44 months) after operation, and the examination was directed specifically toward symptoms and signs of myoneural ischemia, and walking pain. At follow-up, 2 patients with acute compartment syndrome of the foot had no evidence of myoneural ischemia, 9 patients with claw toe deformity had no pain with walking. Based on our clinical observations, we concluded that compartment syndrome of the foot may occur after the calcaneal fracture and fasciotomy is effective treatment for the prevention of the long term sequelae of this debilitating condition.

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Case of Abdominal Compartment Syndrome Treated by using a Bedside Open Linea Alba Fasciotomy (외상에 의한 후복막 출혈환자에서 발생한 복부구획증후군을 침상 옆 백선 근막 절개술로 치료한 증례)

  • Kim, Ji-Hoon T.;Han, Myung-Sik;Choi, Gun-Moo;Jang, Hyuck-Jae;Kwak, Jin-Ho;Kim, Ji-Hoon S.
    • Journal of Trauma and Injury
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    • v.24 no.1
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    • pp.56-59
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    • 2011
  • Abdominal compartment syndrome (ACS) is a life-threatening disorder caused by rapidly increasing intra-abdominal pressure. ACS can result in multiorgan failure and carries a mortality of 60~70%. The treatment of choice in ACS is surgical decompression. There are very few reports of ACS and experience in Korea. We report 12-year-old male patient who developed an abdominal compartment syndrome due to traffic-accident-induced retroperitoneal hematomas, Which was successfully treated by performing a bedside emergency surgical decompression with open linea alba fasciotomy with intact peritoneum. When patients do not respond to medical therapy, a decompressive laparotomy is the last surgical resort. In patients with severe abdominal compartment syndrome, the use of a linea alba fasciotomy is an effective intervention to lower intra-abdominal hypertension (IAH) without the morbidity of a laparotomy. Use of a linea alba fasciotomy as a first-line intervention before committing to full abdominal decompression in patients with abdominal compartment syndrome improves physiological variables without mortality. Consideration for a linea alba fasciotomy as a bridge before full abdominal decompression needs further evaluation in patients with polytrauma abdominal compartment syndrome.

Treatments of the Compartment Syndrome of the Foot after the Calcaneal Fractures (종골 골절후 발생한 족부 구획 증후군의 치료)

  • Park, Yong-Wook;Chung, Yung-Khee;Yoo, Jung-Han;Jun, Deuk-Soo;Whang, Pil-Sung
    • Journal of Korean Foot and Ankle Society
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    • v.3 no.1
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    • pp.12-18
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    • 1999
  • Eleven patients with calcaneal fracture had 2 acute compartment syndrome of the feet and 9 late complication of the compartment syndrome of the feet. An interstitial pressure of more than 30 mmHg in either the central or interosseous compartment was considered pathologic and was treated by fasciotomy performed medially. Rigid claw toe deformity was treated by excision of the head and neck of the proximal phalanx, dorsal capsular release of the metatarsophalangeal joint, and lengthening of the extensor tendon. Patients were evaluated at a mean of 35 months(range, 21 - 44 months) after operation, and the examination was directed specifically toward symptoms and signs of myoneural ischemia, and walking pain. At follow -up, 2 patients with acute compartment syndrome of the foot had no evidence of myoneural ischemla, 9 patients with claw toe deformity had no pain with walking. Based on our clinical observations, we concluded that compartment syndrome of the foot may occur after the calcaneal fracture and fasciotomy is effective treatment for the prevention of the long term sequelae of this debilitating condition.

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