• Title/Summary/Keyword: High pressurization

Search Result 102, Processing Time 0.023 seconds

The Influence on the Stack effect that Pressure differential system to smoke control in High-rise buildings (초고층 건축물에서 급기가압제연이 연돌효과에 미치는 영향)

  • Lim, Chae-Hyun;Park, Yong-Hwan
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.11a
    • /
    • pp.235-238
    • /
    • 2008
  • High-rise buildings with stack effect caused by the foreclosure, which significantly delayed the spread of a fire in effects of these stack effect driving force said. In this research on the stack effect of the lobby if the pressurization of the stairwell analysis of the pressure distribution of the CONTAMW. Overall, the pressurization of the lobby makes it stairwell amount of pressure(+) to the zone in pressure designed to prevent the spread of smoke control performance and found that, the way a normal state and sub-pressurization in the stairwell with stack effect of the turbulence Such as the formation of the upper flow, but, in the upper atmosphere with pressurization was formed by the underlying trend.

  • PDF

CAN-based Feedback Control System Applied to Korean high-speed Train Pressurization System considering Network Delay (지연시간이 고려된 CAN 기반 피드백 제어시스템의 한국형 고속전철 여압시스템 적용)

  • Kwak, Kwon-Chon;Kim, Hong-Ryeol;Kim, Joo-Min;Kim, Dae-Won
    • Proceedings of the KIEE Conference
    • /
    • 2002.07d
    • /
    • pp.2445-2447
    • /
    • 2002
  • In this paper, CAN-based feedback control system is proposed for the pressurization system of korean high-speed train. The control performance of the system is evaluated. According to the requirement of the pressurization system A process model considering network delay and an adaptive PID control method based on the process model are proposed here. And it is shown that the proposed adaptive PID control method considering the network delay has on adequate feature compared to some other existing methods consequently it can be considered to be applied the pressurization system of korean high-speed train.

  • PDF

A Study for Pressure Difference and Critical Velocity by Pressurization of Elevator Shaft at High Rise Apartment (고층 공동주택의 승강로가압을 이용한 차압 및 방연풍속에 관한 연구)

  • Park, Kyung-Hwan;Yoon, Myong-O
    • Fire Science and Engineering
    • /
    • v.25 no.4
    • /
    • pp.89-93
    • /
    • 2011
  • It is not recommended that elevator use for egress at (super) high rise buildings because elevator shaft main roles to spread of fire smoke. But in North America used to protect this area by elevator shaft pressurization. These tests are performed at high rise apartment to verify that elevator shaft pressurization can protect to spread of fire smoke or not. and verify to used for egress at fire. Pressurization at elevator shaft make pressure difference of 50 Pa all floor at 150 CMM because this method have low friction loss from air flow. Also when dwelling door and elevator door are opened that critical velocity is performed to protect of back-layering from fire room for escape routs by 180 CMM. Therefore through out these pressurization tests by elevator shaft are estimated to have less overpressure because supply air difference are low between to satisfy critical velocity at one door opened and maintain to pressure difference all doors closed. Finally we verified that disable or residual people can use elevator for egress at fire by elevator shaft pressurization.

Tasks for Development of Autogenous Pressurization System and Construction of Test Equipment (자가증기 가압시스템 개발과제 및 모사시험설비 구성)

  • Cheulwoong Kim;Jisung Yoo;Sangyeon Ji;Jae Sung Park
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.27 no.1
    • /
    • pp.49-57
    • /
    • 2023
  • The autogenous pressurization has been widely adopted for propulsion systems of next-generation reusable rockets due to its low cost and high reliability. The autogenous pressurization has a simple structure, but an understanding of the heat and mass transfer occurring inside the tank is essential. For this reason, a simulation test of the autogenous pressurization was conceived. The experiment equipment was constructed based on overseas pressurization test facilities cases and expert advice. Unlike the actual autogenous pressurization system, the propellant tank was insulated to exclude external influences. The pressurized gas supply line and the propellant pipe were separated. Using the manufactured autogenous pressure experiment equipment, it is possible to evaluate the condensation phenomenon of pressurants in cryogenic propellants, comparison of the efficiency of pressurization using helium and evaporated gas and the pressurization capacity according to the temperature of pressurant.

Elevator Pressurization in Tall Buildings

  • Klote, John H.
    • International Journal of High-Rise Buildings
    • /
    • v.2 no.4
    • /
    • pp.341-344
    • /
    • 2013
  • During a building fire, smoke can flow through elevator shafts threatening life on floors remote from the fire. Many buildings have pressurized elevators intended to prevent such smoke flow. The computer program, CONTAM, can be used to analyze the performance of pressurization smoke control systems. The design of pressurized elevators can be challenging for the following reasons: (1) often the building envelope is not capable of effectively handling the large airflow resulting from elevator pressurization, (2) open elevator doors on the ground floor tend to increase the flow from the elevator shaft at the ground floor, and (3) open exterior doors on the ground floor can cause excessive pressure differences across the elevator shaft at the ground floor. To meet these challenges, the following systems have been developed: (1) exterior vent (EV) system, (2) floor exhaust (FE) system, and ground floor lobby (GFL) system.

Effects of Non-meat Protein Binders and Acidification on the Efficiency of Cold-Set Pork Restructuring by High Pressure

  • Hong, Geun-Pyo;Chun, Ji-Yeon;Lee, Si-Kyung;Choi, Mi-Jung
    • Food Science of Animal Resources
    • /
    • v.32 no.3
    • /
    • pp.301-307
    • /
    • 2012
  • We investigated the effects of non-meat protein binders combined with glucono-${\delta}$-lactone (GdL) on the binding properties regarding restructured pork prepared by high-pressure treatment. Soy protein isolate (SPI), casein (CS), whey protein concentrate (WPC), and egg white (EW) were used as non-meat protein binders and compared with the control (no binder) and with the ${\kappa}$-carrageenan (KC) treatment. The compression and depression rates were 2.3 and 37 MPa/s, respectively, and pressurization was conducted at 200 MPa for 30 min at $4^{\circ}C$. After pressurization, the physical properties (pH, water-holding capacity, color, tensile strength, and microscopic structure) of the sample were evaluated. The combination of pressurization with acidification enabled cold-set meat binding, and the binding strength of restructured pork was enhanced by the addition of non-meat proteins. Among binders, SPI demonstrated the best efficiency in binding meat pieces. Therefore, the present study demonstrated that the combination of acidification and pressurization processes with the utilization of non-meat protein binders has a potential benefit in meat restructuring.

Rounded Entry Orifice Characteristics for Pressurization Control (가압제어용 둥근 유입형 오리피스 특성)

  • Chung, Yong-Gahp;Kwon, Oh-Sung;Jang, Je-Sung;Shin, Dong-Sung;Han, Sang-Yeop
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.401-404
    • /
    • 2008
  • Pressurization system in a liquid-propellant launcher supplies the controlled gas into the ullage volume of propellant tanks to feed propellants to combustion chamber by pressurizing propellants stored in propellant tanks. The ullage part of propellant tank should be constantly pressurized to supply the propellants stored in propellant tanks to turbo-pump or combustion chamber by pressurant pressurization system. Pressurant used to pressurize propellants is generally stored in a series of tanks at cryogenic temperature and high preassure inside an oxidizer tank. The reason is to store the quantity of pressurant as much as possible and to make pressurant tanks as small as (i.e. as light as) possible. However for test convenience pressurant tank is located at STP (standard temperature and pressure) environment in this study. Orifices are widely adapted to several pressurization systems in liquid rocket propulsion systems. Discharge coefficients of orifices are essentially needed for the optimized design of pressurization system in liquid rocket propulsion system. For this study gaseous nitrogen was served as pressurant and rounded entry orifices were employed. The forty-two (42) rounded entry orifices (the radii of curvatures are 0.5 and 1.0) have been tested experimentally in the supersonic flow region. The discharge coefficients of rounded entry orifices with inside diameters ranging from about 1.4 to 5.0mm was measured with 0.95 ${\sim}$ 0.99.

  • PDF

A Study on the Smoke Proof Measure of High Rise Buildings. (건축화재시 피난대책에 관한 연구 -고층건물의 제연을 중심으로-)

  • 이영재;이근영
    • Fire Science and Engineering
    • /
    • v.4 no.1
    • /
    • pp.3-12
    • /
    • 1990
  • This study is to Present the air Pressurization system of staircase as a way to decrease the injury of human life which is suffocated by smoke when the fire break out in building. 1) The best among an air pressurization system of stairshaft Is multiple air Injection system established to be situated an air injection point in each layer. 2) If the air pressurization system is also applied to the elevator accessory room to use commonly, it can prevent from the smoke spreading and pollution inside building caused by stack effect of elevator shaft. 3) For the reasonable and safe escape and air pressurization system must be carried out from the project of basic shape of building under the close cooperation with architect and fire protection expert.

  • PDF

Effects of Thermal Processing Combined with High Pressure on the Characteristics of Cooked Pork (초고압 열처리가 가열 돈육의 품질특성에 미치는 효과)

  • Hong, Geun-Pyo;Shim, Kook-Bo;Choi, Mi-Jung;Min, Sang-Gi
    • Food Science of Animal Resources
    • /
    • v.28 no.4
    • /
    • pp.415-421
    • /
    • 2008
  • This study evaluated the effects of thermal processing combined with high pressure on the properties of cooked pork. Pressurization followed by heating (PFH), heating followed by pressurization (HFP) and heating under pressurization (HUP) treatments were compared to a heated only control. Cooked meat without simultaneous pressurization showed little or no decrease in water binding properties relative to the control, regardless of the sequence of pressurization and heating. However, HUP treated pork had significantly higher water binding properties than the control (p<0.05). The pH values of all treatments were not significantly different with the exception of HUP at 300 MPa. The HUP treated pork showed the best tenderizing effects among all the treatments tested and the effect was more significant at increased pressure levels (p<0.05). In addition, increasing pressure levels significantly increased the L-values of pork (p<0.05). PFH and HFP treated pork had significantly lower a-values (p<0.05), while no significant differences were observed in HUP. HUP treated pork had the lowest b-values at 100 MPa. however, the differences were not significant at increasing pressure levels. These results indicate that heating under pressure is the best cooking condition for improving the quality characteristics of pork without adversely affecting its appearance.

A Study on Crack Propagation of Solid Propellant by Rapid Pressurization (고속가압에 의한 고체추진제의 균열진전평가에 관한 연구)

  • Ha, Jaeseok;Kim, Jaehoon;Yang, Hoyoung
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.16 no.6
    • /
    • pp.79-84
    • /
    • 2012
  • An experiment of rapid pressurization-induced crack propagation of solid propellant was conducted by using a windowed test chamber. A pre-cracked specimen of solid propellant is installed in the chamber, and highly compressed nitrogen gas in an accumulator pressurizes the chamber until the chamber pressure reaches set-up pressure to make the chamber depressurization. Pressure-time trace was obtained from the experimental result, and pressurization rate was defined from the trace. In this study, three pressurization rates (64.34, 73.86 and 85.44 MPa/s) are considered, and propagation lengths are measured. Also, a progression of the crack propagation recorded by a high-speed digital camera is presented.