• Title/Summary/Keyword: pressure housing

Search Result 274, Processing Time 0.026 seconds

An Experimental Study of Window Air Tightness according to Filling Piece Shapes (창호 풍지판 형상에 따른 기밀성의 실험적 연구)

  • Yun, Yura;Park, Jong-Jun;Kim, Young Il;Chung, Kwang-Seop
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.28 no.2
    • /
    • pp.63-68
    • /
    • 2016
  • To study the effect of installation and the shapes of filling pieces used for windows on the infiltration rate, infiltration tests were performed with two types of sliding windows and two shapes for the filling pieces. Infiltration occurred most at the top and bottom parts of the center location where two windows overlap, indicating the necessity of a filling piece to be installed at these locations. Infiltration velocity is proportional to the square root of the pressure difference, complying well with the theoretical correlation. Infiltration is reduced about 50% by the filling piece installation. This study shows that filling pieces are essential and their shapes play significant roles in reducing the infiltration of windows.

Housing Analysis for Ocean Radiation Detection (해양 방사선 탐지를 위한 하우징 분석)

  • Park, Gang-teak;Kim, Jong-Yeol;Jung, Hyun-kyu;Lee, Nam-ho;Hwang, Young-gwan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2017.10a
    • /
    • pp.714-715
    • /
    • 2017
  • Much of the interest in ocean radiation detection has been heightened as a lot of radioactivity has leaked to the ocean due to the accident at the Fukushima nuclear power plant in Japan. In the study, MCNP simulation for radiation detection in the ocean was performed. Unlike in the air, the marine environment must ensure the stability of the sensor from water depth, temperature, pressure, and salinity. In the marine environment, too much radiation is shielded. Therefore, it is an object to select a housing with a low radiation shielding ratio.

  • PDF

Dynamic PIV analysis of High-Speed Flow from Vent Holes of Fill-Hose in Curtain type Airbag (Dynamic PIV 기법을 이용한 커튼에어백 Vent Hole 고속유동 해석)

  • Jang, Young-Gil;Choi, Yong-Seok;Lee, Sang-Joon
    • 한국가시화정보학회:학술대회논문집
    • /
    • 2006.12a
    • /
    • pp.17-20
    • /
    • 2006
  • Passenger safety is fundamental factor in automobile. Among much equipment for passenger safety, the air bag system is the most fundamental and effective device. Beside of the front air bag system which installed on most of all automobiles, a curtain-type air bag is increasingly adapted in deluxe cars fur protecting passengers from the danger of side clash. Curtain type airbag system consists of inflator housing, fill hose, curtain airbag. Inflator housing is a main part of the curtain-type air bag system for supplying high-pressure gases to deploy the air bag-curtain. Fill hose is a passageway to carry the gases from inflator housing to each part of curtain airbag. Therefore, it is very important to design the vent holes of fill hose for good performance of airbag deployment. But, the flow information from vent holes of fill hose is very limited. In this study, we measured instantaneous velocity fields of a high-speed flow ejecting from the vent holes of fill hose using a dynamic PIV system. From the velocity Held data measured at a high frame-rate, we evaluated the variation of the mass flow rate with time. From the instantaneous velocity fields of flow ejecting from the vent holes in the initial stage, we can see a flow pattern of wavy motion and fluctuation. The flow ejecting from the vent holes was found to have very high velocity fluctuations and the maximum velocity was about 480m/s at 4-vent hole region. From the mass flow rate with time, the accumulated flow of 4-vent hole has occupied about 70% of total flow rate.

  • PDF

Simulated tropical cyclonic winds for low cycle fatigue loading of steel roofing

  • Henderson, David J.;Ginger, John D.;Morrison, Murray J.;Kopp, Gregory A.
    • Wind and Structures
    • /
    • v.12 no.4
    • /
    • pp.383-400
    • /
    • 2009
  • Low rise building roofs can be subjected to large fluctuating pressures during a tropical cyclone resulting in fatigue failure of cladding. Following the damage to housing in Tropical Cyclone Tracy in Darwin, Australia, the Darwin Area Building Manual (DABM) cyclic loading test criteria, that loaded the cladding for 10000 cycles oscillating from zero to a permissible stress design pressure, and the Experimental Building Station TR440 test of 10200 load cycles which increased in steps to the permissible stress design pressure, were developed for assessing building elements susceptible to low cycle fatigue failure. Recently the 'Low-High-Low' (L-H-L) cyclic test for metal roofing was introduced into the Building Code of Australia (2007). Following advances in wind tunnel data acquisition and full-scale wind loading simulators, this paper presents a comparison of wind-induced cladding damage, from a "design" cyclone proposed by Jancauskas, et al. (1994), with current test criteria developed by Mahendran (1995). Wind tunnel data were used to generate the external and net pressure time histories on the roof of a low-rise building during the passage of the "design" cyclone. The peak pressures generated at the windward roof corner for a tributary area representative of a cladding fastener are underestimated by the Australian/New Zealand Wind Actions Standard. The "design" cyclone, with increasing and decreasing wind speeds combined with changes in wind direction, generated increasing then decreasing pressures in a manner similar to that specified in the L-H-L test. However, the L-H-L test underestimated the magnitude and number of large load cycles, but overestimated the number of cycles in the mid ranges. Cladding elements subjected to the L-H-L test showed greater fatigue damage than when experiencing a five hour "design" cyclone containing higher peak pressures. It is evident that the increased fatigue damage was due to the L-H-L test having a large number of load cycles cycling from zero load (R=0) in contrast to that produced during the cyclone.

Development of Elastic Shaft Alignment Design Program (선체변형을 고려한 탄성 축계정렬 설계 프로그램 개발)

  • Choung Joon-Mo;Choe Ick-Heung
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.43 no.4 s.148
    • /
    • pp.512-520
    • /
    • 2006
  • The effects of flexibilities of supporting structures on shaft alignment are growing as ship sizes are Increasing mainly for container carrier and LNG carrier. But, most of classification societies not only do not suggest any quantitative guidelines about the flexibilities but also do not have shaft alignment design program considering the flexibility of supporting structures. A newly developed program, which is based on innovative shaft alignment technologies including nonlinear elastic multi-support bearing concept and hull deflection database approach, has S basic modules : 1)fully automated finite element generation module, 2) hull deflection database and it's mapping module on bearings, 3) squeezing and oil film pressure calculation module, 4) optimization module and 5) gap & sag calculation module. First module can generate finite element model including shafts, bearings, bearing seats, hull and engine housing without any misalignment of nodes. Hull deflection database module has built-in absolute deflection data for various ship types, sizes and loading conditions and imposes the transformed relative deflection data on shafting system. The squeezing of lining material and oil film pressures, which are relatively solved by Hertz contact theory and built-in hydrodynamic engine, can be calculated and visualized by pressure calculation module. One of the most representative capabilities is an optimization module based on both DOE and Hooke-Jeeves algorithm.

Seismic Performance Evaluation of Dam Structures and Penstock Considering Fluid-Structure Interaction (유체-구조물 상호작용을 고려한 댐 구조체와 수압철관의 내진성능평가)

  • Heo, So-Hyeon;Nam, Gwang-Sik;Jeong, Yeong-Seok;Kwon, Minho
    • Land and Housing Review
    • /
    • v.13 no.1
    • /
    • pp.141-150
    • /
    • 2022
  • Responding to the increasing demand for research on seismic resistance of structures triggered by a large-scale earthquake in Korea, the Ministry of the Interior and Safety revised the typical application of the existing seismic design standards with the national seismic performance target enhanced. Therefore, in this paper, the dam body of the aged Test-Bed and the penstock with fluid were modeled by the three-dimensional finite element method by introducing several variables. The current seismic design standard law confirmed the safety of the dam structure and penstock against seismic waves. As a result of the 3D finite element analysis, the stress change due to the water impact of the penstock was minimal, and it was confirmed that the effect of the hydraulic pressure was more significant than the water impact in the earthquake situation. When the hydrostatic pressure is in the form of SPH, it was analyzed that the motion of the fluid and the location of stress caused by the earthquake can be effectively represented, and it will be easier to analyze the weak part. As a result of the analysis, which considers penstock's corrosion, the degree of stress dispersion gets smaller because the penstock is embedded in the body. The stress result is minimal, less than 1% of the yield stress of the steel. In addition, although there is a possibility of micro-tensile cracks occurring in the inlet of the dam, it has not been shown to have a significant effect on the stress increa.

A Study on Economic Analysis and Performance Appraisal of Compact Type Variable Air Volume (컴팩트형 VAV 공조기의 성능평가와 경제성 분석에 관한 연구)

  • Kim, Dong-Cheol;Chung, Kwang-Seop;Kim, Young Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.27 no.1
    • /
    • pp.44-49
    • /
    • 2015
  • Ceiling cooling and heating system that consider load arrangement and space in the ceiling needs to be developed. Therefore, experimental and economic changes were done to verify the performance of compact type VAV. The test results were as follow. 1) Noise test result, measuring approximately 50.4 dB~56.6 dB (before ceiling in landfill), had a better ceiling deadline than the current measure, about a 10 dB noise reduction, so that the office baseline (40~50 dB) noise was judged to be less than test. 2) For the static pressure test result, taking out an outside hydrostatic 25 mmAq, 24.8 mmAq was measured, respectively, at the point. 3) For the life-cycle cost analysis result, the initial investment cost, maintenance replacement costs, and maintenance costs increased 0.2%, but the energy savings ratio was 19.5% while the whole life cycle savings of 40 years LCC was reduced 11.9%.

A Study on the Sound Insulation for Void-deck Slab Combined with Deck Plate and Polystyrene Void Foam (데크플레이트와 경량성형재가 결합된 슬래브의 차음성능에 대한 실물실험 평가)

  • Roh, Young-Sook;Yoon, Seong-Ho
    • Journal of the Korean Society of Safety
    • /
    • v.30 no.1
    • /
    • pp.60-65
    • /
    • 2015
  • This study is to explore floor impact sound and sound insulation of reinforced concrete structure with void-deck slab system which combines polystyrene void foam and T-shaped steel deck plate. A void-deck slab system can effectively reduce the amount of concrete used and hence the mass of a reinforced concrete slab. Also void slab system has dynamically favorable for bending. Three-bay 2-story building was constructed as a mock up test specimen using void-deck slab system and floor impact sound was measured to valuate sound insulation performance. Light weight floor impact and heavy weight floor impact were investigated. Light weight floor impact pressure levels were 32dB, 28dB, and 29db at representative locations which are $1^{st}$ level in the floor impact sound insulation performance grading system. The heavy-weight floor impact pressure levels were 44dB, 45dB, and 43dB at representative locations which are $2^{nd}$ level in the floor impact sound insulation performance grading system. Therefore void-deck slab system can be used in public housing apartment building in terms of not only effectively reduced construction materials but also floor impact sound insulation.

Application of Rock Splitter to Rock Excavation in an Open pit (노천현장 암 파쇄 굴착에 따른 할암공법의 적용성 고찰)

  • Won, Yeon-Ho;Kang, Choo-Won
    • Explosives and Blasting
    • /
    • v.28 no.1
    • /
    • pp.63-70
    • /
    • 2010
  • This study is investigated the extent of the noise and ground vibration in an adjacent zone of a cattle pen and an antiquated housing structures for judgement of the spot applicability on the extents of the noise and ground vibration of the rock-splitting method by an oil pressure. It is studied by measuring and analysing in an adjacent position the extents of the noise and ground vibration according to the work process of the rock-splitting method, such as drilling, rock-splitting, arranging rock, loading and by being compared with the permitted level on the noise and ground vibration fixed at the spot. To the results, it is identified that the influence to the noise has to be considered, even if the rock-splitting method is applied as an excavation method to lower a ground vibration by the classification on blasting method of the ministry of land, transport and marine affairs.

Analysis of Lubrication and Dynamic Characteristics of a Cylinder Block for Hydraulic Pump (유압펌프용 실린더 블록의 윤활 및 동특성 해석)

  • Ahn Sung-yong;Rhim Yoon-chul;Hong Yeh-sun
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
    • /
    • 2004.11a
    • /
    • pp.99-107
    • /
    • 2004
  • Lubrication characteristics between a cylinder block and a valve plate for high speed bent-axis type hydraulic pump play an important role in volumetric efficiency and durability of pump. In this paper, a finite element method is presented for the computation of the pressure distribution between a cylinder block and a valve plate for high speed bent-axis type hydraulic pump. Also, a Runge-Kutta method is applied to simulate the cylinder block dynamics of three-degrees of freedom motion. From the results of computation, we can draw two major conclusions. One is related to the fluid film characteristics between a cylinder block and a valve plate and the other is related to the average leakage that is determined by the pressure gradient and the clearance near the discharge port. The numerical results of cylinder block dynamics were compared with the experimental results using eddy-current type gap sensors those are fixed at a pump housing.

  • PDF