• Title/Summary/Keyword: wall height

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Thermal Effects in the Pool Fire of Fuels(I) (석유류 POOL FIRE에 있어서의 열적인 영향(I))

  • 정국삼;강민호;이덕영
    • Journal of the Korean Society of Safety
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    • v.11 no.1
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    • pp.75-83
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    • 1996
  • This paper was concerned with pool fire about many used kerosene and diesel oil. In order to know the thermal effects of kerosene and diesel oil, temperature change in the pool fire of these fuels were obtained as a variation of combustion time and the tank's height and diameter by using the data acquisition system, And fuel combustion velocity were derived as a function of the diameter and wall thickness of tanks and combustion time. As a result, when the tank's height was 15㎝, the greater diameter the higher temperature rising regardless of tank's wall thickness and fuels. But, when the tank's height is 30㎝, temperature rising was not higher than 15㎝. Also, temperature rising in the pool fire of kerosene much higher than diesel oil. Kerosene's combustion velocity was about two times faster than diesel oil. And, kerosene's combustion velocity was increased according to the increasing of tank's diameter and combustion time. But, diesel oil's combustion velocity was a little increased or not. Surrounding temperature change of tank with the pool fire was obtained temperature distribution of 0∼35℃ according to the change of tank's diameter and distance from the tank's wall.

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Internal Flow Characteristics of a Steelworks Sintering Cooler by the Duct Shape of Cooler Fan Outlet (제철소 소결냉각용 축류송풍기 출구 덕트 형상에 따른 내부유동특성)

  • Choi, Young-Do;Kim, Kyoung-Hoon
    • The KSFM Journal of Fluid Machinery
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    • v.17 no.5
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    • pp.72-77
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    • 2014
  • Because of overload working condition of sintering cooler, the cooler fan often suffers the break or damage of rotor blade and fixing shaft. Therefore, internal flow characteristics of a steelworks sintering cooler fan by the duct shape of the cooler fan outlet, such as duct outlet opening ratio, duct height and dividing wall shape on the duct outlet flow pattern are examined in detail. The results show that relatively short duct wall height and attachment of dividing wall shape improves flow patterns considerably.

Static Earth Pressure on Rigid Walls Backfilled by Cohesionless Soils (비점성토로 뒷채움한 강성옹벽에 작용하는 정적토압)

  • 정성교;백승훈
    • Geotechnical Engineering
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    • v.9 no.1
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    • pp.69-78
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    • 1993
  • The Coulomb and Rankine theories have been usually used for design of retaining walls, in which the earth pressures have been assumed as a triangular distribution For the rigid retaining w리1 with inclined bacuace and horizontal surface backfilled by cohesionless soils, the analytical method of earth pressure distribution has been newly suggested by using the concept of the flat arch. The active thrust obtained by this method agrees well with those by the existing theories, except the Rankine solution. The analyzed results show that the height to the center of pressure depends mainly on the inclination of the back wall and the wall friction, instead of 0.33H, where H is the wall height.

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A Study on the Behavior of Liquid Free Surface in a Shaking Vessel (진동교반조에서의 액자유표면의 거동에 관한 연구)

  • Lee, Young-Sei;Kim, Moon-Gab
    • Journal of the Korean Society of Industry Convergence
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    • v.3 no.3
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    • pp.209-217
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    • 2000
  • An attempt has been made to examine the highest liquid surface by means of measuring the movement of liquid free surface wave in the agitated vessel wall. Also, Relationship has been investigated between transition frequency, $N_z$ for behavior of liquid free surface and transition frequency for behavior of mass transfer coefficient in the agitated vessel wall. A surface wave is occured within agitated vessel, the highest height of wetted vessel wall, $h_w$ is coincided with the highest liquid surface, h. However the lowest height of wetted vessel, $h^*{_w}$ is not descended to lowest liquid free surface, $h^*$. The proposed model has been tested sucessfully for the behavior of liquid free surface.

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Analysis of Construction RCB Exterior Wall Formwork Placing High on Nuclear Power Plant (원자력 발전소 RCB 외벽 거푸집 1단 타설 높이별 시공성 분석)

  • Song, Hyo-Min;Shin, Yoon-Seok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.11a
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    • pp.205-206
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    • 2014
  • It is very important to reduce the construction duration of the Reactor Containment Building (RCB) when considering the more than 50 months on average from concrete placement to completion. The purpose of this study attempts to evaluate the single-stage workability of the system given a change in the height of the setting of RCB exterior wall formwork to be used in nuclear power plant construction. As a result of this study, it is possible height of 3.5m~4m uses formwork when analyzing the construction period and material costs an increase in formwork by concrete lateral pressure, to ensure the workability of the RCB exterior wall formwork. Through this study, I want to provide as basic data for the improvement of workability and RCB shortening the construction period.

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The Experimental Study on the Natural Ventilation Performance of Solar Chimney by the variation of Insulation Thickness and Height (단열재의 두께 및 연돌높이에 따른 태양열 굴뚝의 자연환기 성능에 관한 실험적 연구)

  • Cho, S.W.;Kim, D.W.;Im, Y.B.
    • Journal of the Korean Solar Energy Society
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    • v.22 no.3
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    • pp.39-46
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    • 2002
  • The results of experiment on the performance of natural ventilation by insulation thickness and height system of solar chimney are described. The 3-inside wall was made of concrete and 1-wall was made of glass. The two kinds of model experiment were performed. One was the varition of the 60cm, 90cm and 120cm of solar chimney, the other was the variation of the insulation thickness 10mm and 50mm and without insulation of outside wall of solar cimney. As the temperature difference between bottom and top expressed $1.7\sim2.9^{\circ}C$, air velocity measured $0.5\sim0.8m/s$ and ventilation rate was $194.4m^3/h$ in the case of the 120cm height of solar chimney, the respect of natural ventilation performance was superior to others cases in the first model experiment. Though the case of 120cm height of solar chimney was attached 50mm insulation the ventilation rate was not so much as the case of solar chimney was attached 10mm insulation. the temperature difference between bottom and top was the largest in the other cases. From this research, the natural ventilation performance of solar chimney was affected by not only height and insulation thickness of solar chimney but also wind velocity and directon.

Performance of cold-formed steel wall frames under compression

  • Pan, Chi-Ling;Peng, Jui-Lin
    • Steel and Composite Structures
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    • v.5 no.5
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    • pp.407-420
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    • 2005
  • This study presents the strength of braced and unbraced cold-formed steel wall frames consisting of several wall studs acting as columns, top and bottom tracks, and bracing members. The strength and the buckling mode of steel wall frames were found to be different due to the change of bracing type. In addition, the spacing of wall studs is a crucial factor to the strength of steel wall frames. The comparisons were made between the test results and the predictions computed based on AISI Code. The related specifications do not clearly provides the effective length factors for the member of cold-formed steel frame under compression. This paper proposes effective length factors for the steel wall frames based on the test results. A theoretical model is also derived to obtain the modulus of elastic support provided by the bracing at mid-height of steel wall frames in this research.

Numerical Analysis of Turbulent Heat Transfer on the Channel with Slat Type Blockage (障碍物 이 있는 平行平板사이 를 흐르는 亂流流動 의 熱傳達 解析)

  • 서광수;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.6 no.3
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    • pp.211-221
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    • 1982
  • Numerical analysis has been made on the heat transfer of two dimensional turbulent channel with a slat type blockage. Especially the effects of the height of slat and Reynolds number on the heat transfer characteristics of channel wall have been investigated. The methods of accelerating the convergence of the numerical solution of governing differential equation have been also examined. Line-by-line iterative method shows higher convergence rate than point-by-point iterative method for solution of both momentum equation and energy equation. The results show that the ratio of heat transfer coefficient of the wall near the blockage to that of the fully developed flow increase with increasing the ratio of blockage to channel height and decreasing the Reynolds number. These trends of variation of heat transfer coefficient with respect to the height of slat and Reynolds number agree with those of Sparrow's experiment on the pipe flow with slat type blockage.

A Study on the Variation of Collar Edge and Height according to the Angles of Collar Roll Line - Based on the Open Collar - (칼라 꺾임선(線) 눕힘각도(角度) 변화(變化)에 따른 외곽치수(外廓値數) 및 스탠드량 변화(變化)에 관(關)한 연구(硏究) - 오픈 칼라를 중심(中心)으로 -)

  • Lim, Ja-Young
    • Journal of Fashion Business
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    • v.9 no.2
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    • pp.143-159
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    • 2005
  • This study was done to provide basic data for clothing design and thus to contribute to the academic development at the clothing and textile area and collar roll line lay down angle variation at collar width on the open collar. The study was composed as tallows: 1. The variation at collar outer wall size increase collar roll line lay down angle size the more Increase. 2. The outer wall and stand height size increase aware at variation collar width at the more Increase. It is desirable that this study will be at help to enchancement of life style in garments and promotion of garments industury by developing the archetype basic collar pattern suitable to Korean women's garments.

Height-thickness ratio on axial behavior of composite wall with truss connector

  • Qin, Ying;Shu, Gan-Ping;Zhou, Xiong-Liang;Han, Jian-Hong;He, Yun-Fei
    • Steel and Composite Structures
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    • v.30 no.4
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    • pp.315-325
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    • 2019
  • Double skin composite walls offer structural and economic merits over conventional reinforced concrete counterparts in terms of higher capacity, greater stiffness, and better ductility. This paper investigated the axial behavior of double skin composite walls with steel truss connectors. Full-scaled tests were conducted on three specimens with different height-to-thickness ratios. Test results were evaluated in terms of failure mode, load-axial displacement response, buckling loading, axial stiffness, ductility, strength index, load-lateral deflection, and strain distribution. The test data were compared with AISC 360 and Eurocode 4 and it was found that both codes provided conservative predictions on the safe side.