• Title/Summary/Keyword: inner temperature

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A Study on the Flame Temperature and KL Value in Inner and Outer Cavity in a D.1. Diesel Engine (디젤엔진에서 Cavity 내 .외측의 화염온도와 KL치에 관한 연구)

  • 이태원;윤수한;정성식;하종률
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.3
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    • pp.18-27
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    • 2002
  • Flame behavior in inner and outer the cavity and flame temperature have an important influence on the formation and oxidation of NOx and soot. Therefore, in this study, the combustion chamber of toroidal and reentrant that have different flow characteristics of inside and outside the cavity and load, and so forth are determined as parameters of experimental conditions. An attempt has been made to obtain the effect of flame temperature and KL value in idler and outer cavity on the formation and oxidation of soot using the two-color method.

The Effect on Cabinet Deformation by Bead of Inner Case (가정용 냉장고의 냉동실 내벽의 비드가 케비넷 변형에 미치는 영향)

  • Cho, J.R.;Zhai, J.G.;Shin, M.G.;Kim, J.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2009.10a
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    • pp.427-428
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    • 2009
  • In the manufacture process of refrigerator cabinet, polyurethane(PU) liquid firstly is injected between outer plate and inner case in high temperature about $40^{\circ}C$, and PU foam is generated and solidified to the room temperature. There will be great residual stress in the PU foam, especially at the corners after the whole refrigerator is completely assembled. The stress condition will become more complicated under operating condition because of the large temperature difference between the freezing room and outer plate. And also, there are great differences of properties for plastic and steel which would cause different deformation under temperature gradient. The steel outer plate would expand compared to the PU foam or ABS material under operation condition, which induces a thermally bowing deformation in the refrigerator cabinet. The objective of this paper is to design an optimum bead structure or to use reinforcement in the refrigerator except for improving material properties in order to decrease the deformation.

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A Numerical Study of Natural Convection in a Square Enclosure with a Circular Cylinder at Different Vertical Locations (원형 실린더가 존재하는 사각형 실린더 내부의 자연대류에 관한 수치적 연구)

  • Kim, Byeong-Su;Lee, Dae-Sung;Yoon, Hyun-Sik;Lee, Hyun-Goo;Ha, Man-Yeong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.3 s.258
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    • pp.273-282
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    • 2007
  • Numerical calculations are carried out for the natural convection induced by temperature difference between a cold outer square cylinder and a hot inner circular cylinder. A two-dimensional solution for unsteady natural convection is obtained, using the immersed boundary method (IBM) to model an inner circular cylinder based on finite volume method, for different Rayleigh numbers varying over the range of $10^4\;to\;10^6$. The study goes further to investigate the effect of an inner cylinder location on the heat transfer and fluid flow. The location of inner circular cylinder is changed vertically along the center-line of square enclosure. The number, size and formation of cell strongly depend on Rayleigh number and the position of inner circular cylinder. The changes in heat transfer quantities have been presented.

Study on Process Conditions for Automatic Debarking and Xylem Separator for Paper Mulberry (닥나무 자동 흑피 및 목질부 제거 장치의 공정 조건 연구)

  • Choi, Si-Hyuk;Kwon, Oh-Hun;Kim, Hyun-Chel
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.3
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    • pp.36-44
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    • 2013
  • This study is focused on the debarking and xylem separation yield of Paper Mulberry. We investigated the most efficient manual on the automatic debarking and xylem separator machine. The bast tissues of Paper Mulberry were separated in three layers including black outer layer, green inner layer, and white inner layer. A target is to save the white inner layer of these three layers as much as possible. The experimental machine most characterize xylem separation and debarking by frictional force between the bulges and Paper Mulberry by the drum rotation. It is possible automatically to operate the machine by controlling the temperature sensor and the time. Debarking process can be know that removed black outer layer has beem accumulate and measured the weight. The content of the extract, holocellulose, lignin and ashes of the white inner layer was analyzed. It is result that conditions of optimum process of the experimental machine is 45 RPM, temperature at $60^{\circ}C$(60 min.) and $80^{\circ}C$(60 min.), mixing bulge of 10 mm(120ea) and 30 mm(120ea) and capacity of Paper Mulberry 10 kg.

The Evaluation of the Temperature Characteristics at the Spendrels of Curtain wall with a-Si BIPV Window System (스팬드럴 부분 BIPV창호 적용 및 후면마감재 구성에 따른 온도특성 분석 연구)

  • Kim, Dong-Su;Oh, Myung-Hwan;Yoon, Jongl-Ho
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.165-170
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    • 2012
  • This study aims to analyze the characteristics of temperature variation of Spandrels. According to the change of SHGC of Window system, air space, insulation performance and absorption factor of inner surface at the Spandrels, It was firstly estimated by using simulation. Secondly, measured to minimize the temperature-rise of inner surface temperature and the intermediate air temperature by using Full-scale Mock-up based on the result of simulation analysis. As a result, it turns out that low SHGC window system such as BIPV system had an advantage of reducing the window surface temperature, and the surface temperature of clear window system was all higher than BIPV system on simulation results. In the experiment results, it had some advantages of increasing the Spandrels volume, decreasing insulation performance and lower absorption factor.

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Analysis of the Stedy and Unsteady Heat Conduction in the Cylinder Block Attached with Rectangular Fin (직사각형 휜이 부착된 실린더 블럭의 정상 및 비정상 열전도 해석)

  • 이건휘;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.5
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    • pp.1254-1263
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    • 1990
  • The temperature distribution and heat flux of the inner cylinder wall of a 4-cycle turbocharged gasoline engine were calculated by a 2-dimensional coordinate transformation. Boundary conditions of the inner wall of the cylinder were taken from the results of diagnostic engine simulations. Results show that the ununiformity of inner wall temperature of the cylinder black can be reduced by a proper choice of the thickness of fin and the distance between two cylinder blocks.

A Study on the Skin Improvement Effect of Castanea crenata Inner Shell with Microneedle Therapy System (미세다륜침을 이용한 율피의 피부개선 효과연구)

  • Koo, Jin Suk
    • The Korea Journal of Herbology
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    • v.37 no.2
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    • pp.23-31
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    • 2022
  • Objectives : The purpose of this research was to find out the efficacy of Castanea crenata Inner Shell (CCIS) on the skin by comparing the difference effect between only MTS (microneedle therapy system) and the CCIS essence application after MTS treatment. Methods : The present author performed once a week and total 3 times of MTS treatment. The treatment time took about 5 ~ 10 minutes and the depth of the needle was adjusted according to the participant's skin condition. In the control group, essence base was applied after MTS and in the experimental group, CCIS powder dissolved essence was applied. One week after each treatment, the change of skin condition was measured. Two weeks after the end of the clinical trial, the skin condition was checked again. Results : In the case of the test group and the control group, there was a significant decrease in thermography temperature and there was a significant increase in skin tone. In the case of pores and pigmentation, there was no significant difference on both group. In the case of moisture, there was a significant increase only in the test group. Conclusion : The MTS treatment itself showed good effects on thermography temperature and skin tone. But in the case of the moisture effect, it was much better when the CCIS essence was applied to the skin after MTS treatment. This study suggests that CCIS essence increases the efficacy of MTS on the point of moisture.

Environmental Factors and Catch Fluctuation of Set Net Grounds in the Coastal Waters of Yeosu (여수연안 정치망 어장의 환경요인과 어황 변동에 관한 연구)

  • 김동수
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.29 no.2
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    • pp.94-108
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    • 1993
  • In order to investigate the relation between the environmental properties and catch fluctuation of set net fishing ground located in the coastal waters of Yeosu, oceanographic observation and catches on the grounds were carried out from Jan. to Dec. in 1990 and 1992. The results obtained are summarized as follows; 1) Because of the surveyed area is a costal shallow water, the fishing ground was influenced largely by atmospheric phenomena such as air temperature. precipitation. etc. and so showed large variations in temperature and salinity yearly. The inner water flowed out mainly between Yeosu ad Namhe-do, and then through Kumo-do between Dolsan-do and Kumo-do. On the other hand, off shore water was supplied into the fishing ground from the vicinity of Sori-do and Yokchi-do. thus the fishing ground was occupied usually by various sources of water. 2) The water mass in the fishing ground were divided into the inner water(29.0~30.6$\textperthousand$) and the mixed water(31,7~32.2$\textperthousand$) and off shore water(32.3~32.8$\textperthousand$) accourding to the distribution of salinity from T-S diagram plotted all salinity data observed in 1990 and 1992. In summer the inner and mixing water which was formed by river flowed southerly and spread south-easterly in the vicinity of Kumo-do. The off shore water which supplied from the vicinity of Sori-do and Yokchi-do and inner water formed the thermal front and halo front in summer. 3) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel>Horse mackerel >Hair tail>Common mackerel> Sardine> Anchovy. The Catches of anchovy and sardine were high in April to May and those of hair tail and horse mackerel in July to September, but spanish mackerel were caught during the whole period of fishing. When inner water and mixing water appeared respectively and inner water and mixing water speared together in the set net fishing ground, the set net showed a high catch.

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Numerical Simulation on Hydrodynamic Characterization Changes Associated with the Construction of Dikes and Dredging Operations in Saemangeum Lake (새만금호 내 방수제 공사 및 준설에 의한 수리동역학적 특성 변화 수치 모델링)

  • Oh, Chan-Sung;Choi, Jung-Hoon;Cho, Young-Kweon
    • Journal of Environmental Science International
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    • v.22 no.9
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    • pp.1115-1129
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    • 2013
  • The study area is located on the western coast, and the inner development construction has been ongoing since 2011. The purposes of current study are to effectively simulate and quantitatively predict a temporal and spatial distributions of water temperature and salinity due to the stages of inner development construction in saemangeum reclaimed area. The transient-state numerical modeling using EFDC model is done, and the numerical simulation results are validated reasonably by repetitive numerical model calibration procedures with respect to field measurements of water temperature and salinity. The spatial distributions of water temperature and salinity show similar trends before and after construction of the dikes. In spring season, the salinity has maximum value of 21 psu, while, in summer season, the salinity shows 7 psu in a whole modeling domain. Thus, it is clearly observed that salt water is replaced by freshwater. However, the salinity and temperature reach their initial conditions at the end of the year. The salinity after construction of the dikes is lower than that before construction of them at Mankyeong area. On the other hands, after construction of the dikes, the salinity after dredging operations is higher than that before dredging. Because drastical increasing of water volume in Saemangeum Lake leads to increasing of stagnation time at bottom layer, and salt water is easily intruded to the two estuaries. Therefore, it may be concluded that hydrodynamic characteristics on Saemangeum are dominated by either Mankyeong and Dongjin discharge or sluice gates in/out-flow amounts, and thus they must be properly considered when rigorous and reasonable predictions of water temperature and salinity according to the stages of inner development construction.

A Study on the Performance Test and Verification of Heat Transfer characteristics in Automobile Rear Window Heater (자동차 후면 유리 열선의 열전달특성에 따른 성애제거 성능평가 및 성능검증 방법에 관한 연구)

  • Juen, H.Y.;Lee, C.K.;Bae, H.J.;Lee, S.J.
    • Journal of Power System Engineering
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    • v.9 no.2
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    • pp.73-80
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    • 2005
  • Both theoretical and experimental investigations were conducted to analyze defrosting behavior of a window heater operating in the low outdoor temperature($-20^{\circ}C$). To achieve this purpose, first a warm-chamber experiment($23^{\circ}C$) was performed to measure inner and outer surface temperature of the rear window(heated by the electric heater supplying 195 W) as functions of both time and position. Secondly, a cold chamber experiment was made to continuously record defrosting process of the frosted window. From the comparisons of the two experimental results, it was found that there was a similarity between the spatial distributions of both temperature and remaining frost. Thus, the temperature data from the warm-chamber experiments can be utilized to predict an expected zone covered with remaining frosts, and this approach can also be adopted in the inspection process in order to economically guarantee optimized performance of the window heater. Finally, an analytical model based on one-dimensional, steady-state heat transfer theories was proposed and successfully predicted the outer surface temperature of the rear window surrounded by cold air($-20^{\circ}C$) for the given operating conditions(heater power, inside and outside heat transfer coefficients, and surrounding air temperature, etc.).

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