• 제목/요약/키워드: Surface Water Temperature

검색결과 2,819건 처리시간 0.026초

온배수 방류시스템에 관한 기초적 연구 (A Study on the Discharge System of Thermal Waste Water)

  • 곽기수;전용호;김헌태;류청로;이경선
    • 한국해양공학회지
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    • 제21권6호
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    • pp.87-94
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    • 2007
  • This study used POM (Princeton ocean model) improved for applying to coastal area in order to predict the distribution of thermal waste water. This model was applied to the coastal circulation and the effect of thermal waste water of Cheonsu-Bay. So this study compared the discharge of thermal waste water with each layer and section. The tidal current was about 1.5 m/sec at surface level and 0.9 m/sec on bottom level at flood tide; tidal current was about 1.3 m/sec on surface level and 0.8 m/sec on bottom level at ebb tide. The method discharging the thermal waste water in the nearshore region (case 1) accelerates the diffusion of the thermal waste water in the north-south direction(longshore direction). However, the method discharge the thermal waster water in the offshore region (case 2) reduced the diffusion of the thermal waste water over the coastal region. According th the diffusion region of the thermal waste water with case 1 and case 2 at three different layers (surface, middle, bottom), the diffusion region by case 1 discharge method generally influenced wider region (twice) than the one by case 2 discharge method with lower temperature between $1^{\circ}C\;and\;2^{\circ}C$, whereas the case 2 discharge method influenced the deeper region (middle and botton layers) with higher change of the water temperature ($1{\sim}3^{\circ}C$).

반응 표면 분석방법을 이용한 쌀 압출 성형물 제조조건의 최적화 (Optimization for Extrusion Cooking Conditions of Rice Extrudate by Response Surface Methodology)

  • 이상현;김창근
    • 한국식품영양학회지
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    • 제7권2호
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    • pp.137-143
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    • 1994
  • To optimize extrusion cooking condition of single screw extuder for production of puffed rice extrudate using response surface methodology (RSM), moisture content, barrel temperature and screw speed were determined from contour maps, showing relationship between dependent (hardness, expansion ratio, water absorption index, water solubility Index, degree of gelatinization) and independent variables. Optimum operational conditions for production of puffed rice extrudate with suitable quality properties were moisture content 17%, barrel temperature 1$25^{\circ}C$ and screw speed 210 rpm, respectively.

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EXPERIMENTS ON THE INTERACTION OF WATER SPRAYS WITH POOL FIRES

  • Han, Yong-Shik;Kim, Myung-Bae;Shin, Hyun-Dong
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.518-525
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    • 1997
  • A series of measurements and visualization to investigate the interaction of water sprays with pool fires is presented. Fire source is a small-scale pool burner with methanol, ethanol and gasoline. Measurements of temperatures, $O_2$, $CO_2$, and CO concentrations along the plume centerline are carried out to observe pool fire structures without water sprays. Visualization by the Ar-ion laser sheet shows flow pattern of droplets of the sprays above the pool fires. It is observed that in the case of methanol and ethanol, water sprays continuously penetrate into the center of fuel surfaces. The gasoline pool fire allows intermittent penetration of water sprays because of pulsating characteristics of the gasoline flame. To evaluate the cooling effect of the fuel surface by the sprays, the temperature was measured at the fuel surface. As soon as the mists reach the fuel surface of methanol and ethanol, the temperatures of the fuel surface decrease rapidly below the boiling point, and then the fires are extinguished. Due to the application of mist upon the gasoline fire, though the fuel temperature decrease abruptly at the time of the injection, such a rapid decrease do not continue till the extinction point.

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콘크리트와 도막 방수층 계면에 발생되는 수증기압에 관한 실험적 연구 (An Experimental Study of Water Vapor Pressure that occurs at the Interface of a Fluid-Applied Membrane and Concrete)

  • 고진수;김문희;이성복;신윤호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.147-150
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    • 2006
  • Of the total defects that have occurred recently in the Korean construction market, over 30% are caused by the construction of defective waterproofing, and the phenomenon of air pockets in the waterproofing layer, which is caused by the concrete vapor pressure, is known to be the primary cause of defective waterproofing. Accordingly, in this study the theory about the relationship between water pressure and temperature as well as the damp-proofing volume of concrete and, then, the change of vapor pressure volume was measured and analyzed by making a test sample after spraying a dampness remover and a waterproofing material to a prepared test body. As a result of measuring the water vapor pressure for the surface temperature of the waterproofing layer with the fluid-applied membrane temperature based on about $10^{\circ}C$, which is the average temperature of Seoul, it was found that first, the fluid-applied membrane elevated up to about $40^{\circ}C$, and the water vapor pressure generated from the fluid-applied membrane was about $0.3kgf/cm^2$ when the surface temperature of the waterproofing layer was raised up to about $80^{\circ}C$. Second, when the fluid-applied membrane temperature of the waterproofing layer was raised from $30^{\circ}C\;to\;35^{\circ}C,\;about\;0.1kgf/cm^2$ of water vapor pressure was generated, and when supplying a thermal source to raise the fluid-applied membrane temperature of the waterproofing layer from $35^{\circ}C\;to\;40^{\circ}C$, approximately $0.05kgf/cm^2$ of water vapor pressure was generated.

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식물의 성장과 열화상카메라로 측정된 열적 특성과의 연관성 분석 (An Analysis of Relationships between Plant Growth and Temperature Characteristics Measured with Thermographic Camera)

  • 박상미;남다현;김지형;조건영;김하양;김정배
    • 한국태양에너지학회 논문집
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    • 제36권2호
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    • pp.1-7
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    • 2016
  • This study was experimentally performed to analyze the growth characteristics of a plant(wax tree or privet) using the surface temperature measured from thermal images captured using a thermal camera with water and cider. To do that, this study measured every each 12 hours the surface temperature and the stem temperature of leaves attached to the plant sample until the plants wilt on summer season in the laboratory room. From the experimental results, this study revealed that the temperature of front and back of the leaves is a little different due to the pore. The mean surface temperature of a leaf in cider is $0.52^{\circ}C$ higher than that of a leaf in water. The phenomena that the leaves of plants fall could be also demonstrated using the surface temperature. Before a leaf is falling from the tree, the temperature of the stem is lowered about $2^{\circ}C$ than those of other parts in a leaf. This result can be validated from previous result performed in University of Wisconsin.

자연순환형 태양열온수기 동파방지기술 (Freeze Protection for Passive Solar Water Heating System)

  • 김종현;홍희기;정재동
    • 설비공학논문집
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    • 제23권5호
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    • pp.327-333
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    • 2011
  • In the present work, a new freeze protection method has been proposed for a natural circulation system of solar water heater. Though electrothermal wire is popularly used for the purpose, there are freezing troubles by wire cut-off and shortage of excessive electric power consumption. In the experimental device, hot water in storage tank was used to heat the outlet pipe from the tank if the pipe surface temperature falls lower than a set point. The cold water pipe to the storage tank was installed to directly contact the hot water pipe surface temperature rose by transferred heat.

비등점의 가열 표면에서 나노유체 액적의 증발 특성 (Characteristics for Nanofluid Droplet Evaporation on Heated Surface at Boiling Temperature of Base Liquid)

  • 김대윤;정정열;이성혁
    • 한국분무공학회지
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    • 제20권4호
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    • pp.236-240
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    • 2015
  • This study aims to experimentally investigate the evaporation characteristics of nanofluid droplet on heated surface at boiling temperature of DI-water. In particular, textured surface was used to examine the effect of wettability on evaporation. At the initial stage of evaporation process, dynamic contact angle (DCA) of nanofluid droplet with 0.01 vol.% concentration on textured surface rapidly increased over its equilibrium contact angle by generated large bubble inside the droplet due to lower wettability. However, contact angle of nanofluid droplet with higher concentration on textured surface decreased with surface tension. In addition, total evaporation time of droplet on textured surface was considerably delayed due to reduction of contact area between droplet and solid surface. Thus, evaporation characteristics were highly affected by the nanofluid concentration and surface wettability.

액체 제습식 냉방 시스템의 최적 설계 (Optimization Design of Liquid Desiccant Cooling System)

  • 전동순;이상재;김선창;김영률;이창준
    • 설비공학논문집
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    • 제22권7호
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    • pp.419-428
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    • 2010
  • This paper presents the optimization process of liquid desiccant cooling system using LiCl aqueous solution as a working fluid. Operating conditions(mass flow rate, conditioner outlet concentration, difference concentration) and design factors for heat exchangers(difference temperature of the district heating water, leaving temperature difference of the conditioner, leaving temperature difference of the regenerator, air temperature difference of the conditioner, air temperature difference of the regenerator) were optimized by response surface method. As a result, we obtained the 7.297 kW of cooling capacity and 0.788 of COP at optimized condition. Effect of difference temperature of hot water on system performances was also examined. As difference temperature of the district heating water increases, the cooling capacity increases and COP decreases.

The Development Measuring System of Temperature Effect to Produce Electric Power of Solar Cell

  • Sadmai, Ong-art
    • International journal of advanced smart convergence
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    • 제4권1호
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    • pp.104-113
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    • 2015
  • This paper focuses on a temperature effects on a PV panel which has been installed in Thailand. The main objective is cleaning PV panels and reduce temperature of PV panel by water injects from waterway and experimental results of PV power what it is difference. This project is designed by PLC control system which water injects and control PV temperature, In addition, this project consists of hardware and software such as water pump, water injection and PLC control has been automatically and it can be control system manually. The automatic control system is working when PV temperature rises up over 45 degree Celsius after that the pumping machine would inject water to the surface of PV panels and it must be stop when the PV panel temperature comes down less than 45 degree Celsius. The result of actual experimental found that the control system has been done correctly under specify condition. The experimental has been shown electrical data before and after water injects on PV system found that the electrical power a bit increases and The energy has been taken from PV panel less than energy consumption equipment of control system which taken to operate the water injecting system.