• Title, Summary, Keyword: Thermal Discharge

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Application of Thermal Discharge Dispersion Model on Cheonsu Bay (천수만 해역에서 온배수 확산모델의 적용)

  • 박영기
    • Journal of Environmental Science International
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    • v.4 no.2
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    • pp.169-180
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    • 1995
  • This Daper presents effective simulation of the dispersion of thermal discharge which can be relesed at Boryong power plant. Applied numerical models are finite difference method for hydrodynamic analysis and Masch-model comprised of conditions for ambient current velocity. Application of these models is done in Cheonsu Bay Summing up the results of this study are as follows; 1. It is found that the result for measurements of temperature appears high at southwardly Songdo on flood. The reason is that tidal currents which flowed north direction were accompanied with southwardly dispersed thermal discharge. A minute Particle of thermal Plume has a tendency to dispels inward Deacheon Bay. 2. According to the results of numerical experiment, maximum distance for thermal discharge dispersion appeared 10.8 km at lower part and 8.6 km at upper part with power plant outlet as starting point. 3. Comparative the numerical simulation and Airbone Multispectral Scanner indicated that thermal discharge should be verified separative phenomena. The simulated results were compared with field data set showing good agreement. It is concluded that these model can be simulated well.

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Partial Discharge Diagnosis of Thermal Degradated PVC Cable (열열화된 PVC 케이블의 부분방전 진단)

  • Song, Ki-Tae;Lee, Sung-Ill
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.3
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    • pp.208-214
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    • 2011
  • In this thesis, the partial discharge according to applied voltage and variations of cross-sectional area and length of the conductor related to general condition for using cable was measured in order to study degradation diagnosis for 2-Core cable of the PVC insulator used in industrial fields for other safety installations. Also the thermal degradation conditions under various installation circumstances of cables were studied by assuming degradation conditions with each different degradation rate (50%, 67%, 100%) such as variation in degradated temperature, thermal exposure time, normal state, partially degradated state and overall degradated state for thermal degradation diagnosis. The quantity of electric discharge (V-Q) according to applied voltage was measured for measurement of inception voltage and extinction voltage. The quantity of electric discharge and the number of electric discharge (Q-N) were measured with applied voltage kept constantly. In addition, pictures were taken using SEM (scanning electron microscope) to compare the surface of external insulator to degradated state of internal insulator according to thermal degradation temperature and also compare the surface of external insulator to degradated surface state of internal insulator according exposure time of cables to thermal stress.

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

  • Kwak, Ki-Su;Jeon, Yong-Ho;Kim, Heon-Tae;Ryu, Cheong-Ro;Lee, Kyung-Seon
    • Journal of Ocean Engineering and Technology
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    • v.21 no.6
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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 ($1{\sim}3^{\circ}C$).

Spectral analysis for thermal discharge of Hadong Power Plant (하동화력 발전소 온배수에 대한 Spectrum 분석)

  • Park, Il-Heum;Lee, Geun-Hyo
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • pp.435-440
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    • 2006
  • In order to understand changes of water temperature for thermal discharge of Hadong power plant in Gwangyang and Jinju Bay, it was analyzed for temperature data of representative season by MEM(Maximum entropy method) that is one of the spectral analysises. And due to understand effect of thermal discharge at each point, analyzed spectral data showed reactive energy rate of reference point by calculating energy from 24 time period to height frequency zone. As a result of spectral analysis, it showed that there were 9 points which are largely effected, 7 points which will be estimated, 6 points which is difficult to estimate, 14 points which rarely effected by thermal discharge.

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Spatial Variation in Macrobenthic Communities Affected by the Thermal Discharge Volumes of a Nuclear Power Plant on the East Coast of Korea (원자력 발전소의 온배수 배출량 변화에 따른 대형저서동물 군집의 공간 변화)

  • Yu, Ok Hwan;Lee, Hyung-Gon;Lee, Jae-Hac;Kim, Kyung-Tae;Myung, Cheol-Soo;Moon, Hyung Tae;Byun, Ju Young
    • Ocean and Polar Research
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    • v.35 no.4
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    • pp.299-312
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    • 2013
  • This study analyzed the species composition and density of a macrobenthic community according to variations in the thermal discharge volumes of a nuclear power plant before, during, and after the shutdown of the nuclear power plant during two periods. In this study, 369 macrobenthic fauna species were collected, and their mean density was 1,712 ind. $m^{-2}$. The number of species and diversity of macrobenthic fauna decreased with distance from the thermal discharge area, regardless of whether the nuclear plant shutdown or not. Many macrobenthic taxa appeared near the thermal discharge area, but polychaetes species were more prominent in outer areas than at the discharge area. The density of macrobenthic fauna decreased with distance from the thermal discharge area during a plant shutdown in the fall of 2011, but increased, except at two sites, near the discharge area in the winter of 2012. Cluster analysis indicated that the spatial distribution of the macrobenthic community changed in areas near the nuclear power plant after a shutdown period; that is, the station group I, in areas near the nuclear power plant, became narrower after the shutdown, but it recovered to previously occupied areas after the nuclear power plant began operating again. Opportunistic species, such as the polychaetes Lumbrineris longifolia (= Scoletoma longifolia) and Mediomastus californiensis, which were present in high densities near thermal discharge areas, decreased after the shutdown but recovered after the plant re-opened. The number of species and diversity of the macrofauna and the density of dominant species showed a significant correlation with temperature, except in winter periods. The results of this study revealed that changes in the amount of thermal discharge before and after the shutdown of a nuclear power plant could exert an influence on the structure of macrobenthic community within the thermal discharge areas depending on the season.

A Study on the NOx Removal Rate by Arrangement of Discharge Electrode in Pulsed Corona Discharge Reactor (펄스 코로나 반응기에서 방전극의 배열에 따른 탈질율 연구)

  • Choi, Min;Park, So-Jin;Wi, Young-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.3
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    • pp.315-323
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    • 2003
  • The goal of this study if the optimization of discharge electrode for pulsed corona discharge reactor located in thermal power plant. For this purpose, we have performed experiments of NO$_{x}$ removal rate by exchange of discharge electrode diameter and arrangement of discharge electrode in the non -thermal plasma reaction facility using a ethylene as additive. If the diameter and numbers of discharge electrode were larger, the NO$_{x}$ removal rate was higher. From these results, if we optimized the shape and installed numbers of discharge electrode at the pilot plant, we could increase the NO$_{x}$ removal rate with less amount of additive than current amount.mount.

Gasification from Surface during Discharge and Thermal Processes in Plasma Display Panel (PDP)

  • Soh, Hyun;Lee, Sang-Moo;Kim, Young-Chai
    • 한국정보디스플레이학회:학술대회논문집
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    • pp.495-498
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    • 2004
  • PDP use the mixture of inert gases to generate a discharge inside display pixels. Inside of PDP, there exist highly reactive conditions in the gap between two glass panels. MgO layer and phosphor have been investigated as a function of discharge and thermal process. Impurities such as CO, $CO_2$, OH and $H_2O$ in discharge region may deteriorate the characteristics of PDP operation during life time. Change of impurity generation of various MgO and phosphor surfaces were measured by using x-ray photoelectron spectroscopy(XPS) and quadropole mass spectrometer (QMS). Carbon containing species such as C, CO and $CO_2$ were drastically increased on the surfaces during discharge and thermal treatment. Carbon impurities on the MgO and phosphor are the dominant factor for their instability.

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A Study of Discharge Coefficient for Thermal Buoyancy Natural Ventilation (온도차 자연환기 이론의 유량계수에 대한 연구)

  • Shin, Dongshin;Ko, Hyunjun;Kim, Sehyung;Seon, Jihyung;Yoon, Sangmin;Lee, Jinyoung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.12
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    • pp.639-644
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    • 2015
  • This study reviews the discharge coefficient for thermal buoyancy natural ventilation through experimentation. We measure the air velocity at the outlet, which is needed to derive the discharge coefficient and to compare with the theoretical value. When a temperature difference exists between the inside and outside of the building, the measured discharge coefficient differs from the theoretical value with a maximum difference of 12%. The size and position of the openings have little effect on the discharge coefficient. For practical application, the theoretical discharge coefficient can be used with little modification.

Considerations on the Long-term Reliability of On-line Partial Discharge Ceramic Sensor for Thermal Power Generators and its Demonstration in the Field

  • Sun, Jong-Ho;Youn, Young-Woo;Hwang, Don-Ha;Kang, Dong-Sik
    • Journal of Electrical Engineering and Technology
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    • v.7 no.1
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    • pp.103-108
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    • 2012
  • The present study describes the considerations on the long-term reliability of the on-line partial discharge (PD) ceramic sensor for thermal power generators. Voltage acceleration aging tests were carried out under continuous and impulsive thermal aging at more than $100^{\circ}C$, considering the practical service environment. Experimental results show that the sensors have a life that could last for more than 100 years, excellent dielectric characteristics, and insulation strength. In addition, the ceramic on-line PD sensors were installed in a thermal power generator in Korea for demonstration. The results of the PD calibration and test voltage application prove that the on-line ceramic sensors have satisfactory performances for on-line PD measurement.

Use of Speckle Pattern for Monitoring Thermal Energy Behavior of Battery Cathode

  • Kim, Byungwhan;Jang, Junyoung
    • Journal of the Optical Society of Korea
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    • v.20 no.3
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    • pp.396-400
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    • 2016
  • Laser speckle patterns were used to monitor variations of thermal voltages of a cathode during a battery discharge. Discharge voltages measured with an oscilloscope were utilized as a figure of merit of thermal voltages in Zn metal. Using an optical imaging system, speckle patterns were taken for zinc metal surface over a time period of 3 minutes. Pixel sum distribution functions (PSDFs) were extracted from speckle patterns. Accumulated pixel sums quantified from PSDFs over an optimized grayscale range strongly correlated with discharge voltages. This suggested that dark matter or particles may have the capability of both absorbing and radiating thermal energies simultaneously. The black body-like properties were able to be validated by identifying coincidences with distinct features of a black body spectrum. The pixels belonging to the grayscale range were confirmed to represent dark matter of a speckle pattern. It was clear that dark matter was part of surface plasmon carriers. The proposed sensing system can be applied to monitor thermal energy variations in any material.