• Title/Summary/Keyword: Gas Transport

Search Result 863, Processing Time 0.027 seconds

Opportunities and challenges of solar energy application in energy sector of Sri Lanka

  • De Silva, Kaluthanthiri Patabendi Sepali Darshika
    • Bulletin of the Korea Photovoltaic Society
    • /
    • v.6 no.1
    • /
    • pp.45-55
    • /
    • 2020
  • Although Sri Lanka's current carbon footprint is much less compared to other developing countries, the country's existing and planned economic developments have raised the demand for power, resulting an increased GHG (Greenhouse gas) emission. GHG in Sri Lanka is emitted mostly by the burning of fossil fuels for energy generation including transport. However, the most effective way of reducing GHG emissions from the energy sector is to use renewable energy sources. Solar is in the top list of renewable resources that has much potential to use to meet the demand for electricity generation in the country. The purpose of this study is to evaluate the current status of solar power generation and opportunities, barriers for implementing the programs of solar energy in Sri Lanka. Literature reviews mainly used as the primary tool for this study. Sri Lankan government had set the targets for adding 200 MW to the national grid by 2020, and to increase up to 1000 MW by 2025 of solar electricity. To achieve these targets the prevailing barriers have to be considered.

Effect of Operating Conditions on Characteristics of Combustion in the Pulverized Coal Combustor (미분탄 연소로의 운전조건이 연소특성에 미치는 영향)

  • Kang, Ihl-Man;Kim, Ho-Young
    • 한국연소학회:학술대회논문집
    • /
    • 1999.10a
    • /
    • pp.139-148
    • /
    • 1999
  • In oder to analyze the effect of operating conditions on pulverized coal combustion, a numerical study is conducted at the pulverized coal combustor. Eulerian approach is used for the gas phase, whereas Lagrangian approach is used for the particle phase. Turbulence is modeled using standard ${\kappa}-{\varepsilon}$ model. The description of species transport and combustion chemistry is based on the mixture fraction/probability density function(PDF) approach. Radiation is modeled using P-l model. The turbulent dispersion of particles is modeled using discrete random walk model. Swirl number of secondary air affects the flame front, particle residence time and carbon conversion. Primary/Secondary air mass ratio also affects the flame front but little affects the carbon conversion and particle residence time. Air-fuel ratio only affects the flame front due to lack of oxygen. Radiation strongly affects the flame front and gas temperature distribution because pulverized coal flame of high temperature is considered.

  • PDF

LCD 제조용 스퍼터링 장비의 비접촉식 유리평판 이송장치에 대한 수치적 연구

  • Gang, U-Jin;Im, Ik-Tae;Kim, U-Seung
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
    • /
    • 2007.06a
    • /
    • pp.149-156
    • /
    • 2007
  • Non-contact transportation of the large-sized glass plate using air-cushion is considered for sputtering system of LCD panel. The Argon gas from second gas injection holes is injected to levitate and transport the glass plate. Low maximum pressure and uniform pressure distribution on the bottom surface of the glass plate must be maintained for stable levitation and transportation of the glass plate. Therefore, the analysis of fluid flow between the glass plate and the air-pad is numerically performed for varying space between the injection holes in this study. The pressure uniformity on the bottom surface of the glass plate is evaluated for overall glass plate. The distance between the injection holes must be designed below 90 mm for obtaining the low maximum pressure and uniform pressure distribution.

  • PDF

The Crystallographic Properties of TiC Deposited on Different Substrate Steel by Chemical VaporDeposition (화학증착법에 의한 여러 가지 강들위에 증착된 TiC의 결정학적 특성)

  • 윤순길;김호기
    • Journal of the Korean Ceramic Society
    • /
    • v.24 no.6
    • /
    • pp.519-526
    • /
    • 1987
  • TiC was deposited onto several substrate steels by the Chemical Vapor Deposition technique from TiCl4-CH4-H2 gas mixtures in the horizontal resistance furnace. Deposition rates and morphologies of the coatings were investigated with the carbon contents. Deposition thickness increased linearly with the deposition time in the Presence of CH4 gas. The various interlayers of coating by EDS and X-ray Diffraction were proved as Cr7C3 and Fe3C. Chromium contents did not affect the preferred orientation of TiC deposit. The deposition was controlled by a mass transport and a surface reaction in case of 1 wt% C-5.25 wt% Cr steel irrespective of deposition temperature.

  • PDF

Energy Distribution Function for Electrons in $SF_6$+He mixtures gas used by MCS-BEq (MCS-BEq에 의한 $SF_6$-He 혼합기체의 에너지 분포함수)

  • Seong, Nak-Jin;Kim, Sang-Nam
    • Proceedings of the KIEE Conference
    • /
    • 2004.07e
    • /
    • pp.41-44
    • /
    • 2004
  • This paper describes the electron transport characteristics in $SF_6$-He gas calculated for range of E/N values from 50${\sim}$700[Td] by the Monte Carlo simulation(MCS) and Boltzmann equation(BEq) method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained by TOF method. The results gained that the values of the electron swarm parameters such as the electron drift velocity. the electron ionization or attachment coefficients. longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N.

  • PDF

Compressibility Factor Effect on the Turbulence Heat Transfer of Super-critical Carbon Dioxide by an Elliptic-blending Second Moment Closure (타원혼합모형을 이용한 초임계상태 이산화탄소의 압축성계수에 의한 난류열전달 특성)

  • Han, Seong-Ho;Seo, Jeong-Sik;Shin, Jung-Kun;Choi, Young-Don
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.31 no.1 s.256
    • /
    • pp.40-50
    • /
    • 2007
  • The present contribution describes the application of elliptic-blending second moment closure to predict the gas cooling process of turbulent super-critical carbon dioxide flow in a square cross-sectioned duct. The gas cooling process under super-critical state experiences a drastic change in thermodynamic and transport properties. Redistributive terms in the Reynolds stress and turbulent heat flux equations are modeled by an elliptic-blending second moment closure in order to represent strongly non-homogeneous effects produced by the presence of walls. The main feature of Durbin's elliptic relaxation second moment closure that accounts for the nonlocal character of pressure-velocity gradient correlation and the near-wall inhomogeneity guaranteed by the elliptic blending second moment closure.

The Optimization of AC-PDP Cell by 2D Simulations

  • Kim, Woong;Y.K. Shin;C.H. Shon;J.H. Kang;Park, J.S.;Lee, J.K.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 1999.07a
    • /
    • pp.227-227
    • /
    • 1999
  • Plasma display panel(PDP) is a leading technology for large-area flat panel displays. A current issue in operating the PDP cell is that the efficiency of the PDP cell is very low. To increase the efficiency of the PDP cell, the visible light needs to be maximized and the power consumption minimized. Since the excited xenons are related to the production of the visible light, it is important to optimize the cell geometry and the gas composition that produce the excited xenons more efficiently. A 2D-fluid code (FL2P) is developed and used to simulate the plasma dynamics and the radiation transport in the PDP cell. The cell is optimized with the code for various operating conditions and cell dimensions such as the voltage pulse, electrode length, electrode spacing, gap size, dielectric constant, gas mixture ratio, pressure, and pulse duration.

  • PDF

Re-determination of inelastic collision cross sections for $C_{3}F_{8}$ molecular gas in $C_{3}F_{8}-Ar$ mixture gases ($C_{3}F_{8}-Ar$혼합가스 상에서 $C_{3}F_{8}$분자가스의 비탄성단면적의 재결정)

  • Jeon, Byoung-Hoon
    • Proceedings of the KIEE Conference
    • /
    • 2005.11a
    • /
    • pp.21-23
    • /
    • 2005
  • The electron transport coefficients, the electron drift velocity W, the longitudinal diffusion coefficient $ND_L$ in $C_{3}F_{8}-Ar$ mixture gases were measured by Double shutter drift tube and calculated by multi-term approximation of the Boltzmann equation over the wide E/N range from 0.03 to 100 Td. And an inelastic collision cross sections for $C_{3}F_{8}$ molecular gas were redetermined for quantitative characteristic analysis.

  • PDF

Analysis of Recent Accidents and Regulating Activities for the Hazardous Materials in Korea

  • Kwon, Kyung-Ok;Kim, Young-Eun
    • Journal of the Korean Institute of Gas
    • /
    • v.15 no.1
    • /
    • pp.68-73
    • /
    • 2011
  • The systems in Korea regarding manufacture, storage, transport and use of hazardous materials are regulated by the related laws and ordinances. The number of accident from hazardous materials has recently decreased but the size of accident has increased according to the hazardous substances are greatly consumed and delivered. The results of analysis showed that most of accidents are caused by human problems and occurred frequently at unauthorized facilities. It is suggested that workers should be trained more and the strict regulation on unauthorized facilities is needed to reduce the accidents caused by hazardous materials.

HEAT TRANSFER ANALYSIS ON THE PREFORM HEATING AND THE GLASS FIBER DRAWING IN A GRAPHITE FURNACE FOR OPTICAL FIBER MANUFACTURING PROCESS (광섬유 생산공정용 퍼니스 내의 모재 가열 및 유리섬유 인출에 대한 열전달 해석)

  • Kim, K.;Kim, D.;Kwak, H.S.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.88-91
    • /
    • 2011
  • Glass fiber drawing from a silica preform is one of the most important processes in optical fiber manufacturing. High purify silica preform of cylindrical shape is fed into the graphite furnace, and then a very thin glass fiber of 125 micron diameter is drawn from the softened and heated preform. A computational analysis is performed to investigate the heat transfer characteristics of preform heating and the glass fiber drawing in the furnace. In addition to the dominant radiative heating of preform by the heating element in the furnace, present analysis also includes the convective heat transport by the gas flowing around the preform that experiences neck-dawn profile and the freshly drawn glass fiber at high fiber drawing speed. The computational results present the effects of gas flow on the temperature of preform and glass fiber as well as the neck-down profile of preform.

  • PDF