• 제목/요약/키워드: KIER

Search Result 540, Processing Time 0.027 seconds

Numerical Study on Thermal Characteristics at Absorber Plate of Flat-Plate Solar Collector with Single Riser (평판형 집열기의 단일 지관에서의 입구 Re수에 따른 흡열판 온도분포에 대한수치해석 연구)

  • Kim, Jeong-Bae;Lee, Dong-Won;Baek, Nam-Choon
    • Journal of the Korean Solar Energy Society
    • /
    • v.27 no.3
    • /
    • pp.149-154
    • /
    • 2007
  • It is essential to know the heat transfer characteristics at the absorber plate of Flat-plate solar collector for optimum design. For flat-plate solar collector, it is difficult to experimentally study the effect for the Reynolds number of riser considering low mass flow rate being applied into the collector with one riser tube. So, this study were performed to show the heat transfer characteristics of flat-plate solar collector with single absorber plate and riser for various Reynolds number at riser using commercial code FLUENT 6.0. The base collector size is chosen with $0.4m^2$ as 0.2m by 2m with single riser in this study, Reynolds number at riser is from 200 to 1200 including about 530 at typical flat-plate collector with 10 risers considering the mass flow rate of 0.02kg/s per collector area for the certificate test Through the simulation, the results were presented as the temperature distribution at the absorber plate for various flow rate and solar irradiance conditions, then showed the effective length scale of the absorber plate The real solar irradiation condition is assumed as the constant heat flux condition of $500w/m^2$ considering the annual average solar irradiance in Korea.

Application of IDL for Establishing the Database and Visualization System of National Wind Map (국가바람지도 데이터베이스화 및 가시화를 위한 IDL 활용)

  • Kim, Hyun-Goo;Lee, Soon-Hwan;Lee, Sang-Woo;Lee, Jong-Hyuk
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.06a
    • /
    • pp.185.2-185.2
    • /
    • 2010
  • 한반도 국가바람지도(김현구, 2009)는 한국에너지기술연구원에서 지식경제부의 부처임무사업으로 구축되었으며 현재 웹서비스(http://www.kier-wind.org)를 통하여 정보를 제공하고 있다. 국가바람지도는 수치기상예측(NWP; Numerical Weather Prediction) 모델을 이용하여 영토, 영해에 대해 $1km{\times}1km$의 고해상도로 작성한 뒤(이순환 등, 2009) 풍력자원 정보로 재가공되었다. 한반도 국가바람지도는 5년의 장기간에 대한 시계열 수치기상예측에 의하여 구축되었기 때문에 데이터베이스(DB; database)의 효율적 관리가 필연적으로 요구된다. MM5 또는 WRF 모델의 고유 출력포맷의 자료구조는 풍력자원분석에 필요한 기상요소 외에도 대기과학자에게 필요한 수많은 기상인자를 종합적으로 포함하고 있다. 따라서 2차원 층(layer) 또는 3차원 공간분포 분석 및 계산격자인 셀(cell)에서의 1차원 시계열 분석 등 다양한 자료축출에는 비효율적인 자료구조가 된다. 이러한 자료구조의 불편을 해소하기 위해서는 기상요소별로 독립적이고 빈번한 시계열 자료 추출에 효율성을 가지며 어떤 프로그래밍 언어를 사용하든지 직관적으로 쉽게 사용할 수 있는 바람지도 데이터베이스의 재구성이 요구된다. 이에 대용량 수치자료의 처리 측면에서 장점을 가지는 과학기술 프로그래밍 언어인 IDL을 기반으로 국가바람지도의 자료구조를 효율화하여 데이터베이스화 하였으며 IDL에 내재된 그래픽 기능을 활용하여 가시화를 구현함으로써 연구개발자의 입장에서 국가바람지도의 활용성 및 효율성을 향상시키고자 하였다.

  • PDF

Comparing the actual heating energy with calculated energy by the amended standard building energy rating system for apartment buildings (건축물에너지효율등급 평가프로그램에 의한 공동주택 난방에너지 소요량과 실제 사용량 비교)

  • Lee, A-Ram;Kim, Jeong-Gook;Kim, Jong-Hun;Jeong, Hak-Geun;Jang, Cheol-Yong;Song, Kyoo-Dong
    • KIEAE Journal
    • /
    • v.15 no.2
    • /
    • pp.103-107
    • /
    • 2015
  • Purpose: Since September 1st, 2013, subjects of the evaluation have been expanded, and the evaluation standard has been detailed to enable Building energy rating system for all buildings. Accordingly, the new evaluation program (ECO2) has been developed, and therefore, apartment applied after September 1st, 2013 were evaluated with the new evaluation program. Therefore, this research suggests the improvement plan to figure out reasons for the evaluation result calculation and to calculate the evaluation results close to the actual energy usage by analyzing and comparing primary energy consumption as a result of the new evaluation program (ECO2) and actual heating energy usage on the same building. Method: When comparing evaluation results of the new evaluation program (ECO2) and actual heating energy usage, the tendency was similar but different. Also when comparing seasonally, the tendency was similar, but the different between actual heating energy usage and primary energy consumption during winter is greater than during spring or fall, and when comparing seasonal electric usage, heating alternatives were used through increased electrical usage during winter compared to during spring or fall. Result: Therefore, when evaluating apartment with the new program (ECO2) in the future, evaluation items relevant to the use of heating alternatives should be added, and the modification factor should be added according to the region. Based on the evaluation results of the research and actual energy usage, the Modification factors of the central part and the southern part were calculated respectively as 0.5 and 0.8.

Mobile Energy Shelter House(MeSH) for victims when a disaster occurs - Focused on Indoor Thermal Environmental Performance - (재난·재해 시 이재민을 위한 이동형 에너지 셜터하우스 (MeSH) 계획 -실내 온열환경 성능을 중심으로-)

  • Shin, Hwayeon;Kim, Jeonggook;Kim, Jonghun;Jeong, Hakgeun;Jang, Cheolyong;Hong, Wonhwa
    • KIEAE Journal
    • /
    • v.14 no.6
    • /
    • pp.75-80
    • /
    • 2014
  • Development of temporary housing for victims whose house damaged is required. In this study is to plan temporary house space 'Mobile Energy Shelter House ; MeSH' that can be inhabited for a long time. And measure the indoor Environmental performance. 'Mobile Energy Shelter House : MeSH' was made by reflecting Passive Design, Universal Design. Also, thermal insulation that meets the 'Korea standard insulation' for use low energy. Winter season, measuring temperature, humidity, air velocity and radiation temperature when floor heating that temperature controllers ware installed is used. Confirmed the data for the 8:00pm to 8:00am because evening hours are expected as residents live. Average outdoor temperature was $-11.3^{\circ}C$ and Indoor temperature was from $16.09^{\circ}C$ to $20.63^{\circ}C$. Calculated the TDRi of the window surface for checked condensation risk. TDRi value was 0.185. Furthermore, PMV value was -0.08 to -0.85. It was satisfied to ISO comfort criterion ranged.

Preparation and Electrical Conductivity of Scandia Stabilized Zirconia by using Ultrasonic Spray Pyrolysis (초음파 분무 열분해법을 이용한 스칸디아 안정화 지르니코니아의 제조와 전기 전도도)

  • Choi, Young-Hoon;Peck, Dong-Hyun;Park, Young-Chul;Lim, Kyoung-Tae;Suhr, Dong-Soo;Wackerl, J.;Markus, T.
    • Journal of the Korean Ceramic Society
    • /
    • v.44 no.12
    • /
    • pp.690-695
    • /
    • 2007
  • Scandia stabilized zirconia (ScSZ) is adapted for electrolyte material of solid oxide fuel cell (SOFC) because of its high ionic conductivity and chemical stability. ScMnSZ1 powder having a composition of $((ZrO_2)_{0.89}(Sc_2O_3)_{0.1}(MnO_2)_{0.01})$ is synthesized by ultrasonic spray pyrolysis (USP) method. Porous ScMnSZ1 powder is obtained by using a pore forming agent. Microstructure and morphology, particle size distribution of porous powder synthesized with 3wt% pore forming agent are investigated. Sintered ScMnSZ1 sample with ground fine powder are also investigated their microstructure and electrical conductivity. The electrical conductivity of sintered ScMnSZ1 samples with ground fine powder was 0.082 S/cm, 0.127 S/cm and 0.249 S/cm at $750^{\circ}C$, $800^{\circ}C$ and $900^{\circ}C$, respectively.