Present Status of the KSTAR Superconducting Magnet System Development

keeman kim,A. Chertovskikh,B.S. Lim,C.S. Kim,D.J. Kim,D.K. Lee,G.S. Lee,H. Yonekawa,H.J. Lee,H.K. Park,I.S. Woo,J.S. Park,J.S. Kim,J.Y. Choi,K.P. Kim,K.R. Park,M.K. Kim,N.H. Song,S.H. Baek,S.I. Lee,S. 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.52

The mission of korea superconducting tokamak advanced research (KSTAR) Project is to develop a steady-state-capable advanced superconducting tokamak for establishing a scientic and technological basis for an attractive fusion reactor. Because the KSTAR mission includes the achievement of a steady-state-capable operation, the use of superconducting coils is an obvious choice for the magnet system. The KSTAR superconducting magnet system consists of 16 TF (toroidal eld) and 14 PF (poloidal eld) coils. Both of the TF and the PF coil systems use internally cooled cable-in-conduit conductors (CICC). The TF coil system provides a eld of 3.5 T at the plasma center, and the PF coil system is able to provide a ux swing of 17 V-sec. The major achievements in the KSTAR magnet system development include the development of CICC, the development of a full-size TF model coil, the development of a background magnetic eld generation coil system, and the construction of a large-scale superconducting magnet and CICC test facility. The TF and The PF coils are being fabricated for the KSTAR completion in the year 2005.

Conceptual design study of the K-DEMO magnet system

Kim, Keeman,Oh, Sangjun,Park, Jong Sung,Lee, Chulhee,Im, Kihak,Kim, Hyung Chan,Lee, Gyung-Su,Neilson, George,Brown, Thomas,Kessel, Charles,Titus, Peter,Zhai, Yuhu Elsevier 2015 Fusion engineering and design Vol.96 No.-

<P><B>Abstract</B></P> <P>As the ITER is being constructed, there is a growing anticipation for an earlier realization of fusion energy. A major design philosophy for the initiated conceptual design study for a steady-state Korean fusion demonstration reactor (K-DEMO) is engineering feasibility. A two-staged development plan is envisaged. K-DEMO is designed not only to demonstrate a net electricity generation and a self-sustained tritium cycle, but also to be used, in its initial stage, as a component test facility. Then, in its second stage, a major upgrade is carried out by replacing in-vessel components in order to show a net electricity generation on the order of 500MWe. After a thorough 0-D system analysis, the major radius and minor radius are chosen to be 6.8m and 2.1m, respectively. In order to minimize wave deflection, a top-launch high frequency (>200GHz) electron cyclotron current drive (ECCD) system will be the key system for the current profile control. For matching the high frequency ECCD, a high toroidal field (TF) is required and can be achieved by using high current density Nb<SUB>3</SUB>Sn superconducting conductor. The peak magnetic field reaches to 16T with the magnetic field at the plasma center above 7T. Key features of the K-DEMO magnet system include the use of two TF coil winding packs, each of a different conductor design, to reduce the construction cost and save the space for the magnet structure material.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Perform a preliminary conceptual study for a steady-state Korean DEMO reactor. </LI> <LI> Present a preliminary design of TF (toroidal field) magnet. </LI> <LI> Present a preliminary design of CS (central solenoid) magnet. </LI> <LI> Present a preliminary design of PF (toroidal field) magnet. </LI> </UL> </P>

(Review Article) Status of the KSTAR Project

KIM, Keeman,OH, Yeong-Kook,S. BAK, Joo,KWON, Myeun,LEE, Gyung-Su,KSTAR team, The 低溫工學協會 2006 低溫工學 Vol.41 No.5

<P>The KSTAR project was started in 1996 and conducted in three phases, the conceptual design phase (1996-1998), the R&D and engineering design phase (1998-2002), and the construction phase (2002-2007). The mission of the Korea Superconducting Tokamak Advanced Research (KSTAR) Project is to develop a steady-state-capable advanced superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Since the KSTAR mission includes the achievement of a steady-state-capable operation, the use of superconducting coils is an obvious choice for the magnet system and the long pulse current drive and heating systems are also the important aspect of the KSTAR design features. The advanced tokamak aspect of the mission is incorporated in the design features associated with flexible plasma shaping, double-null divertor and passive stabilizer, internal control coils. All the major components are in the stage of the fabrication and assembly for the completion of the KSTAR construction in the year 2007.</P>

[디젤엔진부문] NO Emission Characteristics in Counterflow Diffusion Flame of Blednded Fuel of H₂/CO₂/Ar

Jeong Park,KeeMan Lee,Tae Kwon Kim 한국자동차공학회 2000 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Flame structure and NO emission characteristics in counterflow diffusion flame of blended fuel of H₂/CO₂ /Ar have been numerically simulated with detailed chemistry. The combination of H₂ CO₂ and Ar as fuel is selected to clearly display the contribution of hydrocarbon products to flame structure and NO emission characteristics due to the breakdown of CO. Radiative heat loss term is involved to correctly describe the flame dynamics especially at low strain rates. The detailed chemistry adopts tile reaction mechanism of GRl2.11, which consists of 49 species and 279 elementary reactions. All mechanisms including thermal. NO₂ N₂O, and Fenimore are taken into account to separately evaluate the effects of Co, addition on NO emission characteristics. TIIC increase of added CO₂ quantity causes flame temperature to full since at high strain rates diluent effect is prevailuig and at low strain mtes the brcakdO\\I1 of CO, produces relatively populous hydrocarbon products and thus the existence of hydrocarbon products inhibits chain branching. It is also found that the contribution of NO production by N₂O and NO₂ mechanisms arc negligible and that thermal mechanism is concentrated on only the reaction zone. As strain rate and CO₂ quantity increase, NO production is remarkably augmented.

하이브리드 프랙탈의 형상 반복횟수에 따른 V자형 난류 화염 특성

김정현(JungHyun Kim),이기만(KeeMan Lee) 한국추진공학회 2022 한국추진공학회 학술대회논문집 Vol.2022 No.5

이중선회 가스터빈 모델 연소기에서 연소실 길이에 따른 화염 불안정 주파수 신호 특성

장문석(Munseok Jang),이기만(Keeman Lee) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.11

본 연구는 이중선회 가스터빈 연소기에서 연소 불안정성에 관한 연구이다. 연소기의 연소 불안정성은 압력변동 주파수와 열 방출 주파수 간의 상호작용에 의하여 발생하며, 큰 소음과 진동을 일으켜 연소기에 손상을 유발한다. 본 연구에서는 연소 불안정성을 규명하기 위하여 열용량과 연소실의 길이를 변경하여 가며 압력변동 주파수와 열 방출 주파수의 정보를 얻었고, 모든 조건에서 두 값이 일치하는 현상을 확인하였다. 그 결과 3kW~5kW 영역과 6kW~8kW의 영역이 서로 다른 경향을 나타내는 것을 확인 하였으며, 3kW~5kW영역에서 연소실 길이가 증가 하여도 그 값이 일정하게 유지되는 현상은 불규칙한 역화와 재점화로 인한 것이라 확인하였다. This parer described an experimental investigations of the unsteady in a dual swirl gas turbine combustor. Combustion instability of the combustor is caused by the interaction of the pressure fluctuation frequency and the heat release frequency, causing a big noise, vibration and causing damage to the combustor. In this study, in order to examine the combustion instability phenomenon of gas turbine combustor configuration, the information of heat release and pressure fluctuation period with respect to the variation in both thermal power and combustor length was collected experimentally. This phenomenon was confirmed that the two values match in all conditions. As a result 3kW ~ 5kW region and 6kW ~ 8kW region was confirmed that represent different trends, 3kW ~ 5kW region, also by increasing of combustion length is a phenomenon that its value remains constant due to the irregularities were confirmed will Flashback and re-ignite.

PLIF 및 자발광 계측을 이용한 이중선회 가스터빈 연소기에서 연소불안정 모드 연구

최인찬(Inchan Choi),이기만(Keeman Lee),Mrinal Juddoo,A.R. Masri 한국연소학회 2014 한국연소학회지 Vol.19 No.1

This paper described an experimental investigations of combustion instability mode in a lean premixed dual swirl combustor for micro-gasturbine system. When such the instability occurs, a strong coupling between pressure oscillations and unsteady heat release excites a self-sustained acoustic wave which results in a loud, annoyed sound and may also lead a structural damage to the combustion chamber. The detailed period of flame behavior and heat release in combustion instability mode have been examined with high speed OH and CH-PLIF system and CH<SUP>*</SUP> chemiluminescence measurement, flame tomography with operated at 10 ㎑ and 6 ㎑ each. Experiment results suggest that unstable flame behavior has a specific frequency with 200 ㎐ and this frequency is accords with about 1/2 sub-harmonic of combustor resonance frequency, not fundamental frequency. This is very interesting phenomenon that have not reported yet from other previous works. Therefore, when a thermo-acoustic instability with Rayleigh criterion occurs, the fact that the period of heat release and flame behavior are different each other was proposed for the first time through this work.

프랙탈 난류생성판을 갖는 V-shape 화염에서 난류 예혼합 화염 분석 : Part. Ⅲ 난류 연소속도

김주한(Juhan Kim),이기만(Keeman Lee) 한국연소학회 2021 한국연소학회지 Vol.26 No.4

This study focused on calculating the turbulent flame speed in a V-shape turbulent premixed flame using a circular fractal turbulence generator. In previous studies [Part. I turbulent flow characteristics in a Non-Reacting Field], [Part. II characteristics of turbulent flame structures], the non-reactive turbulent flow and turbulent flame structure for the V-shape flame of a fractal turbulence generator were investigated in detail. Two types of turbulent burning velocities are evaluated : local displacement and consumption speeds. The local consumption speed is calculated via the image processing of flame surface density. The results show that turbulent burning velocity increases much with fractal grids as compared with the conventional grids perforated plate and mesh. Finally, it was confirmed that the correlation between the turbulent flow factor and the two turbulent burning velocities of each turbulence generator was collapsed well with a specific correlation equation.

이중선회 가스터빈 모델 연소기에서 맥놀이 현상으로 인한 연소불안정 특성

장문석(Munseok Jang),이기만(Keeman Lee) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.5

본 연구는 이중선회 가스터빈 모델 연소기의 연소 불안정성에 관한 연구이다. 열용량과 연소실 길이를 변경하여 가며 실험을 진행하였고, 그 결과 단일 선회 연소기의 특성과 다른 특성이 발생하는 것을 확인하였다. 열용량이 3, 4, 5 kW에서 연소실 길이가 길어짐에 주파수의 값이 감소하지 않고 일정하게 나타났다. 이에 압력 신호와 화염의 거동을 확인한 결과 연소실길이가 짧을 때와 달리 길어졌을 때 맥놀이 현상이 발생하며, 화염의 거동이 파일럿 화염과 메인 화염이 각각 다른 주기로 거동함을 확인하였다. 즉 주파수 값이 일정하게 유지되는 원인은 맥놀이 현상 때문이라 판단된다. This research is the study of combustion instabilities in dual swirl gas turbine model combustor. An experiment is conducted by changing the thermal power and the combustor length in this study. As a result, it was confirmed that this characteristic is other tendency of the single swirl combustor. The value of the frequency was constant when the combustor length becomes more longer at thermal power 3, 4, 5 kW. So it was confirmed that the beating phenomenon occurs when combustor length was longer and pilot and main flame have different periods. The constant frequency was analyzed as the results of the beating phenomenon.

환형연소기에서 노즐 배치에 따른 안정성 감소 효과에 관한 연구

이희도(Huido Lee),이기만(Keeman Lee) 한국연소학회 2021 KOSCOSYMPOSIUM논문집 Vol.2021 No.11