http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Non-IP 장치 제어를 위한 새로운 UPnP 브리지 구조
강정석(JeongSeok Kang),최용순(YongSoon Choi),김성훈(SeongHoon Kim),이광국(KwangKoog Lee),박홍석(HongSeong Park) 대한전기학회 2007 대한전기학회 학술대회 논문집 Vol.2007 No.4
This paper presents an architecture of UPnP Bridge that allows controlling Non-iP devices from UPnP control point, without modification to Non-IP device or UPnP control point implementations. UPnP devices must provide SSDP discovery, SOAP control and GENA event processes. To represent Non-IP devices to UPnP devices, UPnP Bridge provides these functionalities on behalf of Non-IP devices. We provides two method to interoperability between UPnP and Non-lP devices, Message Field Description, Non-UPnP Proxy devices. And solution to integrate heterogeneous networking standards (RS232C, CAN, IEEE1394, USB) is provided.
초임계 환경에서 압력에 따른 와류형 분사기의 극저온 질소 분무 동적특성 수치적 연구
강정석(Jeongseok Kang),허준영(Junyoung Heo),성홍계(Hong-gye Sung),윤영빈(Youngbin Yoon) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.11
초임계 환경에서 작동하는 와류형 분사기의 극저온 실유체 분무 특성을 3차원 LES 수치기법을 적용하여 연구하였다. 초임계 상태방정식은 SRK(Soave-Redlich-Kwong) 상태방정식을 적용하였다. 질소로 채워진 챔버에 5bar의 차압으로 질소를 분무하여 50bar 조건에 대하여 실험결과와 수치해석 결과를 비교하여 검증하였다. 그리고 50bar조건과 70bar 조건에 대하여 분무각, 밀도, 속도를 비교하여 압력에 따른 차이를 분석하였으며 분사기 내 외부에서 발생하는 주파수의 변화와 분사기 외부에서 나타나는 동적 불안정파가 내부로 전파되는 현상에 대해 조사하였다. cryogen spray characteristics of a nitrogen swirl injector operating in supercritical environment have been numerically investigated. Turbulent numerical model is based on LES with real-fluid transport and thermodynamics over the entire pressure range; SRK equation of state. By injecting the nitrogen with 5 bar differential pressure to chamber filled with nitrogen, numerical result is validated by comparing with experimental result with respect to spreading angle under 50bar. Spray angle, density, velocity were analyzed at 50bar and 70bar pressure. The variation of frequency inside and outside the injector and dynamic wave propagation into the injector were investigated.
POD와 DMD를 이용한 와류형 분사기의 극저온 질소 분무 동적 특성 분석
강정석(Jeongseok Kang),성홍계(Hong-Gye Sung),손채훈(Chae Hoon Sohn) 한국추진공학회 2017 한국추진공학회지 Vol.21 No.5
The cryogenic nitrogen spray of a swirl injector has been numerically investigated using three dimensional LES turbulence model to analyze the dynamic characteristics under supercritical condition. To predict the precise nitrogen properties under supercritical condition, SRK equation of state, Chung’s method for viscosity and thermal conductivity and Takahashi’s correlation based on Fuller’s theory for diffusion coefficient are implemented. The complex flow structures due to interaction between flow field and acoustic field are observed inside and outside the injector under supercritical condition. FFT, POD, and DMD techniques are employed to understand the coherent structures. By implementing the FFT, the dominant frequencies are identified inside and outside the injector. The coherent flow structures related to the dominant frequencies are visualized using the POD and DMD techniques. In addition, the DMD provides the damping coefficient which is related with the instability prediction.
준 일차원 다상 반응유동 기법을 이용한 케로신/과산화수소 액체 핀틀 추력기 성능해석 연구: Part I. 주요 구성 모델 검증
강정석(Jeongseok Kang),복장한(Janghan Bok),성홍계(Hong-Gye Sung),권민찬(Minchan Kwon),허준영(JunYoung Heo) 한국추진공학회 2020 한국추진공학회지 Vol.24 No.6
A quasi one-dimensional multi-phase reaction flow analysis code is developed for the performance analysis of liquid pintle thrusters. Unsteady flow field, droplet evaporation, finite reaction and film cooling models are composed as the major models of the performance analysis. The droplet vaporization takes account of Abramzon’s vaporization model, and the combustion employs a flamelet model based on detail chemical reactions. Shine’s model is applied for the film cooling calculation. To verify each model, the Sod shock tube, single droplet vaporization, kerosene droplets combustion, and film length are evaluated.
준 일차원 다상 반응유동 기법을 이용한 케로신/과산화수소 액체 핀틀 추력기 성능해석 연구: Part II 추력기 성능 특성
강정석(Jeongseok Kang),복장한(Janghan Bok),성홍계(Hong-Gye Sung),권민찬(Minchan Kwon),허준영(JunYoung Heo) 한국추진공학회 2020 한국추진공학회지 Vol.24 No.6
The performance of pintle thruster is analyzed by using the pintle thruster performance analysis model which integrating the element models introduced in Part I. To verify the performance analysis, the results of the developed program are compared with the experimental data of kerosene/hydrogen peroxide liquid pintle thrusters. Based on the results, the characteristics of the pintle thruster are analyzed. The sensitivity analysis is performed to investigate the effect of thruster shape and operation parameters on performance characteristics using both OAT and scatter plot methods. The four performance parameters such as droplet diameter, film flow rate, O/F ratio, and nozzle throat diameter are evaluated to investigate their effects on characteristic speed, combustor pressure, and specific thrust.
VOF와 FSI 방법을 적용한 CBT 연소 정밀 모델링 및 해석
강정석(Jeongseok Kang),박종근(Jonggeun Park),성홍계(Hong-Gye Sung) 한국추진공학회 2022 한국추진공학회지 Vol.26 No.5
Precise modeling and analysis of closed bomb test(CBT) combustion using solid propellants was performed. The fluid structure interaction(FSI) method was implemented to analyze the gas and solid phases at the same time. The Eulerian analysis method was applied for the gas phase and grain combustion, and the Lagrangian analysis method was implemented for the grain movement. The interaction between the solid phase grains and the combustion gas was fully coupled through the source term. The volume of fluid(VOF) method was used to simulate the burning distance of the grain and the movement of the combustion surface. The force acting on the grain was comprised of the pressure and gravity acting on the grain burning surface, and the grain burning rate and grain movement speed were considered in the velocity term of the VOF. The combustion analysis was performed for both one and three grains, and fairly compared with the experiments. The acoustic field during grain combustion due to pressure fluctuations was also analyzed.