http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김주완(Juwan Kim),정영석(Youngsuk Jung),박광근(Kwangkun Park),조기주(Kie-Joo Cho),오승협(Seung-Hyub Oh) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.11
발사체의 추진제탱크 가압 방식에는 여러 가지가 존재한다. 한국형발사체의 경우 저온 헬륨을 가열하여 추진제탱크를 가압하는 방식을 사용한다. 이러한 저온 헬륨을 이용한 가압 방식은 가압가스와 추진제 간의 반응성이 낮고, 무게를 줄일 수 있으며, 재점화가 가능하다는 장점을 지니고 있다. 저온 헬륨은 발사 준비 과정 동안 충전이 되고, 발사 취소 시에 배출된다. 본 논문에서는 이러한 저온 헬륨 충전/배출 과정을 해석하였다. 해석 결과 총 충전 시간은 1, 2, 3단 각각 2400, 1300, 520초이다. There are several methods of propulsion tank pressurization in launch vehicle. In KSLV-II, cold helium is used for pressurization of propulsion tank. The advantages of cold helium pressurization system are chemical nonreactive, weightless, restartable etc. Cold helium is charged during launch operation and discharged during launch abort. In this paper, the process of cold helium charging/discharging is analyzed. The total charging times of cold helium are about 2400, 1300 and 520 sec respectively, 1<SUP>st</SUP>, 2<SUP>nd</SUP> and 3<SUP>rd</SUP> stage.
나노 구조물을 이용한 농도 차 발전 시스템에 관한 연구
김주완(Juwan Kim),김동권(Dong-Kwon Kim),김성진(Sung Jin Kim) 대한설비공학회 2012 대한설비공학회 학술발표대회논문집 Vol.2012 No.6
Ion selective alumina membranes and silica-coated membranes are studied to generate electric power from a concentration gradient by reverse electrodialysis. The surface in alumina membranes is usually positively charged when contacting an electrolyte. In alumina membranes, pore interior has higher positive ions than negative ions. On the other hand, the surface in alumina membranes with silica coating is usually negatively charged when contacting an electrolyte. Consequently, alumina membranes are ionic selective for positive ions and silica-coated membranes are ionic selective for negative ions. It is much easier to manufacture the porous membranes than ion exchange membranes. When an electrolyte concentration gradient is applied between the membranes, electric power is generated. Experimental investigation is conducted for the power generation from these alumina membranes and silica-coated membranes placed between two sodium chloride solutions with constant concentration ratio. Ion selectivity of alumina membranes and silica-coated membranes is constant as concentrations of the solutions increase. Due to relatively easy and low cost fabrication processing of alumina membranes, power generation from concentration gradients with alumina membranes could be widely used in a various application area.
김주완(Juwan Kim),임세영(S. Im) 대한기계학회 2002 대한기계학회 춘추학술대회 Vol.2002 No.3
We propose an implicit numerical implementation for Leblond's transformation plasticity constitutive equations, which are widely used in welded steel structure. We apply Euler backward scheme rule to integrate the equations and determine the consistent tangent modulus. The implementation may be used with updated Lagrangian formulation. we test a simple butt-welding process to compare with SYSWELD and discuss the accuracy. We study the efficiency of parallel computation for the finite element analysis of a welded structure using multi-frontal solver.