http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
판형열교환기 Chevron각 변화에 따른 유동현상 수치해석
정효민(Hyomin Jeong),김성수(SeongSoo Kim),정한식(HanShik Cheng),전유신(YouSin Chun),최현근(HyunGun Choi) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.4
Numerical analysis was carried out to examine the heat transfer and pressure drop characteristics of Plate Heat Exchanger(PHE) for absorption using Computational Fluid Dynamics(CFD) techniques. The Thermal performance and pressure drop are investigated. The computational model is a tree-dimensional narrow channel with angled triangular undulations. Geometric condition of PHE was port size 25㎜, channel plates area 3,465 ㎟. The main operating conditions in PHE, were taken a various Reynolds munber(from 1000 to 8000). The optimum flow pattern were presented with variation of pressure drop.
정효민(Hyomin Jeong),신용한(Yonghan Shin),사이드(S.M. Sayeed Bin Asad),박진관(Chenkuan Park),정한식(Hanshik Chung) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.4
LNG(Liquified Natural Gas) must be vaporized to be used as fuel in the industries, home application and soon. The cold energy generated about latent heat of 120 ㎉/㎏ and 80 kca/㎏ of sensible heat, while the vaporization process. Because air type vaporizer can't effect its vaporization performance properly due to the condensation of moisture in air outside the vaporization of moisture in air outside the vaporizer, 2~3 vaporizers are used alternately. To prevent freezing on the surface of vaporizer and solve the low performance, The heating source of gasification will use the geothermal energy. In this study, as the fundamental investigation to develop the highly efficient LNG vaporizer, When cold energy (Heat Flux : -100, -200, -300 W/m2) is connected to the ground, The soil temperature have been investigated numerically by the unsteady heat conduction equation.
2륜 자동차용 세라믹 촉매변환기내 압력특성과 유동균일도에 관한 수치해석
이중섭,이용훈,정효민,정한식,Yi, Chung-Seub,Lee, Yonghun,Jeong, Hyomin,Chung, Han-Shik 대한기계학회 2007 大韓機械學會論文集B Vol.31 No.4
This research represents the catalytic converter for application in the motorcycle. We have to consider about catalytic converter for reducing exhaust gas strength regarding the displacement volume enlargement. The catalytic converter has been widely used to satisfy the regulations of pollutant emissions from automobiles. Recently, all catalytic converter researches are about automobile. Study about motorcycle catalytic converter has not been conducted yet. In this study, flow uniformity and pressure distribution were simulated in the monolithic inlet of catalytic converter for motorcycle. Exhaust pulsation pressure was set as transient condition about. It was found that flow uniformity shown in base model (0.85) was lower than megaphone model (0.98).
Lubi Rahadiyan,HyoMin Jeong(정효민),HanShik Chung(정한식),김필환 한국동력기계공학회 2006 한국동력기계공학회 학술대회 논문집 Vol.- No.-
This study presents characteristics of Eco-Friendly cascade vapor compression refrigeration system, where two non-ODP and low GWP refrigerants of Propane and Ethane were applied at high and low stage system. These refrigerants were charged into the system which is initially designed for R22 and R23 refrigeration system. By varying the amount of refrigerant charged into the high-stage circuit by 0.1800~0.3470 ㎏, temperature, pressure, and power consumption of the system was observed. The most influenced temperature distribution by the variation of high stage refrigerant mass is temperature of cascade evaporator outlet (HS evaporator outlet) and compressor outlet temperature in the high stage circuit. Evaporation temperature in the low stage system decreases as the mass of refrigerant R290 in the high stage increases. Finally, compressor electric power consumption decreases as the mass of the refrigerant in the high stage increase.
계면활성제를 첨가한 그래핀 나노유체의 분산 특성에 관한 연구
성헌진(HeonJin Seong),정효민(HyoMin Jeong),박준성(JounSung Park),전종훈(JongHoon Jeong),허선철(SunChul Huh) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11
Graphene has excellent electrical conductivity, mechanical properties, and heat transfer properties. It is expected that the heat transfer efficiency will be improved by fabricating the nanofluid. However, graphene is prone to sedimentation because of its cohesion due to van der Waals’ binding forcein this study, we fabricated a nanofluid with enhanced dispersibility by surfactant and ball milling process. The dispersibility, zeta potential, absorbance and thermal conductivity of the nanofluid was measurede.
MATHEMATICAL MODELING OF CO₂ RELEASE IN MULTI-EFFECT DISTILLER
바야라 나산(Bayaraa Nasan),정효민(Hyomin Jeong),정한식(Han-Shik Chung),최두열(Du-Yeal Choi) 대한설비공학회 2011 대한설비공학회 학술발표대회논문집 Vol.2011 No.7
The release of CO₂ in multiple-effect distillers has been barely investigated and less attention has been paid about it. Non-condensable (NC) gases accumulate in condensing zones and reduce the heat transfer for condensation. Even small amounts of NC gases have a significant adverse effect on the condensation heat transfer rate. For predicting the CO₂release rates in MED, the theory of desorption with chemical reaction was applied. The mass transfer processes and the reaction kinetics controlling the CO₂ release were described. In this paper, a mathematical model developed to understand the physical and chemical processes of CO₂ release and carbonate system in multiple-effect distiller.
A study on the characteristic of porous media
Jin Meihua(진미화),Pilhwan Kim(김필환),Hyomin Jeong(정효민),Hanshik Chung(정한식) 한국동력기계공학회 2007 한국동력기계공학회 학술대회 논문집 Vol.- No.-
since porous medium will increase the performance of heat exchanger, porous medium is of growing interest in a wide range of engineering. But as the penalty of increasing heat transfer coefficient ,increasing of pressure drop should be taken into consideration. This paper represent an experiment, which is to used measure α and β of two copper porous medium (20ppi and 40ppi) with different porosity. α and β are important factor of pressure drop. Finally we got the relationship equation between unit pressure drop and velocity.