http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
미세입자분산 액적의 고체면에서 모세퍼짐 현상에 관한 직접수치해석 기법개발
황욱렬(Wook Ryol Hwang),정현준(Hyun Jun Jeong),김시조(See Jo Kim),김종엽(Chongyoup Kim) 한국전산유체공학회 2007 한국전산유체공학회지 Vol.12 No.4
We present a direct numerical simulation technique and some preliminary results of the capillary spreading of a droplet containing particles on the solid substrate. We used the level-set method with the continuous surface stress for description of droplet spreading with interfacial tension and employed the discontinuous Galerkin method for the stabilization of the interface advection equation. The distributed Lagrangian-multipliers method has been combined for the implicit treatment of rigid particles. We investigated the droplet spreading by the capillary force and discussed effects of the presence of particles on the spreading behavior. It has been observed that a particulate drop spreads less than the pure liquid drop. The amount of spread of a particulate drop has been found smaller than that of the liquid with effectively the same viscosity as the particulate drop.
미세입자분산 액적의 고체면에서 충돌과 퍼짐현상에 관한 직접수치해석 기법개발
정현준(Hyun Jun Jeong),황욱렬(Wook Ryol Hwang),김종엽(Chongyoup Kim) 한국전산유체공학회 2008 한국전산유체공학회지 Vol.13 No.3
We present a numerical simulation technique and some preliminary results of the impact and spreading of a droplet containing particles on the solid substrate in 2D. We used the 2nd-order Adams-Bashforth / Crank-Nicholson method to solve the Navier-Stokes equation and employed the level-set method with the continuous surface stress for description of droplet spreading with interfacial tension. The impact velocity has been generated by the instantaneous gravity. The distributed Lagrangian-multipliers method has been combined for the implicit treatment of rigid particles and the discontinuous Galerkin method has been used for the stabilization of the interface advection equation. We investigated the droplet spreading by the inertial force and discussed effects of the presence of particles on the spreading behavior using an example problem. We observed reduced oscillation and spread for the particulate droplet.
탄소 나노튜브 나노유체의 수평관에서의 압력강하 특성에 관한 연구
고권현(Gwon Hyun Ko),허경윤(Kyungyoon Heo),이경준(Kyungjun Lee),김대성(Dae Seong Kim),김종엽(Chongyoup Kim),손양수(Yangsoo Sohn),최만수(Mansoo Choi) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
This study performs the measurement of thermal conductivity, viscosity, and pressure drop in the pipe flow of the aqueous suspensions of multi-walled carbon nanotubes. Two different methods are used to prepare stable nanotubes suspensions. One of them is to make the surface of nanotubes hydrophilic by acid treatment (TCNT nanofluids), and the other is to disperse nanotubes using sodium dodecyl sulfonate (SDS) as a surfactant (PCNT nanofluids). From the measurement of viscosity, it is observed that nanotubes suspensions are shear thinning fluids, for which the viscosity decreases with increasing shear rate. The enhancement of thermal conductivity is proportional to CNT concentration for both CNT nanofluids. Under laminar flow conditions, the friction factor of PCNT nanofluids is much larger than that of TCNT nanofluids. In contrast to this, under turbulent flow conditions, the friction factors of both nanofluids are similar to that of the base fluids.