http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
강주원(Kang, J. W.),홍지우(Hong, J. W.),강관형(Kang, K. H.) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11
Optical beam steering is an essential element for optical communications, laser detection, ranging (LADAR), and solar cell. Electrowetting, which is a phenomenon that changes the contact angle of a liquid on a solid surface using electrical force, can be used to control optical beam. This device is called electrowetting-driven micro prism (EMP). Prism size, viscosity of the ambient fluid, electrical signal, and interfacial tension can affect the performance and stability of EMP. In this study, the effects of these factors on meniscus dynamics in EMP are investigated both experimentally and numerically. Especially, we explore how viscosity and electrical signal affect the switching time (i.e., the time to reach the either peak or equilibrium) and the maximum contact line velocity. Finally, we observe the entrapment of ambient oil and small oil drops formed by film instability in EMP system and investigate the effects of viscosity of the ambient fluid and electrical voltage on the size distribution of oil drops.
레벨셋 기법을 이용한 전기습윤 현상의 동적 거동에 대한 해석
박준권(J.K. Park),홍지우(J.W. Hong),강관형(K.H. Kang) 한국전산유체공학회 2009 한국전산유체공학회 학술대회논문집 Vol.2009 No.11
Electrowetting is a versatile tool to handle tiny droplets and forms a backbone of digital microfluidics. Numerical analysis is necessary to fully understand the dynamics of electro wetting, especially in designing electro wetting-based devices, such as liquid lenses and reflective displays. We developed a numerical method to analyze the general contact-line problems, incorporating dynamic contact angle models. The method is based on the conservative level set method to capture the interface of two fluids without loss of mass. We applied the method to the analysis of spreading process of a sessile droplet for step input voltages and oscillation of the droplet for alternating input voltages in electro wetting. The result was compared with experimental data. It is shown that contact line fiction significantly affects the contact line motion and the oscillation amplitude. The pinning process of contact line was well represented by including the hysteresis effect in the contact angle models.