• Journal of computational fluids engineering
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• v.21 no.4
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• pp.90-95
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• 2016

Leidenfrost drops with ellipsoidal shaping can control the bouncing height by adjusting the aspect ratio(AR) of the shape at the moment of impact. In this work, we focus on the effect of the AR and the impact Weber number(We) on the non-axisymmetrical spreading dynamics of the drop, which plays an important role in the control of bouncing. To understand the impact dynamics, the numerical simulation is conducted for the ellipsoidal drop impact upon the perfect non-wetting solid surface by using volume of fluid method, which shows the characteristics of the spreading behavior in each principal axis. As the AR increases, the drop has a high degree of the alignment into one principal axis, which leads to the consequent suppression of bouncing height with shape oscillation. As the We increases, the maximum spreading diameters in the principal axes both increase whereas the contact time on the solid surface rarely depends on the impact velocity at the same AR. The comprehensive understanding of the ellipsoidal drop impact upon non-wetting surface will provide the way to control of drop deposition in applications, such as surface cleaning and spray cooling.

• Journal of Korea Foundry Society
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• v.15 no.4
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• pp.360-367
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• 1995

Effects of metal coating treatment on SiC particle on wetting behavior and interfacial strength were studied. Experimental variables are included types of coated metallic films such as Cu and Ni-P, and temperatures of heat-treatment under vacuum. The experimental results concerning wetting phenomena of liquid Al on SiC, showed that coating treatment of metallic film on SiC particles remarkably improves the wetting behavior of liquid Al on SiC, especially in the case of Ni-P coating. The interfacial strength of Al/SiC composites made of coated SiC plate was higher than that of the composite with non-coated SiC plate although the coating treatment was not perfect.

• Membrane Journal
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• v.7 no.2
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• pp.57-64
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• 1997

Membrane Distillation(MD) is reviewed as an application to new separation technology. Hydrophobic membrane which has been used to microfiltration is feasible material for MD process. MD has perfect selectivity under moderate temperature and is promised to simplify typical water treatment process. The principle of MD separation is phase transition by vapor-liquid interface at the pore of membrane surface. Feed and permeate temperature, composition, membrane wetting, heat and mass transfer phenomena affect the selectivity and flux of MD.

• School Science Journal
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• v.12 no.2
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• pp.218-225
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• 2018

우리나라 화학 교육과정에서 표면장력은 분자 간 상호작용과 함께 지속적으로 제시되어 온 개념이지만, 지금까지 다뤄진 표면장력은 과학적 정의보다는 단순히 현상이나 사례의 측면으로만 제시되는 경향이 있다. 따라서 본 연구에서는 표면장력에 대한 새로운 교수학습 방법을 마련하고자 과학적 정의에 기반을 둔 표면장력 측정 실험 장치를 개발하고자 하였다. 선행 연구에서 제시한 표면장력 측정 장치들의 한계점을 분석하였고, 실험의 직관성, 편리성, 정확성 등에 초점을 맞추어 Wilhelmy 평판법(Wilhelmy plate method) 기반의 표면장력 측정 장치를 개발하였다. 6종 액체의 표면장력을 측정함으로써 제작된 표면장력 측정 장치가 짧은 시간 내에 정확하고 정밀한 값을 측정할 수 있다는 것을 확인하였다. 본 연구에서 제안하는 표면장력 측정 장치는 추후 화학 수업 현장에서 표면장력 교수와 측정을 위해 사용될 수 있다.