• The Korean Journal of Rheology
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• v.6 no.2
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• pp.119-128
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• 1994

공압출되는 sheet die에서 뉴튼 유체의 수축흐름을 격자생성법을 이용한 유한차분법 을 사용하여 수치모사하였다. 계면조건의 처리방법을 개발하였고 점도 및 채널 모양이 압력 강하 및 신장속도에 미치는 영향을 알아보았다. 압력강하는 점도비의 영향을 크게 받았으며 신장속도는 점도비 및 채널 모양의 영향을 크게 받았다. 여러 가지채널모양에서 신장속도를 비교해 본 결과, 트럼펫 모양의 수축채널이 신장속도가 가장속도가 가장 작게 나타났다.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1634-1639
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• 2004

The present study concerns a experimental study of fully developed laminar flow of a Newtonian and non-Newtonian fluid through a concentric annulus with a combined bulk axial flow and inner cylinder rotation for the various radius ratio. This study shows the fundamental difference between Newtonian and non-Newtonian fluid flow in an annulus for various radius ratio.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.6
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• pp.23-31
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• 2012

Present work deals three families of $SiO_2$ gelling agents which have been used to produce gel fuel based on Kerosene. Jet A-1 is chosen as fuel where power-law rheological model is used to confirm whether or not the gelification is achieved depending on the %wt of gellant. It was confirmed that the produced jelly-like substance have shear-thinning effect, and that its apparent viscosity increases as $SiO_2$ concentration increases. Compared to other gellants, gel with Aerosil(R) R972 fits most to the power-law model, while gels with Silica 230 and Silica 530 deviate from the power-law model. The rheological characteristics behaved differently depending on the mixing method(vortex mixing and manual mixing) when gellant concentration is increased.