• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.6
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• pp.1321-1329
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• 1989

본 논문에서는 성층화된 용액ㅇ네 수평방향으로 온도구배가 가해지는 경우에 있어서 두 부력인자의 상대적 크기에 따라 나타나는 유동형태와 그에 따른 온도, 농도 분포 및 열전달특성을 수치적으로 연구하고자 한다.

• Journal of Ocean Engineering and Technology
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• v.6 no.2
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• pp.143-150
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• 1992

Numerical simulation is made of a stably stratified salt-water solution due to lateral heating in an equilateral trapezoidal enclosure using boundary-fitted coordinate in grid generation. Results show four types of the global fluid pattern depending on the buoyancy ratio in the enclosure, i.e., unicell flow pattern for the low buoyancy ratio, layered flow pattern for the increasing buoyancy ratio, layered flow pattern with stagnant zone for the relatively high buoyancy ratio and stagnant flow pattern for the much higher buoyancy ratio.

• Journal of Ocean Engineering and Technology
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• v.8 no.1
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• pp.105-113
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• 1994

Double-diffusive convection induced by simultaneously-imposed lateral temperature and concentration gradients in a rectangular enclosure with aspect retio, 2.0 has been studied experimentally for adiabatic and isothermal horizontal boundary conditions. Visual observations show two distinct flow structures depending on the buoyancy ratio. The unicell flow structure is observed for a lower buoyancy ratio while the layered flow structure appears for a higher buoyancy ratio. There exists an unstable flow regime between two buoyancy ratios.

• Journal of the Korean earth science society
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• v.42 no.2
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• pp.185-194
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• 2021

A lava dome and sheet lava flow can be observed at the seashore of Aewol, Jeju island. The cylindrical lobes are characterized by a concentric structure consisting of a massive core and radial joints. Columnar joints with different thickness between the upper and lower parts are developed in the sheet lava flow around the rock salt field in Goeomri. The upper part of the columnar joints is uneven in shape, and has a diameter of 120-150 cm. The lower part of the columnar joints is hexagonal and pentagonal in shape, and has a diameter of about 60 cm. The cylindrical lobes can be divided into two groups based on size and shape. One is a megalobe, with a semicircular outline and a maximum diameter of 30 m. The other is a circular lobe with a diameter of less than 10 m. The columns in the radial joints have hexagonal and pentagonal cross sections and gradually increasing diameter, outward from the core, to a size of 80-120 cm at the rim. The concentric structure observed in the cylindrical lavas is attributable to a combination of four factors. The first is a circular crack caused by the decrease of the temperature and density difference between the inside and outside of the cylindrical lava flow. The second is a concentric chisel mark of the radial joints, which formed at the same time as the radial joints. The third is a flow band, which is a trace left in a round passage when lava flows through. The fourth is a vesicular band formed in a cave by gas bubbles escaping from the lava flow.