• Journal of Power System Engineering
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• v.10 no.1
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• pp.25-33
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• 2006

거칠기가 한 벽면과 두 벽면에 설치된 사각채널에서 비압축성 유체유동과 열전달을 조사하기위해 3차원 수치모사를 행하였다. CFX (version 5) software package 를 사용하여 계산하였다. 거친 벽은 $45^{\circ}$경사진 거칠기가 설치되어 있다. 채널의 4 벽면은 일정한 열 유속으로 가열하였다. 수치계산 결과는 실험값과 잘 일치 하였다. 연구의 조건은 거칠기 피치와 높이의 비가 8이고, 거칠기 높이와 채널 수력직경의 비가 0.067이며, 레이놀즈수의 범위는 7,600에서 24,900이었다. 연구의 결과는 열전달계수와 마찰계수는 사각채널에서 거친 벽면의 수가 클수록 증가 함을 보였다.

• Journal of Power System Engineering
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• v.12 no.4
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• pp.39-45
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• 2008

본 연구는 두 개의 경사진 다공 배플이 설치된 사각채널에서 국부 열전달향상 특성을 조사하였다. 채널은 19.8cm(W)$\times$4cm(H)의 단면적을 가지며 형상계수는 4.95이며 수력직경은 6.66cm이다. 4종류의 배플을 취급하였다. 가열 시험부에 동일한 크기, 경사각, 구멍형태의 경사 배플을 설치하였다. 경사 배플은 모두 19.8 cm의 폭, $2.55cm\times2.55cm$의 정 다이아몬드 형 구멍, 그리고 So의 경사각을 갖는다. 레이놀즈 수 범위는 23,000에서 57,000까지이다. 배플의 구멍의 수가 열전달 향상에 중요한 역할을 하였으며 구멍이 3개 인(baffle type II)가 가장 우수한 열전달 향상을 보였다.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.491-499
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• 2003

The Okinawa Trough is a rift basin formed by extension. Analysis of multichannel seismic reflection profiles from the northwestern margin of the northern Okinawa Trough reveal that the trough is characterized by a series of tilted fault blocks bounded by listric normal faults and half-grabens developed between blocks, showing typical rifted structures. The trough display three kinds of sedimentary sequences with different seismic reflection characteristics: prerift, synrift and postrift sediments. The prerift sequence develops parallel to the dip direction of tilted fault blocks. The synrift sediments, mostly deposited in the half-grabens between tilted fault blocks, are generally well characterized by divergence of the reflectors towards the blocks indicating contemporaneous deposition during tilting. The postrift sediments are featured by continuous and parallel reflectors. The width of the half-graben and the throw-displacement rate of the basin bounding fault are closely connected. The throw-displacement rate is the maximum when the rifting event is the most active and the width of the half-graben is proportional to the rate.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.24.1-24.1
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• 2005

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.433-439
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• 2001

An experimental study was carried out on the characteristics of the mixed-convection heat transfer from a protruding heat source module which had uniform heat flux and was located on a flat plate in the inclined channel. The effects of the inclined channel(${\varphi}=0{\sim}90^{\circ}$) was studied for the input power($Q=3,\;7W$) and inlet air velocities($V_{i}=0.1{\sim}0.9m/s$). Experimental results indicate that the input power was most effective parameter on the temperature differences between inlet air and module. The effects of the inclined angle was negligible when the inlet velocities were above 0.5m/s and 0.9m/s at Q = 3W, 7W respectively. As the inclined angle of the channel increases, the temperatures of the module are decreased. So we obtained the best condition on the adiabatic board at the vertical channel.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.543-554
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• 2004

Analysis of multi-channel seismic reflection and well data serves to detail the structural evolution of the northern Okinawa Trough, southern offshore Korea. The overall structural style of the area is characterized by a series of half grabens and tilted fault blocks bounded by basement-involved listric normal faults. Most half grabens and tilted fault blocks developed in the direction of NNE-SSW, parallel to the axis of the Okinawa Trough. Orientation and distribution of the listric faults also suggest the development of transfer faults in NW-SE direction. The rifting phase of the northern Okinawa Trough have been established on the basis of structural and stratigraphic analyses of depositional sequences and their seismic expressions. Major phase of rifting probably started in the Late Miocene and the most active rifting occurred during the Early Pliocene. The rifting produced a series of half grabens and tilted fault blocks bounded by listric normal faults. It appears that the rifting activity has become weaker since the Late Pliocene, but the Pleistocene sediments faulted by listric faults bounding tilted fault blocks suggest that the rifting activity is probably still in progress.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.471-476
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• 2001

The characteristics of conjugated heat transfer in the inclined channel was experimentally investigated. The simulated module is attached to the bottom of the inclined channel and is heated with constant heat flux. The experimental parameters of this study are input power (Q = 3, 7W), inlet air velocity ($V_{i}=0.1{\sim}0.9m/s$) and inclined channel angle (${\varphi}=0{\sim}90^{\circ}$). The results show that input power was most effective parameter on the temperature differences between module and air. As the inclined channel angle increases, the temperatures of the module are increased. And we obtained the best condition on the conductive board when ${\varphi}=0^{\circ}$.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.1
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• pp.78-85
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• 2005

A numerical calculation is performed to study the effects of buoyancy force on the heat transfer characteristics of laminar forced convection flow in inclined parallel plates with the upper part cooled and the lower Part heated uniformly. Numerical results are presented for the Reynolds number ranges from $4.0\times10^{-3}$ to $1.13\times10^{-1}$. the angle of inclination, $\theta$. from 0 to 90 degree and Pr of the high viscosity fluid is 909. It is found that the flow pattern of mixed convection in inclined parallel Plates can be classified into four patterns which affected by Reynolds number and the angle of inclination.