• 동력기계공학회지
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• 제10권2호
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• pp.29-35
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• 2006

Two-dimensional numerical simulation has been performed to investigate mixed convection heat transfer between inclined parallel plates with bottom-heated and top-cooled uniformly. The ratio of parallel plate length to height is 9.33, Prandtl number is 909(that of silicone oil at 298K) and Rayleigh number is 8600. In the ranges of the Reynolds number Re from 0 to 1.8 and the angle of inclination ${\theta}$ from 0 to 90 degree. The governing equations are discretized using the finite volume method. In this study, the effects of the Reynolds number, the angle of inclination, and the local and mean Nusselt numbers are presented and discussed. It is found that the periodic flow of mixed convection between inclined parallel plates is shown at $0^{\circ}{\leq}\;{\theta}<30^{\circ},\;Re<0.063$, and the flow pattern can be classified into three patterns which depend on Reynolds number and the angle of inclination. The minimum average Nusselt numbers occur at Re=0.05 regardless of the angle of inclination.

• 한국해양공학회지
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• 제35권2호
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• pp.113-120
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• 2021

In order to perform a precise wave tank experiment, it is necessary to maintain the incident wave generated by the wavemaker in a steady state and to effectively remove the reflected waves. In this paper, a combined sloping-wall-type punching plate wave absorber was proposed to attenuate reflected waves effectively in a two-dimensional mini wave tank. Using the four-point reflection separation method, the reflected waves were measured to determine the reflection coefficients. Experiments were conducted under various punching plate porosities, sloping plate angles, and incident wave conditions to evaluate the performance of the combined punching plate wave absorber. The most effective wave absorbing performance was achieved when the porosity was 10% and the inclination angle of the punching plate was 18.6° under the present condition. It was also found that the installation of the sloping plate could improve the wave attenuation performance by generating the shoaling effect of the incident wave.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2000년도 춘계학술대회 논문집(Proceeding of the KOSME 2000 Spring Annual Meeting)
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• pp.153-158
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• 2000

Flow visualization and PIV measurements were conducted to investigate the flow characteristics of multi-channel with inclination angle. The water flow seeded with tiny vegetable powder as tracers revealed details of flow field. The PIV measurement to acquire multi-point velocity data simulatneously was carried out at three space of plates for 5, 10, and 15mm with variation of inlet flow rates of $0.25m^3/h$ and <$0.5m^3/h.$ Experiment results show that space of plates acts a significant role in separating process.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1394-1399
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• 2004

Recently solar energy is representative in the technology development and spread of alternative energy. Specially in condition of solar collectors, they have had very various shape. This paper reports experimental study about the application of Oscillating Capillary Tube Heat Pipe to flat-plate solar collector. In conclusion, overall temperature distribution of OCHP was investigated by charging ratio and inclination angle. Respective charging ratio is 15%, 20%, 40% and respective inclination angle is horizontal, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, perpendicular. As a result of experiment, charging ratio 20% heat pipe has shown the most uniform temperature distribution and also performance of heat transfer has been the best.

• 동력기계공학회지
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• 제13권2호
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• pp.11-17
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• 2009

The heat transfer characteristics of flow through two inclined wire-mesh baffles in a rectangular channel were investigated experimentally with varying the mesh number of wire screens and inclination angle of the baffles. Two different types of wire meshes such as dutch and plain weaves, were used in this experiment. Three kinds of baffle plates with different mesh specifications in the dutch weave and four different kinds in the plain weave were manufactured. Baffles were mounted on bottom wall with varied angles of inclination. Reynolds number was varied from 23,000 to 57,000. It is found that the placement of inclined wire-mesh baffles in the channel affects the heat transfer characteristics by combining both jet impingement and flow disturbance. The wire screen modified the flow structure leading to a change in the heat transfer characteristics. The results show that the baffle plate with the most number of mesh (type SA) has the highest heat transfer rate.

• 산업경영시스템학회지
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• 제31권4호
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• pp.146-152
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• 2008

This study was aimed to understand the effects of perturbed floor surface on human postural stability while standing. Ten subjects were asked to stand quietly on the surface with two angles of inclination ($0^{\circ}$ and $5^{\circ}$), two contamination conditions (dry and oil-contaminated), and three commercial floor materials (ceramic tile, coated wood, and vinyl tile). During each trial, a force plate with data acquisition systems was used to collect subject's center of pressure (COP) position. Measured COPs were then converted into the length of postural sway path in both subject's anterior-posterior (AP) and medio-lateral (ML) axis. Results showed that the length of sway path in ML axis was significantly affected by the angle of inclination and the type of floor material. The sway length was increased significantly at the inclination angle of $5^{\circ}$ and on the vinyl tile, respectively. The contamination condition, however, did not significantly affect the postural sway length in both AP and ML axis. The results imply that a proper treatment of floor surface and material is critical to preserving postural balance while standing.

• Steel and Composite Structures
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• 제37권3호
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• pp.341-351
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• 2020

Steel plate shear wall with self-centering energy dissipation braces (SPSW-SCEDB) is a lateral force-resisting system that exhibits flag-shaped hysteretic responses, which consists of two pre-pressed spring self-centering energy dissipation (PS-SCED) braces and a wall plate connected to horizontal boundary elements only. The present study conducted a series of cyclic tests to study the hysteretic performances of braces in SPSW-SCEDB and the effects of braces on the overall hysteretic characteristics of this system. The SPSW-SCEDB with PS-SCED braces only exhibits excellent self-centering capability and the energy loss caused by the large inclination angle of PS-SCED braces can be compensated by appropriately increasing the friction force. Under the combined effect of the two components, the SPSW-SCEDB exhibits a flag-shaped hysteretic response with large lateral resistance, good energy dissipation and self-centering capabilities. In addition, the wall plate is the primary energy dissipation component and the PS-SCED braces provide supplementary energy dissipation for system. The PS-SCED braces can provide up to 90% self-centering capability for the SPSW-SCEDB system. The compressive bearing capacity of the wall plate should be smaller than the horizontal remaining restoring force of the braces to achieve better self-centering effect of the system.

• 한국군사과학기술학회지
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• 제10권1호
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• pp.33-43
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• 2007

Using the more common conventional chordwise aerodynamic approach, flapping a flat plate wing with zero degree chordwise pitch angle of attack and no relative wind should not produce lift. However, in hover, with no forward relative velocity and zero degree chordwise pitch angle of attack, flapping flat plate wings does in fact produce lift. In the experiments peformed for this paper, the flapping motion is considered pure(downstroke and upstroke) with no flapping stroke plane inclination angle. No changes in chordwise pitch angle are made. The total force is measured using a force transducer and the net aerodynamic force is determined from this measured total force by subtracting the experimentally determined inertial contribution. These experiments were repeated at various flapping frequencies and for various wing planform sizes for flat plate wings. The trends in the aerodynamic lift variation found using a force transducer have nearly identical shape for various flapping frequencies and wing planform sizes.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.80-83
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• 2004

The FRP plate or sheet bonding technology was widely used for strengthening deficient RC structures. The strengthened structure using FRP bonding scheme, however, experience the complex interfacial behaviour which is difficult to predict. Therefore, the unbonded scheme using some anchorage device can be is an alternative for more reliable design. In this study, wedge-type anchor for FRP plate is developed for the unbonded flexural strengthening scheme. Some parameter study using 2D finite element method is performed. The analysis parameters are taken as wedge-guide friction coefficients, wedge- FRP ,.friction coefficient and wedge inclination angle. Based on the parameter study, more efficient anchors are designed and tested. The test result show that the developed anchor assure about $80\%$ FRP strength, which is higher performance than typical bonding scheme. Last, 3D finite element analysis is performed.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제20권4호
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• pp.355-374
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• 2016

This work is devoted to investigate heat and mass transfer effects on MHD natural convection flow past an inclined plate with ramped temperature numerically. The dimensionless governing equations for this investigation are solved by using finite element method. The effects of angle inclination, buoyancy ratio parameter, permeability parameter, magnetic parameter, Prandtl number, heat generation, thermal radiation, Eckert number, Schmidt number, chemical reaction parameter and time on velocity, temperature and concentration fields are studied and presented with the aid of figures. The effects of the pertinent parameters on skin friction, rate of heat transfer and mass transfer coefficients are presented in tabular form. The numerical results are compared graphically with previously published result as special case of the present investigation and results found to be in good agreement.