• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.299-306
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• 1989

The combined convective heat transfer from vertical parallel plates with constant temperature has been studied by numerical method. The governing equations for the system are solved by the finite difference method and successive over relaxation scheme for Re$_{L}$ = 50 - 500, Gr = 10$^{4}$, Pr = 0.7. Results for various plate spacings and plate lengths are as follows ; For various plate spacings, the mean Nusselt number increases and then decreases as the dimensionless plate spacing increases. The optimum plate spacing for maximum mean Nusselt number decreases with increasing Reynolds number and can be expressed as a function of Reynolds number. For various plate lengths, the mean plate Nudest number increases as the dimensionless plate length decreases and Reynolds number increases.

• Structural Engineering and Mechanics
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• v.29 no.1
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• pp.91-111
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• 2008

This paper outlines the development of a computational model in order to analyze the dynamic behaviour of coupled fluid-structure systems such as a) liquid containers, b) a set of parallel or radial plates. In this work a hybrid fluid-solid element is developed, capable of simulating both membrane and bending effects of the plate. The structural mass and stiffness matrices are determined using exact integration of governing equations which are derived using a combination of classical plate theory and a finite element approach. The Bernoulli equation and velocity potential function are used to describe the liquid pressure applied on the solid-fluid element. An impermeability condition assures a permanent contact at the fluid-structure interface. Applications of this model are presented for both parallel and radial plates as well as fluid-filled rectangular reservoir. The effect of physical parameters on the dynamic behaviour of a coupled fluid-structure system is investigated. The results obtained using the presented approach for dynamic characteristics such as natural frequency are in agreement to those calculated using other theories and experiments.

• Structural Engineering and Mechanics
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• v.86 no.1
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• pp.69-83
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• 2023

Analytical solutions to problems are crucial because they provide high-quality comparison data for assessing the accuracy of numerical solutions. Benchmark analytical solutions for the vibrations of cracked functionally graded material (FGM) plates are not available in the literature because of the high level of complexity of such solutions. On the basis of first-order shear deformation plate theory (FSDT), this study proposes analytical series solutions for the vibrations of FGM rectangular plates with side or internal cracks parallel to an edge of the plates by using Fourier cosine series and the domain decomposition technique. The distributions of FGM properties along the thickness direction are assumed to follow a simple power law. The proposed analytical series solutions are validated by performing comprehensive convergence studies on the vibration frequencies of cracked square plates with various crack lengths and under various boundary condition combinations and by performing comparisons with published results based on various plate theories and the theory of three-dimensional elasticity. The results reveal that the proposed solutions are in excellent agreement with literature results obtained using the Ritz method on the basis of FSDT. The paper also presents tabulations of the first six nondimensional frequencies of cracked rectangular Al/Al2O3 FGM plates with various aspect ratios, thickness-to-width ratios, crack lengths, and FGM power law indices under six boundary condition combinations, the tabulated frequencies can serve as benchmark data for assessing the accuracy of numerical approaches based on FSDT.

• Journal of Mechanical Science and Technology
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• v.20 no.1
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• pp.125-132
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• 2006

To understand fluid dynamic forces acting on a structure subjected to two-phase flow, it is essential to get detailed information about the characteristics of two-phase flow. Stratified steady and unsteady two-phase flows between two parallel plates have been studied to investigate the general characteristics of the flow related to flow-induced vibration. Based on the spectral collocation method, a numerical approach has been developed for the unsteady two-phase flow. The method is validated by comparing numerical result to analytical one given for a simple harmonic two-phase flow. The flow parameters for the steady two-phase flow, such as void fraction and two-phase frictional multiplier, are evaluated. The dynamic characteristics of the unsteady two-phase flow, including the void fraction effect on the complex unsteady pressure, are illustrated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.5 no.3
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• pp.244-250
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• 1981

The rediant heat tranfer and temperature distribution between infinite parallel gray plates at different temperatures separated by an absorbing and emitting gray gas with or without a sinusoidal heat source in the gas are analyzed by Monte Carlo method. The Monte Carlo result were compared with the numerical solution by Usiskin and Sparrow and the exact solution by Hottel in the case of similar problem limited black walls and gas optical thickness is less than two. For gray walls and large optical thichness the results were compared with modified diffusion approximate solution by Deissler.

• Clinics in Shoulder and Elbow
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• v.18 no.2
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• pp.105-112
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• 2015

In orthopedic trauma surgery, treatment of intraarticular distal humerus fractures is a challenge. With development of implants and biomechanical studies, surgical strategies with recommendations including preoperative computed tomography images, proper approaches and open reduction and internal fixation with dual plates have emerged. In addition, as an effort to provide stable fixation to permit early elbow motion, different methods of internal fixation, particularly plate configuration, have evolved. Using dual plates, either oriented parallel to each other or orthogonal, stable fixation has been achieved and satisfactory clinical outcomes have been reported. With rationales and advantages/disadvantages of each plate configuration, both techniques are selected according to surgeons' preference, and, in specific cases, one could be preferred over another. The key to successful fixation by either technique is obtaining anatomical reduction with restoration of two stable columns of the distal humerus.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1585-1586
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• 2006

This paper conducts a study on the way the PCB's parallel plates' performances are affected by the loading of low cap. elements such as low cap-decoupling capacitors in conjunction with other lumped element. The fields and impedance profiles are rigorously evaluated and analyzed on various cases loaded with the above components and their effects will be given to bring better PCB EMC schemes.

• Journal of Sensor Science and Technology
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• v.8 no.4
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• pp.347-353
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• 1999

We constructed an interferometer for precise measurement of the ball diameter, and measured the diameter of steel ball with a diameter of 78 mm. The interferometer was consisted of etalon to instal ball between two parallel plates and placed on the monolithic flexure to be moved parallel. The ball diameter was calculated from phase difference of one pair of signals interfered between the both sides of ball and two parallel plates, and the signals was observed by photodetectors with scanning the etalon. The results showed that the diameter of steel ball was 78.1893544 mm and measurement uncertainty of 29 nm in confidence level of 95.5%.

• Journal of Ocean Engineering and Technology
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• v.19 no.4 s.65
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• pp.9-14
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• 2005

In the present paper, the wave absorbing performance of the fully submerged horizontal porous plates has been investigated, numerically and experimentally. The submerged porous system is composed of multi-layered horizontal porous plates that are clamped at the vertical setwall, which are slightly inclined and placed vertically, in parallel, with spacing. The hydrodynamic interaction of incident waves with the rigid porous multi-layered plates was formulated within the context of linear wave-body interaction theory and Darcy's law. In order to validate the effectiveness of the present computing code, the numerical results were compared with the analytical and experimental results. It is found that triple horizontal porous plates with slight inclination, if properly tuned for wave energy dissipation against the standing waves in front of the vertical wall, can have high performances in reducing the reflected wave amplitudes against the incident waves over a wide range of wave frequency.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.9
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• pp.546-551
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• 2000

A micromechanical switch that can be used as a logic gate is described in this paper. This switch consists of fixed input electrodes an output electrode Vcc/GND electrodes and movable plates suspended by crab-leg flexures. for mechanical switching of an electrical signal a parallel plate actuator which comes in contact with output electrode was used. Provided that movable plates are connected to Vcc and a low input voltage(ground signal) is applied to the fixed input electrodes the movable plates are pulled by an electrostatic force between the fixed input electrodes and the movable plates. the proposed micromechanical switch was fabricated by surface micromachining technology with$2\mum$ -thick poly-Si and the measured threshold voltage for ON/OFF switching was 23.5V.