Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Society of Marine Engineering
Journal Basic Information
Journal DOI :
Korean Society of Marine Engineers
Editor in Chief :
Volume & Issues
Volume 20, Issue 5 - Dec 1996
Volume 20, Issue 4 - Aug 1996
Volume 20, Issue 3 - Jun 1996
Volume 20, Issue 2 - Apr 1996
Volume 20, Issue 1 - Feb 1996
Selecting the target year
Phenomena Occurring in Turbo-Pumps
Kim, Chun-Sik ; Choi, Min-Seon ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 1~11
Phenomena Occurring in Aero-Turbo Machinery
Kim, Man-Eung ; Kim, Jin-Ku ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 12~22
Flow Characteristics of Two-Dimensional Closed Cavity near Unsteady Critical Reynolds Numbers
Kim, Jin-Gu ; Kim, Chun-Sik ; Lee, Yeong-Ho ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 22~29
Flow characteristics of two-dimensional closed square cavities near unsteady critical Reynolds numbers were studied numerically at four Reynolds numbers :
A convection conservative difference scheme based upon SOLA to maintain the nearly 2nd-order spatial accuracy is adopted on irregular grid formation. Irregular grid number is
and its minimum size is about 1/400 of the cavity height(H) and its maximum is about 1/53 H. The result shows that the critical Reynolds number indicating the emergence of flow wnsteadiness is ranging from Re=
and their flow patterns reveal periodic fluctuation during transient and fully developed stages. But macroscopic flow behavior in terms of instantaneous and time-mean characteristics represent remarkable difference.
Development of PIV System by Image Board
Cho, Dae-Hwan ; Choi, Jang-Un ; Doh, Deok-Hui ; Lee, Yeong-Ho ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 30~38
A PIV system consisting of an image board slit into personal computer and 2-D sheet light projector is developed and related techniques to improve its performance are discussed. A grey-level cross correlation method capable of overcoming particle seeding limitation is suggested. And a sub-pixed interpolation method in determining the vector terminal is preposed by considering 8-neighbours correlation distributing patterns. Furthermore, pressure estimation from the acquired velocity vectors by applying the Poisson equation is persented with reasonable feasibility. As a practical application of the present system, evaporator flows are analysed and attained instantaneous velocity vectors reveal that the flow phenomena maintain turbulent fluctuation.
Evaluation of the Anisotropic k -
Turbulence Model by the Numerical Analysis of Axisymmetric Swirling Turbulent Flow
Lee, Yeon-Won ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 39~44
To overcome weak poinks of the standard k-
turbulence model when applied to complex turbulent flows, various modified models were proposed. But their effects are confined to special flow fields. They have still some problems. Recently, an anisotropic k-
turbulence model was also proposed to solve the drawback of the standard k-
turbulence model. This study is concentrated on the evaluation of the anisotropic k-
turbulence model by the analysis of axisymmetric swirling turbulent flow. Results show that the anisotropic k-
turbulence model has scarecely the fundamentally physical mechanism of predicting the swirling structure of flow.
A Numerical Analysis of Turbulent Flow Field and Contamination Behavior in a Three Dimensional Room with Obstacle
Jeong, Hyo-Min ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 45~57
Flow characteristics and contamination behavior in a three-dimensional room with the desk-type obstacle have been investigated numerically by the k-
two equation turbulence model. The room model has one supply opening on the ceiling and two exhaust openings on the side walls. Thirty six sets of calculation have been performed for twelve contamination sources of
strength at different inlet velocities(0.1, 1, 10m/s). This study can conclude that the source points of contaminant are located near the obstacle edge of Z-axis, at which the maximum contaminant diffusion fields are occured.
A Study on Pressure Distribution, Wall Shear Stress and Friction Factor of Developing Turbulent Pulsating Flows in a Square Duct(Ⅰ), -Experimental Analysis-
Park, Gil-Mun ; Cho, Byeong-Gi ; Koh, Yeong-Ha ; Bong, Tae-Geun ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 58~67
In the present study, the pressure distribution, wall shear stress distribution and friction factor of developing turbulent pulsating flows are investigated theoretically and experimentally in the entrance region of a square duct. The pressure distribution for turbulent pulsating flows are in good agreement with the theoretical values. The time-averaged pressure gradients of the turbulent pulsating flows show the same tendency as those of turbulent steady flows as the time-averged Reynolds number
increase. Mean shear stresses in the turbulent pulsating flow increase more in the inlet flow region than in the fully developed flow region and approach to almost constant value in the fully developed flow region. In the turbulent pulsating flow, the friction factor of the quasi-steady state flow
follow friction factor's law in turbulent steady flow. The entrance length of the turbulent pulsating flow is not influenced by the time-averaged Reynolds number
and it is about 40 times as large as the hydraulic diameter.
An Experimental Study on Vacuum Drying of Water-Saturated Porous Media
Park, Hyeong-Jin ; Kim, Gyeong-Geun ; Kim, Myeong-Hwan ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 68~75
The vacuum drying characteristics of water-saturated porous media were studied experimentally. The water-saturated porous media, water-saturated sand layer, was heated by the isothermal bottom wall of the rectangular vessel. The vacuum drying rate and temperature distribution of the sand layer were measured and calculated under a variety of conditions of heated wall temperature, vacuum rate, and thickness of the test material. It was found that the drying rate due to the heat and mass teansfer is greatly influenced by the heated wall temperature, vacuum rate, and thickness of the test material.
A Study on the fin efficiency of continuous fin - tube heat exchanger, -In the case of sensible heat transfer-
Jung, Hyeong-Ho ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 76~81
In this paper, a calculation method for fin efficiency of continuous fin is introduced. The continuous fin of in-line and staggered arrangement was divided into many sectors and fin efficiencies of each sectors were calculated by assuming that each sectors be the circular fins. To get the converged fin efficiency which is averaged by the each areas, the number of sectors was increased. The results were compared with equivalnet method by varying the aspect ratios in both cases of in-line and staggered tube arrangement and showed some differences of fin efficiencies.
Computer Simulation of the Electronic Hydraulic Ultra - High Pressure Fuel Injection System
Jang, Se-Ho ; Ahn, Su-Gil ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 82~92
A computer simulation with predict the fuel injection rates and the fuel injection pressure behaviors in diesel engine fuel injection systems would by very useful in designing or improving fuel injection systems. In this paper we developed computer program in order to predict the behaviors of the fuel injection rate and the injection pressure for Electronic Hydraulic Ultra-High Pressure Fuel Injection System. We've applied the continuity and momentum equations for the hydraulic phenomena and the dynamics of individual components of the Electronic Hydraulic Fuel Injection System. To solve all the equations numerically we've applied the Runge-kutta IV method. Water hammer equations were applied for the hydraulic pipe solution, and the method of characteristics was employed in our calculations. The simulation results were compared with the experimental results for: Accumulator pressure, Injection pressure and unjection rate. As a result, The simulation results agree very well with our experimental results. We found that a large accumulator and the high speed solenoid valve were required, and the compression volume of the fuel had to be as small as possible in order to acheive ultra-high pressure fuel injection.
Interaction of Laser Beam with PZT - Target and Observation of Laser - Induced Plume and Particle Ejection
Lee, Byeong-U ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 93~102
Laser-induced plume and laser-target interaction during pulsed laser deposition are demonstrated for a lead zirconate titanate (PZT). A KrF excimer laser (wavelength 248nm) was used and the laser was pulsed at 20Hz, with nominal pulse width of 20ns. The laser fluence was~
with 100mJ per pulse. The laser-induced plasma plume for nanosecond laser irradiation on PZT target has been investigated by optical emission spectra using an optical multichannel analyzer(OMA) and by direct observation of the plume using an ICCD high speed photography. OMA analysis showed two distinct ionic species with different expansion velocities of fast or slow according to their ionization states. The ion velocity of the front surface of the developing plume was about
cm/sec and corresponding kinetic energy was about 100eV. ICCD photograph showed another kind of even slower moving particles ejected from the target. These particles considered expelled molten parts of the target. SEM morphologies of the laser irradiated targets showed drastic melting and material removal by the laser pulse, and also showed the evidence of the molten particle ejection. The physics of the plasma(plume) formation and particle ejection has been discussed.
Preparation of New Corrosive Resistive Magnesium Coating Films
Lee, Myeong-Hun ;
Journal of the Korean Society of Marine Engineering, volume 20, issue 5, 1996, Pages 103~113
The properties of the deposited film depend on the deposition condition and these, in turn depend critically on the morphology and crystal orientation of the films. Therefore, it is important to clarify the nucleation occurrence and growth stage of the morphology and orientation of the film affected by deposition parameters, e.g. the gas pressure and bias voltage etc. In this work, magnesium thin flims were prepared on cold-rolled steel substrates by a thermo-eletron activation ion plating technique. The influence of nitrogen gas pressure and substrate bias voltage on their crystal orientation and morphology of the coated films were investigated by scanning electron microscopy (SEM) and X-ray diffraction, respectively. The diffraction peaks of magnesium film became less sharp and broadened with the increase of nitrogen gas pressure. With an increase in nitrogen gas pressure, flim morphology changed from colum nar to granular structure, and surface crystal grain-size decreased. The morphology of films depended not only on gas pressure but also on bias voltage, i.e., the effect of increasing bias voltage was similar to that of decreasing gas pressure. The effect of crystal orientation and morphology of magnesium films on corrosion behaviors was estimated by measuring anodic polarization curves in deaerated 3%NaCl solution. Magnesium, in general, has not a good corrosion resistance in all environments. However, these magnesium films prepared by changing nitrogen gas pressure showed good corrosion resistance. Among the films, magnesium films which exhibited granular structure had the highest corrosion resistance. The above phenomena can be explained by applying the effects of adsorption, occlusion and ion sputter of nitrogen gas.