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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Society of Marine Engineering
Journal Basic Information
Journal DOI :
Korean Society of Marine Engineers
Editor in Chief :
Volume & Issues
Volume 26, Issue 6 - Nov 2002
Volume 26, Issue 5 - Sep 2002
Volume 26, Issue 4 - Jul 2002
Volume 26, Issue 3 - May 2002
Volume 26, Issue 2 - Mar 2002
Volume 26, Issue 1 - Jan 2002
Selecting the target year
The present situation and technical trends of the fluid machinery industry
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 622~630
Vibration Control of Engine Body for Two Stroke Low Speed Diesel Engine using Dynamic Vibration Absorber
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 631~637
Two stroke low speed diesel engines are used as a power supplier not only for marine vessel but also diesel power plant with a benefit of its higher mobility and durability than the other thermal engines. However, there are some disadvantages such as the bigger vibrating excitation forces generated by high combustion pressure in cylinders which various kinds of vibrations are caused. In this paper, it is theoretically studied to control engine body vibration using dynamic vibration absorber. As an actual case, dynamic absorbers are designed for controlling X-mode vibration of 9K80MC-S engine on the diesel power plant and its performance is identified by the vibration test both in shop and site
Speed Control of Marine Diesel Engines Using Fuzzy Gain Scheduling
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 638~645
This paper presents a scheme for integrating PID control, gain scheduling and emerging techniques in the field of artificial intelligence, such as fuzzy logic and genetic algorithms for the speed control of a marine diesel engine. At first, local PID controllers are designed based on a local model obtained at each speed mode, whose parameters are optimally tuned using a real-coded genetic algorithm. Then, fuzzy "if-then" rules combine the local controllers as a consequence part to implement fuzzy gain scheduling. To demonstrate the performance of the proposed fuzzy PID controller on overall operating conditions, a set of simulation works on B'||'&'||'W's 4L80MC diesel engine are carried out.t.
The Effect of Reciprocating Motion on Heat Transfer in the Roughened Rectangular Channel
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 646~652
The influence of reciprocating frequency and radius on heat transfer in the roughened rectangular channel is experimentally investigated. The aspect ratio (width/height) of the duct is 2.33 and the rib height is one fifteenth of the duct height. And the ratio of rib-to-rib distance to rib height is 10. The discrete ribs were periodically attached to the button wall of the duct with a parallel orientation. The parametric test matrix involves Reynolds number, reciprocating, and reciprocating radius, in the ranges, 1,000∼6,000, 1.7∼2.5 HB and 7∼15cm, respectively. The combined effects of reciprocating frequency and reciprocating radius have considerable influence on the heat transfer due to the modified vortex flow structure.
The Influence of Shield Gas Ratio on the Toughness of Al5083-O GMA Welding Zone
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 653~660
In this study, the toughness was evaluated by using the instrumented Charpy impact testing procedures for A15083-O aluminum alloy used in the LNG carrying and storing tank. The specimens were GMAW welded with four different mixing shield gas ratios (Ar100%+He0%, Ar67%+He33%, Ar50%+He50%, and Ar33%+He67%), and tested at four different temperatures(+25, -30, -85, and
) in order to investigate the influence of the mixing shield gas ratio and the low temperature. The specimens were divided into base metal, weld metal, fusion line, and HAZ specimen according to the worked notch position. From experiment, the maximum load increased a little up to -
, and the maximum load and maximum displacement were shown the highest and the lowest at -
than the other test temperatures. The absorption energy of weld metal notched specimens was not nearly depends on test temperature and mixing shield gas ratio because the casting structure was formed in weld metal zone. In the other hand, the other specimens were shown that the lower temperature, the higher absorption energy slightly up to
but the energy was decreased so mush at
Experiments on Selective Laser Sintering of WC-Co Mixture for Rapid Metal Tooling
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 661~669
Rapid tooling technique enables us to make dies and molds that produce prototype parts with the correct material at a substantially reduced cost and time. In this study, experiments on selective laser sintering of tungsten carbide-cobalt mixture were carried out to find optimal sintering conditions that will be applied to rapid metal tooling. The experiments were carried out within an air, an argon and a nitrogen atmosphere. Coupons of single layer were sintered at various laser powers, scanning speeds and scan spacings. Very severe oxidation took place within an air atmosphere. The oxidation is reduced significantly within an argon and a nitrogen atmosphere. The thickness of the sintered coupons is increased as the energy density, the laser energy Per unit scanned area, is increased. Several multi-layer sintering experiments were also carried out.
Study on Fluid Flow in Rectangular Duct past
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 670~678
Fluid flow in a rectangular duct with
mitered elbow is measured by 5W laser doppler velocity meter. The fluid flow is also computed by commercial software of STAR-CD for comparison between measured and computed velocity profiles in the duct. Reynolds numbers for the comparison are 1,608 and 11,751 based on mean velocity and hydraulic diameter of the duct. First, the fluid flow of Reynolds number equal to 1,608 is predicted by assumptions of both laminar and turbulent models. But, even though the Reynolds number is less than 2,300~3,000, the computation by turbulent model is closed to the experimental data than that by laminar model. Second, the computation for Reynolds number of 11,751 by turbulent model also predicted the experimental data satisfactorily.
A Study on Effect of Intake Charging Conditions upon NO Emissions in a DI Diesel Engine Using Engine Cycle Simulation
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 679~687
In this study, a cycle simulation using a two-zone model is carried out to investigate the effect of intake charging conditions such as oxygen concentration, temperature and pressure on NO emissions in a DI diesel engine. The model is validated against measurements in terms of cylinder pressure, torque, BSFC and NOx emissions with 2902 cc DI diesel engine. Calculated results can be summarized as follows. The oxygen concentration in the intake charge is decreased with increasing of EGR rate and equivalence ratio. As the intake oxygen concentration is reduced, the combustion pressure and the burned gas temperature decrease and, as a result, NO formation decreases. Also, the results show that as the intake pressure increases and the intake temperature decreases, NO emissions are effectively reduced.
On-line Measurement of Oil Consumption Using Oil Consumption Meter
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 688~694
Several methods were developed for on-line measuring oil consumption in gasoline engine using an oil consumption meter. The oil consumption meter indicates the oil quantity by real-time-measuring the oil level in the sump. In order to measure the oil consumption, the oil consumption meter proposed in this paper requires shorter time, less additional procedures, and shows better results than the traditional drain method. Under steady-state engine-operating conditions, the results obtained through the regression or the difference method show an good agreement with those through the drain method. Under transient engine-operating conditions, on the other hand, good results can be obtained through the reference method.
Sensorless Speed Control of Induction Motor by Neural Network
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 695~704
Generally, induction motor controller requires rotor speed sensor for commutation and current control, but it increases cost and size of the motor. So in these days, various researches including speed sensorless vector control have been reported and some of them have been put to practical use. In this paper a new speed estimation method using neural networks is proposed. The optimal neural network structure was tracked down by trial and error, and it was found that the 8-16-1 neural network has given correct results for the instantaneous rotor speed. Supervised learning methods, through which the neural network is trained to learn the input/output pattern presented, are typically used. The back-propagation technique is used to adjust the neural network weights during training. The rotor speed is calculated by weights and eight inputs to the neural network. Also, the proposed method has advantages such as the independency on machine parameters, the insensitivity to the load condition, and the stability in the low speed operation.
A Study on the Identification and Speed Control of Diesel Engines Using Neural Networks
K-Y kim ; Y-H Yu ;
Journal of the Korean Society of Marine Engineering, volume 26, issue 6, 2002, Pages 705~711