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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 30, Issue 8 - Nov 2006
Volume 30, Issue 7 - Nov 2006
Volume 30, Issue 6 - Sep 2006
Volume 30, Issue 5 - Jul 2006
Volume 30, Issue 4 - May 2006
Volume 30, Issue 3 - May 2006
Volume 30, Issue 2 - Mar 2006
Volume 30, Issue 1 - Jan 2006
Selecting the target year
Reliability in marine equipments
Lee, Sang-Tae ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 654~661
Performance Simulation for the Variation of Fuel Injection Nozzle Configurations in Medium Speed Diesel Engine
Kim, Ki-Doo ; Youn, Wook-Hyun ; Kim, Byong-Seok ; Ha, Ji-Soo ; Ahn, Kwang-Hean ; Kim, Ju-Tae ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 662~668
The effects of fuel injection nozzle hole on the NOx emission and fuel oil consumption of medium speed diesel engine HYUNDAI HiMSEN 6H21/32 engine are investigated by engine performance simulation. The results of performance simulation are verified by experimental results of NOx omission fuel oil consumption, cylinder pressure, and heat release rate according to the variation of the number of fuel injection nozzle hole and engine load. The performance simulations are also carried out to optimize the fuel injection nozzle of 6H21/32 engine in respect to the NOx emission and fuel oil consumption. The engine performance measurements are performed to verify the results of performance simulation and to investigate the effects of fuel injection nozzle on engine performance. The results of measurement indicate that significant NOx reduction can be achieved with minimum deterioration in fuel oil consumption by optimizing the geometry of fuel injection nozzle on 6H21/32 engine.
A Study on the Configuration Design and the Performance Analysis of the 20kW HAWT based on BEMT
Kang, Ho-Keun ; Nam, Cheong-Do ; Lee, Young-Ho ; Kim, Beom-Seok ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 669~676
The optimum design and the performance analysis software called POSEIDON for the HAWT (Horizontal Axis Wind Turbine) is developed by use of BEMT, which is the standard computational technique for prediction of power curves of wind turbines. The Prandtl's tip loss theory is adopted to consider the blade tip loss. The lift and the drag coefficient of S-809 airfoil are predicted via X-FOIL and the post stall characteristics of S-809 also are estimated by the Viterna's equations.
All the predicted aerodynamic characteristics are fairly well agreed with the wind tunnel test results. performed by Sommers in Delft university of technology. The rated power of the testing rotor is 20kW(FIL-20) at design conditions. The experimental aerodynamic parameters and the X-FOIL data are used for the power Prediction of the FIL-20 respectively The comparison results shows good agreement in power prediction.
Experimental Study for the Development of New Type Water Ejector
Mun, Soo-Bum ; Choi, Hyun-Kue ; Choi, Jae-Hyuk ; Kwon, Hyung-Jung ; Kim, Kyung-Keun ; Choi, Soon-Ho ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 677~684
An ejector is a fluid transfer device to be used for mixing of fluids, maintaining vacuum, and overcoming a poor suction condition. To date, most ejectors have been made from the casting process. which is time-consuming and high-cost process. Therefore, a new production method of ejectors is desired if any. In this experimental study, we proposed a new type ejector manufactured from the commercial fitting materials and the welding process, which is equipped with an orifice type nozzle. The proposed ejector has a good integrity compared with the conventional ejector because the fittings have manufactured by forging and they have more strength than the casting materials. Furthermore we adopted a multi-opening orifice type nozzle for improving a suction capacity and compared with a single-opening orifice type nozzle. From the experimental results. we confirmed that the multi-opening nozzle had a food suction capacity than the single-opening nozzle and the proposed new type ejector showed higher vacuum than the conventional type ejector in non-load condition. These improved characteristics suggests that a new type ejector by using the commercial fittings opens the feasibility to be adopted in various industry fields and that the increased suction capacity can be achieved by altering the nozzle design of a conventional ejector.
An Experimental Study on the Centrifugal Pump Characteristics in Air-Water Two-Phase Flow
Kim, Sung-Yoon ; Lee, Sang-Il ; Kim, You-Taek ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 685~692
In a general centrifugal pump, if it is operated in a two-phase flow the activity of the impeller usually degrades and occasionally losses its function. However, the effect of break down of centrifugal pump due to entrained air has not been clarified yet. This paper shows the air-water two-phase flow characteristics of closed type and semi-open type impellers. In a sing1e-phase flow, closed-type impeller has higher efficiency and head. But in air-water two-phase flow semi-open type impeller's rates of decreases of efficiency and head are decreased.
Effects of Baffles on Heat Transfer and Friction Factors in a Rectangular Channel
Ahn, Soo-Whan ; Kang, Ho-Keun ; Bae, Sung-Taek ; Song, Min-Ho ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 693~701
The present work investigates the local heat transfer characteristics and the associated frictional loss in a rectangular channel with inclined solid and perforated baffles to obtain the basic design data for gas turbine. Five different geometries of baffles such as 1) solid (without hole), 2) three holes, 3) six holes, 4) nine holes, 5) twelve holes were covered. A combination of two baffles of same overall size is used. The flow Reynolds number is ranged from 28,900 to 70,100. The placement of baffles augments the overall heat transfer greatly by combining both jet impingement and the boundary layer separation. The present results show that the average Nusselt number distribution is strongly dependent on number of holes in the baffle plates, i.e., the average Nusselt number increases with increasing number of holes. The friction factor decreases also with increasing the number of holes. however. its value increases with increasing the Reynolds number.
An Experimental Study of Liquid.Gas Heat Exchange Pipe Inserted Capillary Tube for Room Air-Conditioner
Kim, Jae-Dol ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 702~708
This study shows the experimental characteristics of the double pipe inserted liquid pipe with small diameter in the gas pipe with large diameter for circulating of a liquid of high temperature, pressure and a gas of low temperature, pressure at the same time. So the functions of pipe and pipe's expansion and heat transfer are presented simultaneously. In the result, the temperature of gas refrigerant at the inlet of compressor increased about
by the heat transfer with liquid refrigerant in case of the double pipe. And liquid gas refrigerant which the temperature at the inlet of evaporator decreased about
comparing with the existing type flows into an evaporator COP of the double pipe increased about
comparing with that of the conventional pipe. And the noise of the double pipe at capillary tube is less than that of the conventional type about 3dB. Consequently. it is convinced the superiority of the double pipe in the heat loss and soundproofing aspect.
Effect of Thermal Cycle and Stress on the Intergranular Corrosion in 316 Stainless Steel
Jung, Byong-Ho ; Kim, Moo-Gil ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 709~715
The effects of thermal cycle condition and applied stress on the intergranular corrosion in austenitic 316 type stainless steels were investigated. Specimens were solution-treated at 1100
for one hour and then sensitized in the temperature range of
with a various applied stresses of
. Degree of sensitization. DOS %, was measured through polarization curve by electrochemical DL-EPR test. Microstructural observations were also conducted DOS % increased with an increase of sensitization temperature and/or holding time. Increase of applied stress resulted in increase of DOS % and more corroded surface because of acceleration of intergranular corrosion and fine grain size due to the stress. Cr depleted zone near grain boundary was observed. The amount of depletion was profounded with an increase of sensitization temperature, holding time and applied stress.
carbides were precipitated discontinuously at grain boundary. However, its amount was relatively small in the thermal cycle condition of 800
, 300sec and 4kg/mm
Natural Element Analysis on Macro Elastic Moduli for Materials with Micro-cracks
Kang, Sung-Soo ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 716~723
A meso-scale analysis method using the natural element method is proposed for the analysis of material damage of brittle microcracking solids. The microcracking is assumed to occur along Voronoi edges in the Voronoi diagram generated using the nodal points as the generators. The mechanical effect of microcracks is considered by controlling the material constants in the neighborhood of the micorcracks. The macro elastic moduli of isotropic solids containing a number of randomly distributed microcracks are calculated considering the effect of microcrack closure to demonstrate the validity of the proposed method.
Natural Element Analysis on Micro-cracking Behavior of Brittle Solids
Kang, Sung-Soo ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 724~730
Fracture behavior of brittle solids is closely related to microcracking. A meso-scale analysis method using the natural element method is proposed for the analysis of brittle microcracking solids. The microcracking is assumed to occur along Voronoi edges in the Voronoi diagram generated using the nodal points as the generators. The mechanical effect of microcracks is considered by controlling the material constants in the neighborhood of the microcracks. The meso-analysis method is applied to the simulation of the microcracking behaviors of brittle solids subjected to tensile macrostress. The method is also applied to the analysis of the propagation of a macrocrack accompanied by the coalescence with microcracks formed near the macrocrack-tip.
The Effect of Shot Peening on the Corrosion and Fatigue Crack to SAE5155 Steel
Park, Kyeong-Dong ; Shin, Yung-Jin ; Kim, Dong-Ug ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 731~739
Corrosion and lassitude are very important in the metal construction Currently, the shot peening is used much for removing the defect on the surface, improving the fatigue strength on surface. In this study. the influence of shot peening to the corrosion property were investigated in 3.5% NaCl, 10% HNO3 + 3% HF. 6% FeC13. The immersion test was performed on two kind of specimen(Removed corrosion product. RCP and Continuous immersed specimen: CIS). The immersion periods was 3600hours. Corrosion potential. weight loss, and fatigue crack growth characteristics were investigated. The result, shot peening in corrosion potential showed stable potential. Also, shot peening displayed small Weight loss than un peening. And Fatigue crack resistivity of shot peening in corrosion solution's fatigue crack appeared greatly than un peening.
The Weldability of Aluminum Ball in Electrolyte Injection Hole by Nd:YAG Laser
Kim, Jong-Do ; Yoo, Seung-Jo ; Kim, Jang-Soo ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 740~745
This study suggested the occurrence source of weld-defects and its solution methods in a welding of Electrolyte injection hole by pulsed Nd:YAG laser. In experiment, the ramp down was used in order that solidification crack was removed. Furthermore. shrinkage stress and heat input were reduced by changing of weld trajectory and defocused distance. As a results of a experiment, a sound weld bead shape and crack-free weld bead can be obtained. In conclusion this show that the welding stability is greatly affected by modulation of laser pulse shape for the same laser energy and welding parameters.
RCGA-Based Parameter Estimation and Stabilization Control of an Inverted Pendulum System
Ahn, Jong-Kap ; Lee, Yun-Hyung ; Yoo, Heui-Han ; So, Myung-Ok ; Jin, Gang-Gyoo ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 746~752
This paper presents a scheme for the parameter estimation and stabilization of unstable systems, such as inverted pendulum systems. First a stable feedback loop is constructed for an inverted pendulum system and then its parameters are estimated based on input-output data, a real-coded genetic algorithm(RCGA) and the model adjustment technique. Then, a PI-type LQ control scheme is designed based on the estimated model. The performance of the proposed algorithm is demonstrated through a set of simulation and experiment.
PID Controller Tuning Rules for Integrating Processes with Time Delay
Lee, Yun-Hyung ; So, Myung-Ok ; Hwang, Seung-Wook ; Ahn, Jong-Kap ; Kim, Min-Jung ; Jin, Gang-Gyoo ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 753~759
Integrating processes are frequently encountered in process industries. In this paper, new tuning formulae of the PID controllers for set-point tracking and load disturbance rejection are presented for integrating processes involving time delay. First, the controller parameter sets are tuned using a real-coded genetic algorithm (RCGA) such that performance criterion(IAE, ISE or ITSE) is minimized. Then, tuning rules are addressed using tuned PID parameter sets. tuning model and another RCGA. The performances of the proposed rules are tested on two processes.
A Fuzzy PID Controller Type Autopilot System for Route-Tracking of Ships
Kim, Jong-Hwa ; Ha, Yun-Su ; Lee, Byung-Kyul ;
Journal of the Korean Society of Marine Engineering, volume 30, issue 6, 2006, Pages 760~769
This paper proposes an autopilot system using a fuzzy PID controller to satisfy performances required for the automatic navigation of ships under various marine circumstances. The existing autopilot system using a PD type controller has difficulties in eliminating a steady-state error and compensating nonlinear characteristics of ships. The autopilot system using the proposed fuzzy PID controller has a self-tuning ability, an ability to compensate nonlinear characteristics, and an ability to turn at constant angular velocity. Therefore. it can naturally make a steady-state error zero, compensate nonlinear dynamic effect of ships, have an adaptability to parameter variation owing to shallow water effect, and have an ability to turn ship's course rapidly without overshoot through procedures of acceleration, constant, and deceleration of angular velocity for large course-changing.