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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korea Society For Power System Engineering
Journal Basic Information
Journal DOI :
The Korea Society for Power System Engineering
Editor in Chief :
Volume & Issues
Volume 13, Issue 6 - Dec 2009
Volume 13, Issue 5 - Oct 2009
Volume 13, Issue 4 - Aug 2009
Volume 13, Issue 3 - Jun 2009
Volume 13, Issue 2 - Apr 2009
Volume 13, Issue 1 - Feb 2009
Selecting the target year
Trend of Waste Exhaust Heat Recuperation Systems for Vehicles
Kim, K.S. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 1~6
Introduction on Basic Study and Applied Field for Diesel Spray
Yeom, J.K. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 7~12
A Basic Study of the Behavior Characteristics of Diesel Spray and Natural-gas Jet
Yeom, J.K. ; Kim, M.C. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 13~21
This basic study is required to examine spray or jet behavior depending on fuel phase. In this study, analyses of diesel fuel(n-Tridecane,
) spray and natural gas fuel(Methane,
) jet under high temperature and pressure are performed by a general-purpose program, ANSYS CFX release 11.0, and the results of these are compared with experimental results of diesel fuel spray using the exciplex fluorescence method. The simulation results of diesel spray is analyzed by using the combination of Large-Eddy Simulation(LES) and Lagrangian Particle Tracking(LPT) and of a natural gas jet is analyzed by using Multi-Component Model(MCM). There are two study variables considered, that is, ambient pressure and injection pressure. In a macroscopic analysis, the higher ambient pressure is, the shorter spray or jet tip penetration is at each time after start of injection. And the higher injection pressure is, the longer spray or jet tip penetration is at each time after start of injection. When liquid fuel is injected, droplets of the fuel need some time to evaporate. However, when natural gas fuel is injected, the fuel does not need time to evaporate. Gas fuel consists of minute particles. Therefore, the gas fuel is mixed with the ambient gas more quickly at the initial time of injection than the liquid fuel is done. The experimental results also validate the usefulness of this analysis.
A Performance Analysis of a Spark Ignition Engine Using Gasoline, Methanol and M90 by the Thermodynamic Second Law
Kim, S.S. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 22~28
Comparative Analysis on Combustion Characteristics of Diesel Oil and Biodiesel Blends in Dl Diesel Engine (Using Soybean Oil)
Lim, J.K. ; Choi, S.Y. ; Cho, S.G. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 29~34
Recently, we have a lot interest in a sudden rise of oil prices and a change weather for the earth warmming, so, development of new alternative fuels need in order to spare fossil fuel and reduce exhaust emissions for air pollution prevention. Biodiesel, which can be generated from natural renewable sources such as new or used vegetable oils or animal fats, may be used as fuel in diesel engine of compression ignition engine. In this paper, the combustion characteristics between neat diesel oil and biodiesel blends(10 vol.% biodiesel and 20 vol.% biodiesel) were tested using four stroke, direct injection diesel engine, especially this biodiesel was produced from soybean oil at our laboratory. This analysis showed that cylinder pressures, the rate of pressure rises and the rate of heat releases were decreased as the blending ratios of biodiesel to diesel oil increased because of lower heating value of biodiesel in spite of increased oxygen content in biodiesel.
Thermal Stress Analysis of Piping Systems in Steam-driven Power Engines
Kim, C.H. ; Chung, H.T. ; Bae, J.S. ; Jung, I.S. ; Lee, S.S. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 35~42
The piping systems in the steam-driven power engines lie under the cyclic condition of thermal expansion and contraction by superheated steam. These phenomena might cause some severe damages on the pipes and the accessory devices. To avoid these damages, the calculation of the proper strength and the consideration of the reduced resultant forces on the materials are needed. In the present study, numerical investigations on the effects of the thermal deformation of the industrial piping system were performed with comparison of the design data. Commercial software, ABAQUS with the thermal-fluidic loadings based on the design conditions was used for the thermal stress analysis of the piping system. From the analysis of the initially-designed pipe supporters, the rearrangement was suggested to improve the piping design.
Robust Torque Control for an Internal Combustion Engine with Nonlinear Uncertainty
Kim, Y.B. ; Kim, J.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 43~50
If an internal combustion engine is operated by consolidated control, the minimum fuel consumption is achieved satisfying the demanded objectives. For this, it is necessary that the engine is operated on the ideal operating line which satisfies minimum fuel consumption. In this context of view, there are many tries to achieve given object. However, the parameter in the internal combustion engines are variable and depend on the operating points. Therefore, it is necessary to cope with the uncertainties such that the optimal operating may be possible. From this point of view, this paper gives a controller design method and a robust stability condition for engine torque control which satisfies the given control performance and robust stability in the presence of physical parameter perturbation. Exactly, the present paper considers a robust stability of this 2DOF servosystem with nonlinear type uncertainty in the engine system, and a robust stability condition for the servosystem is introduced. This result guarantees that if the plant uncertainty is in the permissible set defined by the given condition then a gain tuning can be carried out to suppress the influence of the plant uncertainties.
Combustion Characteristics of Biodiesel Fuel as an Alternative Fuel for a D.I. Diesel Engine(2)
Jang, S.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 51~56
Recently, lots of researchers have been attracted to develop various alternative fuels in diesel engine. The use of biodiesel fuel(BDF) is an effective way of substituting diesel fuel in the long run. But biodiesel fuel can affect the performance and emissions in diesel engine because it has different chemical and physical properties from diesel fuel. In this study, to investigate the combustion characteristics of biodiesel fuel as an alternative fuel for D.I. diesel engine, experiments were carried out at the three-cylinder, four stroke D.I. diesel engine with T/C. As a result, shorter ignition delays were observed for the biodiesel blend cases relative to the diesel oil. The pick value of premixed combustion for the rate of heat release is increased with decreasing C.F.W. temperature.
Characteristics of Unsteady Flows in a Semi-Induction System by a Variable Volume Helmholtz Resonator
Kang, K.E. ; Kim, K.H. ; Kang, H.Y. ; Koh, D.K. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 57~62
Unsteady flows in a semi-induction system was investigated to verify their characteristics. A semi-induction system was designed and made to verify the Sow characteristics in an intake system. To attain an intact wave of an intake pulse, a single semi-intake system was adopted as a test rig. The system consists of an intake pipe and a rotary valve as a pulse generator, and a variable volume Helmholtz resonator. The variable volume Helmholtz resonator was mounted in the intake pipe to enhance a breathing capacity and engine performance. The phase and amplitude of the pulsating flow in an unsteady flow system were found to affect the charging capacity significantly. The behavior of pressure wave, their phase and amplitude were investigated in various regions. Some of the results obtained from experiments were described.
An Experimental Study of Operating Characteristics on Fouling Auto Removal Apparatus of Multi Pass Type Heat Exchanger using Ejector
Kim, J.D. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 63~69
The experiment was performed to check operating characteristics of fouling auto removal apparatus for multi pass type heat exchanger using ejector. The results showed as following. The ejector suction flow rate increased with the head of operating pump of ejector. Proper suction flow rate showed
for ball collection in case of pump head 35~50m. The head of ejector outlet pipe is below 4.1m in case of 40m, the head of operating pump of ejector to confirm ejector suction flow rate 8.4m3/h. Lattice space of ball separator is allowed 6~10.3mm in ranges of ball diameter are 15~25mm and when mass flow of cooling water is 3.0m/sec. Average of passing time of balls is 1.2~2.8sec depend on the velocity of flow and the size of balls.
Performance Analysis of a Carbon Dioxide(R744) Two-Stage Compression and One-Stage Expansion Refrigeration Cycle
Roh, G.S. ; Son, C.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 70~75
In this paper, cycle performance analysis of R744(
) two-stage compression and one-stage expansion refrigeration system is presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include superheating degree, compressor efficiency, gas cooling pressure, mass flowrate ratio, outlet temperature of gas cooler and evaporating temperature in the carbon dioxide two-stage refrigeration cycle. The main results were summarized as follows : The cooling capacity of two-stage compression and one-stage expansion refrigeration system increases with the increasing superheating degree, compressor efficiency and gas cooling pressure, but decreases with the increasing mass flowrate ratio and evaporating temperature. The compression work of two-stage compression and one-stage expansion refrigeration system increases with the increasing superheating degree, outlet temperature of gas cooler, gas cooling pressure and evaporating temperature, but decreases with the increasing compressor efficiency and mass flowrate ratio. The COP of two-stage compression and one-stage expansion refrigeration system increases with the increasing compressor efficiency, but decreases with the increasing superheating degree, gas cooling pressure, mass flowrate ratio and evaporating temperature. Therefore, superheating degree, compressor efficiency, gas cooling pressure, mass flowrate ratio, outlet temperature of gas cooler and evaporating temperature of R744(
) two-stage compression and one-stage expansion refrigeration system have an effect on the cooling capacity, compressor work and COP of this system.
A Study on the Performance Prediction of Low Temperature Thermal Desorption System
Lee, C.T. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 76~81
Thermal desorption systems are designed to remove organic compounds from solid matrices such as soils, sludges and filter cakes without thermally destroying them. It is a separation technology, not a destruction technology. Since it is a thermal process, there is a common belief that temperature is the only significant parameter to be monitored. While it is true that better removal efficiencies are usually achieved at higher temperatures, other factors must be considered. Since the process is governed by mass transfer, heating time and the amount of mixing are also key parameters in optimizing removal efficiency. Thermal desorption have been successfully used for just about every organic contaminant found to date. It has also been used to remove mercury. In the present study, the numerical simulation has been performed to investigate the characteristics of heat transfer of LTTD(low temperature thermal desorption). The commercial software, AMESIM was applied for analyzing the heat transfer process in the LTTD.
Flow Field Measurements in a Torque Converter (II)
Yoo, S.C. ; Jang, S.K. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 82~87
LDV measurements were conducted on the planes between impeller blades of torque converter. The flow fields are extremely complex because they contain unsteady viscous three-dimensional flows. Besides of their complexity, the difference in rotor speeds between the impeller and turbine compound the flow effects. The good spatial resolution of the LDV allows measurements of the instantaneous flow structures within the impeller passage, yielding valuable information about the production automotive torque converter in realistic operating conditions. It was found that the mass flow rates are strongly related with the internal flow characteristics of torque converter.
Study on Vibration Characteristics after Applying Variable Speed Control to Constant Speed Fans used in a Power Plant
Cho, C.W. ; Song, O.S. ; Yang, K.H. ; Kim, G.Y. ; Cho, S.T. ; Moon, H.D. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 88~94
In this paper, vibration characteristics after applying variable speed control to fans with a rated speed used in a power plant are studied by performing experiments and analyzing finite element models. Then the campbell diagram is presented to verify the reason of the abnormal vibration measured from fan structure during variable operation of Forced Draft Fan & Induced Draft Fan. According to results, it is found that amplitude of acceleration increases abruptly when a 2X harmonic component meets the natural frequency of fan rotor. Therefore it is very important thing that investigate exactly dynamic characteristics for the rotor at variable speed zone before applying variable speed control to a rotor with a rated speed.
Investigation of the Coil Deforamtion of the Gas Turbine Generator Rotor Using Finite Element Analysis
Yun, W.N. ; Park, H.K. ; Kang, M.S. ; Kim, J.S. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 95~101
The generator for gas turbine power generation consists of the rotor which generates magnetic field, the winding coil which is the path for the field current and the wedge and retaining ring which prevents the radial movement of the coil. Relatively severe deformation was observed at the coil end section during the inspection of the generator for peaking-load operation, and the thermal-electricity and the centrifugal force were evaluated by the simple modeling of the windings to find the cause. But the simulation stress was not sufficient to induce the coil plastic deformation. The analysis result seems to be applicable to the base-load generators which runs continuously without shut down up to a year, but there had been more deformation than simulated for the generator which is started up and shut down frequently. The cause of the coil deformation was the restriction of the expansion and shrinkage. The restriction occurs when the winding coil shrinks, and the stress overwhelms the yield stress and cause the plastic deformation. The deformation is accumulated during the start-ups and shut-downs and the thermal growth occurs. The factors which induce the coil restriction during the expansion and shrinkage should be reduced to prevent the unallowable deformation. The resolutions are cutting off the field current earlier during the generator shut-down, modifying the coil end section to remove the stress concentration and making the insulation plate inserted between the coil end section and the retaining ring have the constant thickness.
Study on Scoring of Hypoid Gear Set in Bus with Retarder
Yang, J.H. ; Kim, Y.J. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 102~109
A retarder, as a supplementary brake system that is not friction-based, is frequently used in heavy-duty vehicles generally to slow the vehicles down on inclines. The electric retarder mainly used in a heavy-duty bus is generally placed between the transmission and the axle. The rotor inside the retarder system is attached to the axle. The operation of the retarder within a driven vehicle generates reverse torque due to coast driving force on hypoid gears in the differential gear system. By the reverse torque, scoring or scuffing on the hypoid gear teeth may directly occur. The scoring may be generated due to excessive contact stresses on the tooth surface. In this study, tooth contact stresses and contact patterns were analysed in order to investigate on the tooth scoring phenomenon using a finite element analysis program T900 in which the Hertzian contact stress formula was taken. Backlash, wear and surface finish were considered in the finite element simulation on the scoring.
A Study on the Output Characteristic of Vacuum Booster
Lee, C.T. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 110~116
In the present study, we proposed a simulation model of vacuum booster with AMESIM software to predict the output characteristic. And we performed the sensitivity analysis of output characteristic with main design parameters, such as diaphragm diameter. All of these parameters are main design parameters in the procedure of vacuum booster design. The simulation results of this paper offer qualitative information of vacuum booster output. Therefore, the simulation results of this paper will be used effectively for the design procedure of vacuum booster in the industrial field.
Shape Design of the U-Type Wedge of the Rail Clamp for a Container Crane
Han, D.S. ; Han, G.J. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 117~122
The wedge type rail clamp compresses the rails with small clamping force at first, and with large clamping force when the wind speed increases because of the wedge working. If the supporter is not installed in the rail clamp with V-type wedge when the wind speed increases more and more, the structure will occur overload which leads the structure to fracture. But in the clamp with U-type wedge the supporter is not necessary because the tangential angle of the wedge increases as the sliding distance increases. The proper shape of U-type wedge is determined by the initial clamping force and the tangential angle of the wedge. Accordingly we, first carry out the finite element analysis in order to analyze the relation between the sliding distance and the wedge angle. Next we suggest the proper shape of U-type wedge as analyze the relation between the radius of curvature and the sliding distance.
Impact and Wear Behavior of Side Plate of FRP Ship
Kim, H.J. ; Kim, J.D. ; Koh, S.W. ; Kim, Y.S. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 123~128
The effects of temperature and initial crack length on the impact fracture behavior for the side plate material of FRP ship were investigated. And the effects of the counterpart roughness and sliding distance on the volumetric wear of same material were investigated as well. Impact fracture toughness of GF/PE composites displayed maximum value when the temperature of specimen is room temperature and
, and with decreasing the temperature of specimen, impact fracture toughness decreased. Impact fracture energy of GF/EP composites decreased with increasing the initial crack length of specimen, and this value decreased rapidly when the temperature of specimen is lowest,
. It is believed that sensitivity of notch on impact fracture energy were increased with decreasing the temperature of specimen. With increasing the sliding distance, the transition sliding distance, which displayed different aspect on the friction coefficient and the volumetric wear loss, were found out. Counterpart roughness had a big influence on the wear rate at running in period, however the effect of counterpart roughness became smaller with sliding speed increase in. Volumetric wear loss were increased with increasing the applied load and the counterpart roughness.
A Study on the Synchronous Control of Two Motor Cylinders with Skew Disturbance
Byun, J.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 6, 2009, Pages 129~136
A motor cylinder is widely used as an apparatus for transportation of a small scale load. It is, however, difficult for only one motor cylinder to transfer a large scale load such as a weir. The large scale load is transferred by two motor cylinders which are mounted on right and left of load itself. In this case, the displacement difference generated between two motor cylinders, namely, the synchronous error has a bad influence on the transportation. In this study, a synchronous control system is designed to restrain synchronous error caused by skew disturbance. The control system is composed of two disturbance observers and one synchronous controller. Each disturbance observer is designed to restrain the skew disturbance. And the synchronous controller is designed to achieve stable and accurate synchronization. Finally, the simulation results show that the designed control system is effective for the skew disturbance which lead to synchronous error.