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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
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
Freezing and Melting Phenomena of Urea-water Solution for Diesel Vehicle SCR System
Choi, B.C. ; Seo, C.K. ; Myong, K.J. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 5~10
Urea-SCR system, the selective catalytic reduction using urea as reducing agent, is a powerful technique to reduce nitrogen oxides(NOx) emitted from diesel engines. However, a tank of urea(32.5 wt%)-water solution can be frozen in low ambient temperature levels of below
. The purpose of this study is to understand freezing and melting phenomena of the urea-water solution, and its can be applied to get the urea-water solution from frozen it within 5 minutes after cold start. Factors considered were the type of heater and the urea tank shape. From the results, it was found that melting volume of cartridge heater B during 5 minutes of heating period was 83ml when supplying electric power of 150W. Horizontal heater B, which was put in the narrow bottom space of the tank T1, had fast melting characteristics.
The Effects of Pulsating Flow on Volumetric Efficiency in the Intake and Exhaust System in a Turbocharged Diesel Engine
Kim, K.H. ; Kang, H.Y. ; Koh, D.K. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 11~17
This paper deals with the effects of pulsating flow on volumetric efficiency, which may be generated during the gas exchange procedure, due to piston motion, valve event on intake and exhaust stroke and unsteady flow of turbocharger of a three-cylinder four stroke turbo-charged diesel engine. Consequently, volumetric efficiency affects significantly the engine performance; torque characteristics, fuel economy and further to emission and noise level. As the expansion ratio became larger the engine speed varies and torque increases, the pressure pulsation in an exhaust gas pipe acts as an increasing factor of intake air charging capacity totally. The phase and amplitude of pressure pulsation in the intake system only affects volumetric efficiency favorably, if it is well matched and tuned effectively to the engine. Thus, to verify the exact phase and amplitude of the pressure variation is the ultimate solution for the air-flow ratio assessment in the intake stroke. Some experimental results of pressure diagrams in the intake pipe and gas-flow of turbine in-outlet are presented, under various kinds of operating condition.
Design of a Parallel Hybrid Vehicle Powertrain with Semi-Spherical CVT
Kim, J.Y. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 18~23
Fluid Flow Behaviors around Wedge-shaped Body using Lattice Boltzmann Method
Taher, M.A. ; Jung, H.Y. ; Lee, Y.W. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 24~30
Numerical Investigation of Performance Characteristics for Cooling Tower Axial Fans with Sweep
Oh, K.J. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 31~37
The purpose of this numerical study was to investigate performance characteristics for cooling tower axial fans with sweep. Performance data for the fans with various sweep angles were obtained in terms of the setting angle at a constant flow rate. Viscous flow calculations were carried out to obtain Performance data of the total pressure rise and hydraulic efficiency. A solution of the Ffowcs Williams-Hawkings equations was used to calculate the sound pressure level at three times fan diameter away from the fan. The calculated performance data well represented performance characteristics of the cooling tower axial fan. The total pressure rise and hydraulic efficiency at the same setting angle decreased with sweep angle. Sound pressure level slightly decreased for the fan with a sweep angle of 10 degree. No significant effect of the sweep geometry was found on the sound pressure level.
Development of Rapid Cooling System using Peltier Device
Jang, M.K. ; Lee, G.H. ; Noh, K.C. ; Jeong, Y.D. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 38~42
The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. now then, cooling process spends the most of times in Injection molding cycle time. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to
and had to need 10 minutes for normal operating.
Study on Filtering Method of Acoustic Emission and Characteristic of Signals for the Deformation Process of Steel
Na, E.G. ; Oh, S.H. ; Lee, S.K. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 43~48
The purpose of this study is to show how to eliminate the noises and to obtain the data related with the relationship between AE signal characteristics and mechanical behaviors for the pressure vessel steel. Various kinds of noises are introduced into the AE data in the course of experiments. Accordingly, real AE data have to be obtained after tests. AE test was carried out under four point bending load. Among AE signals, counts and signal strength are used to find out the differences of AE characteristics between the basemetal and weldment. After tests, this paper shows the procedures of filtering the noises against basemetal of the pressure vessel steel to obtain the real data around crack tip. Relationships between plastic zone size and cumulative AE counts are shown also. AE signals were absent within an elastic region, regardless of the specimens. Most of AE signals are produced in the process of plastic deformation. The deformation and fracture modes of basemetal and weldment are quiet different.
Three Dimensional Stress Analysis of Composite Laminates using Stress Functions and Interface Modeling
Kim, H.S. ; Kim, J.Y. ; Kim, J.G. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 49~55
A Primary Study on the Enhancement of Efficiency in the Computer Cooling System using Entrance Tube of Outer Air
Kim, S.H. ; Kim, M.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 56~61
In recent years, since the continuing increase in the capacity in personal computer such as the optimal performance, high quality and high resolution image, the computer system's components produce large amounts of heat during operation. This study analyzes and investigates the ability and efficiency of a cooling system inside a computer by means of central processing unit (CPU) and power supply cooling fan. This research was conducted to enhancement of efficiency of the cooling system inside the computer by making a structure which produces different air pressures in an air inflow tube. Consequently, when temperatures of the CPU and room inside computer were compared with a general personal computer, temperatures of the tested CPU, the room and the heat sink were as low as
respectively. In addition to, revolution per minute (RPM) was shown as low as 250 after 1 hour operation. This research explored the possibility of enhancing the effective cooling of high-performance computer systems.
A Design of Hybrid Type Linear Pulse Motor and Microstep Driver
Kim, M.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 62~67
In this paper we designed a prototype hybrid type linear pulse motor (HLPM) with single side stator structure for low cost. The measurement system which can get the motor characteristics of the HLPM was suggested. The static and dynamic characteristics of the thrust force are measured analyzed. And the microstep drive method is adopted and tested to the drive of prototype HLPM. The thrust waveform is measured respectively to know the differences of the thrust waveform between the microstep drive method and rectangular wave. From the experimental results, it can be confirmed that the repetitive ripple of the thrust force of the prototype HLPM is reduced by taking the microstep drive method.
The Identification of the Magnetic Bearing Control System's Parameters using RCGA
Jeong, H.H. ; Kim, Y.B. ; Yang, J.H. ;
Journal of the Korea Society For Power System Engineering, volume 13, issue 4, 2009, Pages 68~73
The mathematical model has a different response character with the real system because this mathematical model has the modeling errors and the imprecise value of system's parameters. Therefore to find the value of system parameters as possible as near by real value in the model is necessary to design the controlled system. This study concern about the identification method to estimate the parameter for the magnetic bearing system with RCGA(Real Coded Genetic Algorithm). Firstly, we will get the mathematical model from the current amplifier circuit and the magnetic bearing system. Secondly we will get the step response data in this circuit and system. Finally, we will estimate the unknown parameter's value from the data.