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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 18, Issue 6 - Dec 2014
Volume 18, Issue 5 - Oct 2014
Volume 18, Issue 4 - Aug 2014
Volume 18, Issue 3 - Jun 2014
Volume 18, Issue 2 - Apr 2014
Volume 18, Issue 1 - Feb 2014
Selecting the target year
Effects of Bio-diesel blending rate on the Combustion and Emission Characteristics in a Common Rail Diesel Engine with EGR rate
Yoon, Sam-Ki ; Choi, Nag-Jung ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 5~11
DOI : 10.9726/kspse.2014.18.2.005
The purpose of this study is to investigate the specific characteristics of combustion and exhaust emissions on a 4-cylinder common rail diesel engine as EGR rate and the rate of blended bio-diesel was altered. Bio-diesel fuel which is a sort of alternative fuels can be adapted to diesel engine directly without modifying. This study was performed to 2000rpm of engine speed with torque 30Nm while EGR rate and the rate of blended bio-diesel was changed. Decreasing combustion pressure and increasing the rate of heat were occurred when we had changed the EGR rate on the 20% of bio-diesel blended diesel fuel. The maximum pressure of combustion and the IMEP became higher as the EGR rate and the rate of blended bio-diesel were changed. Exhaust gas temperature was increased the higher rate of the blended bio-diesel under the fixed EGR rate. However, it went down as the EGR rate increased. The amounts of CO and Soot were reduced with increasing the rate of the blended bio-diesel without changing EGR rate and raised with increasing of the EGR rate. On the fixed EGR rate, NOx was increased along with growing the rate of the bio-diesel. On the other hand, it was decreased while EGR rate were going up.
Heat Transfer and Friction in Rectangular Convergent Channels with Ribs on One Wall
Kim, Won-Cheol ; Lee, Myung-Sung ; Bae, Sung-Taek ; Ahn, Soo-Whan ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 12~18
DOI : 10.9726/kspse.2014.18.2.012
The local heat transfer of developed turbulent flows in the stationary ribbed rectangular convergent channels has been investigated experimentally. The rectangular convergent channels with one ribbed surface only have the inclination of
at which the ribbed wall is manufactured with a fixed rib height (e) of 10 mm and the ratio of rib spacing (p) to height (e) =10. The measurement was conducted within the range of Reynolds numbers from 15,000 to 89,000. The local heat transfer characteristics of the rectangular convergent channels are quite different from those of the ribbed square straight channel.
A Study on Heat Transfer Characteristics of H-120 Class Fire Damper for Offshore Structures
Jang, Sung-Cheol ; Lee, Jong-Hwan ; Lee, Chi-Woo ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 19~24
DOI : 10.9726/kspse.2014.18.2.019
This research conducts CAE analysis of fire damper and design of damper controlling system. The prediction of the design heat transfer was done the answer of fire damper could be obtained by using continuity equation of damper controlling and orthogonal array. Through the design analysis of optimal offshore construction, new fire damper of H-120 class was designed. Accordingly, this equipment will be tested in actual offshore construction. Finally, we could obtain fire damper of optimal design with orthogonal array. With the CAE results of this research, The offshore plant will obtain eco-friendly fire damper with a method to select optimal condition of fire damper with orthogonal array.
Heat Transfer and Pump Consumption Power of Indirect Refrigeration System Using CO
as a Secondary Refrigerant
Yoon, Jung-In ; Choi, Kwang-Hwan ; Son, Chang-Hyo ; Yi, Wen-Bin ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 25~30
DOI : 10.9726/kspse.2014.18.2.025
In this paper, the heat transfer coefficient and pump consumption power of indirect refrigeration system using
as a secondary refrigerant were investigated experimentally. First, from the comparison of pump consumption powers of existing brines(EG, PG, EA etc.) and
as secondary refrigerants at the same experimental conditions, PG and
show the highest and lowest power, respectively. Second, the heat transfer coefficient of
is the highest, but PG is the lowest among other secondary refrigerants. From the above results, it is confirmed that
as the secondary refrigerant has excellent characteristics when comparing to existing brines. Thus, it is concluded that
is applicable as the secondary refrigerant of indirect refrigeration system.
Endurance of Pneumatic Valve with a Multi-bender PZT Actuator
Yun, So-Nam ; Park, In-Sub ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 31~36
DOI : 10.9726/kspse.2014.18.2.031
In this paper, pneumatic valve which consists of valve body, valve controller, nozzle and a multi-bender PZT actuator was suggested and fabricated. The fabricated pneumatic valve was experimented for performance evaluation. From the experimental results, we know that the flow rate of the suggested valve is 23 lpm at the pressure difference of 1bar and the maximum flow rate is 30 lpm at the pressure difference of 4 bar. The flow rates after endurance test of 9.8 million were 22.57 lpm and 28.62 lpm at the pressure difference of 1bar and 4bar, respectably. Finally, it was verified that the B10 life of the suggested pneumatic valve is over 50 million.
Polarization Characteristics of Heat-treated Ni-based Self-flux Alloy Coating in Alkaline Solution
Kim, Tea-Yong ; Kim, Jea-Dong ; Kim, Yeong-Sik ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 37~42
DOI : 10.9726/kspse.2014.18.2.037
The purpose of this paper is to investigate polarization characteristics of heat-treated Ni-based self-flux alloy coating in alkaline solution. Ni-based self-flux alloy powder was sprayed to a steel substrate using flame spray process, and heat treatments were performed in a vacuum furnace at
. After heat treatments, corrosion tests were carried out using potentiostat/galvanostat at solution with pH 8 and pH 13. Corrosion potential(Ecorr) and corrosion current density(Icorr) could be analyzed from polarization curve. Anticorrosive effect of heat-treated coating at solution with pH 8 was relatively greater than at solution with pH 13. Heat-treated coating at
showed the greatest anti-corrosion characteristics in alkaline solution.
Study of Nanoparticle Effect on Durability of Carbon fiber/Epoxy Resin Composites in Moisture Environment
Ahn, Seok-Hwan ; Choi, Young-Min ; Moon, Chang-Kwon ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 43~49
DOI : 10.9726/kspse.2014.18.2.043
This study has been investigated on the durability of carbon fiber/epoxy composites (CFRP) in moisture environment. The carbon fiber/epoxy composites were modified to use the nanoparticles such as carbon nanotubes and titanium oxide. These hybrid composites were exposed to moisture environment for a certain period of time. Weight gain according to immersion time, quasi-static tensile test and micro-graphic characterization were investigated on the samples exposed to moisture environment. Consequently, the weight gains increased with increasing immersion time and weight gain of the hybrid composites was lower than the one of CFRP through the whole immersion time. The tensile strengths decreased with increasing immersion time and tensile strengths of the hybrid composites were higher than the one of CFRP through the whole immersion time. The CFRP were observed more degraded than hybrid compositess in moisture environment. Therefore, it was concluded that the addition of nanoparticles in CFRP could lead to improve the durability in moisture environment.
Mechanical Property and Process Variables Optimization of Tube-to-Tube Friction Welding for Steel Pipe with 36 mm External Diameter
Kong, Yu-Sik ; Park, Young Whan ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 50~56
DOI : 10.9726/kspse.2014.18.2.050
Friction welding is a very useful joining process to weld metals which have axially symmetric cross section. In this paper, for the friction welding with tube-to-tube shape, the feasibility of industry application was determined using analyzing mechanical properties of weld and optimized welding variables was suggested. In order to accomplish this object, rotating speed, friction heating pressure, and friction heating time were selected as the major process variables and the experiment was performed in three levels of each parameter. Weld characteristic was investigated in terms of weld shape and metal loss, and 7mm of metal loss was regarded as the optimal metal loss. By tensile test, tensile strength and yielding strength was measured and fracture was occurred at base metal. In order to optimize the welding condition, fitness function was defined with respect to metal loss and yielding strength and the fitness values for each welding condition could be calculated in experimental range. Consequently, we set the optimal welding condition as the point which had maximum value of fitness function. As the result of this paper the optimal welding variables could be suggested as rotating speed was 1300 rpm, friction heating pressure was 15 MPa, and friction heating time was 10 sec.
Development of Analysis Program of Dynamic Characteristic for the Propulsion Shafting System
Ha, Jeong-Min ; Lee, Jeong-Myeong ; Lee, Jeong-Hoon ; Kim, Yong-Whi ; Ahn, Byeong-Hyun ; Choi, Byeong-Keun ; Kim, Won-Chul ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 57~61
DOI : 10.9726/kspse.2014.18.2.057
Due to the changes of marine transportation industry, it requires ship in larger scale and high speed. In order to operate efficiently, the engine should be work in high power and high horse power. The increase of the number of the propeller blades and the pitch of the screw and the weight, vibration of shafting problems occurs. To evaluate the safety of the system through analyzing the dynamic characteristics propulsion shafting system, was used to prove or to verify the Lalanne & Ferraris model validation.. It indicates that the Program through Campbell diagram and Critical speed map, Root rocus map, to ensure the reliability of the experimental model.
Marco and Microscopic Observations of Fatigue Crack Growth in Friction Stir Welded 7075-T651 Aluminum Alloy Plates
Kong, Yu-Sik ; Kim, Seon-Jin ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 62~69
DOI : 10.9726/kspse.2014.18.2.062
In this paper, in order to investigate the effects of marco and microscopic observations of fatigue crack growth in friction stir welded (FSWed) 7075-T651 aluminum alloy plates, fatigue crack growth tests were performed under constant amplitude loading condition at room temperature with three different pre-cack locations, namely base metal (BM-CL) and two kinds of pre-crack locations in welded joints, weld metal (WM-CL) and heat affected zone (HAZ-CL) specimens. The fatigue crack growth behavior of FSWed 7075-T651 aluminum alloy plates were discussed based on the marco and microscopic fractographic observations. The marcoscopic aspects of surface crack growth path for BM-CL and HAZ-CL specimens indicate relatively straight lines, however, the crack growth paths of WM-CL specimens grow first straight and by followed toward the TMAZ and HAZ. The microscopic aspects of fatigue fracture for BM-CL and HAZ-CL specimens indicate typical fatigue striation, but WM-CL showed intergranular fracture pattern by micro structural changes of FSW process.
Effect of Aging Treatment on Pitting Corrosion of Super Duplex Stainless Steel Weld Metal
Lee, Jae-Hyoung ; Seo, Gi-Jeong ; Jung, Byong-Ho ; Kang, Chang-Yong ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 70~76
DOI : 10.9726/kspse.2014.18.2.070
A specimen of weld metal was prepared by GTA welding with weld wire of super duplex stainless steel. Aging treatment was conducted for the sample at the temperature range of 700 to
for 5 to 300 minutes. The effect of aging temperature and time to pitting corrosion of weld metal has been investigated and the results were derived as follows. The volume fraction of
phase tends to increase with an increase of aging temperature and time. Pitting potential Ep representing pitting corrosion was found to tend to decrease with an increase of aging time at 700 to
. And most of the pits formed near the
-phase in the ferrite and seemed to propagated to austenite.
The Effects of Parameter Changes on the Properties of an Air Spring
Jang, Ji-Seong ;
Journal of the Korea Society For Power System Engineering, volume 18, issue 2, 2014, Pages 77~82
DOI : 10.9726/kspse.2014.18.2.077
The air spring is widely used in various fields such as a suspension system and an anti-vibration system because the natural frequency is kept constant regardless of the change in the load, spring constant is easy to change, and, vibration and shock isolation performance are excellent. The purpose of this study is to derive a nonlinear governing equation of an air spring, to analyze the effect of the various parameters on the dynamic stiffness of the air spring, and, to suggest a more efficient design method of an air spring system. In order to do so, this study investigates the impact of all the parameters that could affect the dynamic stiffness of the air spring while changing the excitation amplitude and the frequency with a developed governing equation.