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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of ILASS-Korea
Journal Basic Information
Journal DOI :
Institute for Liquid Atomization and Spray Systems-Korea
Editor in Chief :
Volume & Issues
Volume 20, Issue 4 - Dec 2015
Volume 20, Issue 3 - Sep 2015
Volume 20, Issue 2 - Jun 2015
Volume 20, Issue 1 - Mar 2015
Selecting the target year
Experimental Investigation on the Thermal Performance Enhancement of Cooling System for Vehicles using Water/Coolant-Based Al
Park, Y.-J. ; Kim, H.J. ; Lee, S.-H. ; Choi, T.J. ; Kang, Y.J. ; Jang, S.P. ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 65~69
DOI : 10.15435/JILASSKR.2015.20.2.65
In this study, the thermal performance of vehicle's cooling system is experimentally investigated using the water/coolant-based
nanofluids as working fluids. For the purpose, the water/coolant-based
nanofluids are prepared by twostep method with gum arabic. In order to obtain the well-suspended nanofluids, the agglomerated
nanoparticles are precipitated using centrifugal force and the experiments are performed with supernatant of them. The thermal conductivity is measured by transient hot wire method and the thermal conductivity of nanofluids is enhanced up to 4.8% as compared to that of base fluids. Moreover, the cooling performance of water/coolant-based
nanofluids is evaluated using vehicle's engine simulator under the constant RPM condition. The results show that the cooling performance of automobile engine increases up to 5.9% using prepared nanofluids. To investigate the effect of nanofluids on exhaust gas, the
emission is measured during the operation with respect to time and 10.3% of
emission is decreased. The experimental results imply that the water/coolant-based
nanofluids might be used as a next-generation vehicles' coolant
Effect of the Swirl Number of Spinner on the Exhaust Air of the Gun Type Burner
Ko, Dong Guk ; Yoon, Suck Ju ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 70~75
DOI : 10.15435/JILASSKR.2015.20.2.70
Swirl flow in the gun type burner has an impact on the stabilization of the flame, improvement of the combustion efficiency. The swirl flow is created by the spinner which is inside the airtube that guide the combustion air. Gun type burner has generally the inner devices composed electronic spark plug, injection nozzle, combustion device adaptor, and spinner. These inner components change the air flow behavior passing through airtube. So, this study conducted the measurement using by hot-wire anemometer and analyzed effect of the swirl number of spinner on the exhaust air of gun type burner. Turbulence characteristics come up in this study was mean velocity, turbulence intensity, kinetic energy, shear stress and flattness factor of the air flow with the change of the distance of axial direction and tangential direction from the exit of the airtube.
A Study on the Exhaust Flow Characteristics of the Gun Type Burner according to the Ratio of Airtube Diameter
Ko, Dong Guk ; Yoon, Suck Ju ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 76~81
DOI : 10.15435/JILASSKR.2015.20.2.76
Swirl flow has an impact on the stabilization of the flame by the recirculation flow, improvement of the combustion efficiency. The swirl flow in the gun type burner is created by the spinner which is inside the airtube that guide the combustion air. Burner has generally the combustion device composed electronic spark plug, injection nozzle, combustion device adaptor, and spinner. These inner components change the air flow behavior passing through airtube. So, this study analyzed exhaust flow characteristics of the gun type burner according to the ratio of airtube diameter. Turbulence characteristics by the spinner was mean velocity, turbulence intensity, kinetic energy, shear stress and flattness factor of the air flow of axial direction and tangential direction from the exit of the airtube.
Spray Characteristics of Air-assisted Vortex Nozzle at Low Pressure Condition
Kim, Woojin ; Subedi, Bimal ; Choi, Jang-Soo ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 82~87
DOI : 10.15435/JILASSKR.2015.20.2.82
A nozzle with vortex generator was used to develop the low pressure nozzle with high atomization performance and the nozzle atomized the liquid by centrifugal shear forces. In order to analyze the atomization characteristics, a shadowgraphy method was used and the measurement of droplet size was performed by using laser diffraction analyzer. The liquid injection pressure was fixed as 0.03 bar which is very low pressure and the gas injection pressures were changed from 0 bar to 2.0 bar. As a result, the breakup was achieved at the air injection pressure of 0.25 bar and over. The nozzle with the orifice diameter of 0.4 mm and the orifice gap of 0.25 mm presented small droplet diameters under 50 at the air injection pressure of 0.75 bar.
An Experimental Study on Spray Characteristics of Bio-diesel fuel in Three Injectors with Different Operating Mechanism for Common-rail System
Sung, Gisu ; Kim, Jinsu ; Jeong, Seokchul ; Lee, Jinwook ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 88~94
DOI : 10.15435/JILASSKR.2015.20.2.88
Recently, exhaust gas regulation has been gradually strengthened due to depletion of fossil fuels and environmental problem like a global warming. Due to this global problem, the demand for eco-friendly vehicle development is rapidly increasing. A clean diesel vehicle is considered as a realistic alternative. The common-rail fuel injection system, which is the key technology of the clean diesel vehicle, has adopted injection strategies such as high pressure injection, multiple injection for better atomization of the fuel. In addition, the emission regulations in the future is expected to be more stringent, which a conventional engine is difficult to deal with. One of the way for actively proceeding is the study of alternative fuels. Among them, the bio-diesel has been attracted as an alternative of diesel. So, in this study, spray characteristics of bio-diesel was analyzed in the common-rail fuel injection system with three injectors driven by different operating mechanism.
A Study for Improving Spray Uniformity of the SECFR System for Vehicle Applications
Shon, J.W. ; Woo, S.C. ; Kim, S.G. ; Lee, K.H. ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 95~100
DOI : 10.15435/JILASSKR.2015.20.2.95
Lower recirculated gas temperature at EGR system reduces NOx and PM emissions. However, EGR Cooler can be polluted by PM generated from recirculated EGR gas, and it reduces cooling efficiency and the amount of EGR gas simultaneously. The SECFR(Steam EGR Cooler Fouling Remover) system which uses the evaporated washer fluid steam caused by high temperature of EGR gas was manufactured for removing fouling generated on the cooler surface. Since an injection pressure of wind shield washer fluid in the vehicle is approximately 0.5 bar, it is not enough to atomize the injected washer fluid. Thus, it is necessary to apply a method to atomize the washer fluid. In this study, the impinging plate was used to promote the atomization of spray washer fluid for the purpose of apply SECFR system to vehicles and measured the DAR(Droplet Area Ratio) and DUI(Droplet Uniformity Index) through the spray visualization.
Analysis of Risk Assessment Factors for Gas leakage and Dispersion in Underground Power Plant
Choi, Jinwook ; Li, Longnan ; Park, Jaeyong ; Sung, Kunhyuk ; Lee, Seonghyuk ; Kim, Daejoong ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 101~106
DOI : 10.15435/JILASSKR.2015.20.2.101
Gas leakage and dispersion in the underground LNG power plant can lead to serious fire and explosion accident. In this study, computational fluid dynamics simulation was applied to model the dynamic process of gas leakage and dispersion phenomena in a closed space. To analyze the risk assessment factor, such as the flammable volume ratio, transient simulations were carried out for different scenarios. The simulation results visualized the gas distribution with time in the closed space. The flammable volume ratio was introduced for quantitative analysis the fire/explosion probability.
Numerical Study of Fire Behavior Induced by Gas Leakage in Combined Cycle Power Plant
Park, Jaeyong ; Sung, Kunhyuk ; Li, Longnan ; Choi, Jinwook ; Kim, Daejoong ; Lee, Seong Hyuk ; Ryou, Hong Sun ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 107~113
DOI : 10.15435/JILASSKR.2015.20.2.107
To date, the demand for Combined Cycle Power Plant (CCPP) has been continuously increased to overcome the problem of air pollution and lack of energy. In particular, the underground CCPP is exposed to substantial fire and explosion risks induced by gas leakage. The present study conducted numerical simulations to examine the fire behavior and gas leakage characteristics for a restricted region including gas turbine and other components used in a typical CCPP system. The commercial code of FLUENT V.14 was used for simulation. From the results, it was found that flammable limit distribution of leakage gas affects fire behavior. Especially, the flame is propagated in an instant in restricted region with LNG gas. In addition, consequence analysis factors such as critical temperature and radiation heat flux are introduced. These results would be useful in making the safety guidelines for the underground CCPP.
Injection Condition Effects of a Pintle Injector for Liquid Rocket Engines on Atomization Performances
Son, Min ; Yu, Kijeong ; Koo, Jaye ; Kwon, Oh Chae ; Kim, Jeong Soo ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 114~120
DOI : 10.15435/JILASSKR.2015.20.2.114
Effects of injection conditions on a pintle injector which is proper to recent liquid rocket engines requiring low cost, low weight, high efficiency and reusability were studied. The pintle injector with a typical moving pintle was used for atmospheric experiment using water and air. Injection pressures of water were considered 0.5 and 1.0 bar, 0.1 to 1.0 bar for injection pressures of air and 0.2 to 1.0 mm for pintle opening distance. Sauter mean diameters (SMD) of spray was measured at 50 mm distance from a pintle tip and SMD was treated as a representative parameter in this study. As a result, because of shape characteristics of the pintle injector, there was a transient region between the pintle opening distances of 0.6 and 0.7 mm and this region affected to mass flow rates and SMDs. Also, Reynolds numbers for gas, Weber numbers and momentum ratios were adopted as major non-dimensional paramters and the momentum ratio has strong correlation with SMD.
Speed-dependent Emission Characteristics of the Hazardous Air Pollutants from Diesel Medium-duty Trucks according to Emission Standards
Hong, Heekyoung ; Jung, Sungwoon ; Son, Jihwan ; Moon, Taeyoung ; Lee, Sangeun ; Moon, Sunhee ; Yoon, Hyunjin ; Kim, Jeongsoo ; Kim, Jounghwa ;
Journal of ILASS-Korea, volume 20, issue 2, 2015, Pages 121~129
DOI : 10.15435/JILASSKR.2015.20.2.121
This study was designed to investigate the emission characteristics of unregulated pollutants (Aldehyde, VOCs, PAHs) as well as regulated pollutants (CO, HC, NOx and PM) from diesel medium-duty trucks. The emission characteristics of unregulated and regulated pollutants were assessed based on regulation standards (EURO 4 and EURO 5) and intake weight (2.5 ton and 5 ton). The results show that unregulated and regulated pollutants remained almost unchanged at higher speeds but decreased at below 23.5 km/h. Reduction in unregulated and regulated pollutants was noticeable in vehicles of recent regulation standards and light intake weight. The analysis of aldehyde using UPLC showed that formaldehyde and acetaldehyde of aldehyde were most dominant. The GC/MS analysis showed that benzene, toluene, ethylbenzene and xylene of VOCs was over 80% followed by toluene, xylene, ethylbenzene and benzene. In addition, the analysis of PAHs using GC/TOF-MS indicated that bi- and tricyclic aromatic ring of aromatic compounds was 73% and 53% at 2.5 ton and 5 ton vehicles, respectively. The results of this study will be contributed to establish HAPs inventory.