• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.173-178
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• 2003

An experimental study is conducted to investigate the effects of fuel temperature on the spray characteristics of a dual-orifice type swirl injector which is used in gas turbines. The major parameters affecting spray characteristics are fuel temperature and injection pressure entering into the injector. Fuel temperature is shown to have strong influence on the spray characteristics especially at a lower temperature. In this study, fuel temperature is varied from $30^{\circ}C$ to $120^{\circ}C$ and injection pressure is altered from 3 to $7 kg_{f}$ /$cm^{2}$. Two kinds of fuel, which have different surface tension and viscosity, are chosen as an atomizing fluid. As a result, injection instability occurs in the low temperature range due to icing phenomenon and the change of fuel properties. As the injection pressure increases, the kinematic viscosity range for stable atomization becomes wider. The factor controlling the SMD of spray is substantially different depending on the fuel temperature range.

• Journal of Power System Engineering
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• v.12 no.5
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• pp.14-19
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• 2008

In order to meet stringent future emission regulations, especially to reduce Particulate Matter (PM) and NOX, stoichiometric diesel combustion technology with a piezo group-hole nozzle injector is being researched for reduction harmful emissions. A new nozzle layout, namely a group-hole nozzle, which has one group of small orifices with a wide spray included angle was investigated to improve the efficiency of stoichiometric diesel combustion. From this point of view, the group-hole nozzle suggested by Dense Co. is an attractive candidate method applicable to stoichiometric diesel combustion. The group-hole nozzle concept is to reduce the injector nozzle hole diameters without sacrificing spray penetration by closely locating two holes. Experimental studies have proven that the spray from group-hole nozzles have similar spray penetration to that of a single hole with equivalent overall nozzle hole area, but the spray drop sizes (SMD) are reduced, aiding vaporization and mixing.

• Journal of Mechanical Science and Technology
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• v.18 no.7
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• pp.1187-1195
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• 2004

The objective of this study is to investigate the effects of fuel temperature on the spray characteristics of a dual-orifice type swirl injector used in a gas turbine. The major parameters affecting spray characteristics are fuel temperature and injection pressure entering into the injector. In this study, the spray characteristics of a dual-orifice type swirl injector are investigated by varying fuel temperature from - 30$^{\circ}C$ to 120$^{\circ}C$ and injection pressure from 0.29 to 0.69 ㎫. Two kinds of fuel having different surface tension and viscosity are chosen as atomizing fluids. As a result, injection instability occurs in the low fuel temperature range due to icing phenomenon and fuel property change with a decrease of fuel temperature. As the injection pressure increases, the range of kinematic viscosity for stable atomization becomes wider. The properties controlling the SMD of spray is substantially different according to the fuel temperature range.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.2
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• pp.24-29
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• 1998

An experimental study was carried out to investigate the characteristics of spray pattern such as discharge coefficient, spray angle, and mass distribution for two-fluid airblast swirl injector, within the range of fluid supply pressure 0~13kg/$\textrm{cm}^2$. In general atomization is promoted with increasing total gas mass flow and performance of the splay pattern was more stable when radial mass flow was greater than axial mass flow, radial swirler was better than Axial swirler for atomization. Equivalent spray angle did not change with water mass flow except for the condition of 3kg/$\textrm{cm}^2$ and showed the same for the gas mass flow. Mass distribution from the patternator shows that maximum value of the distribution were lowered but distributed larger area when gas flow rate increased. Center of mass position did not change with increasing water mass flow.

• Journal of ILASS-Korea
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• v.28 no.1
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• pp.16-23
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• 2023

The objective of this numerical study is to investigate the effect of the shape and material of the blower blade for the electrified speed sprayer on the blowing performance. The shape of the blade was changed to the bonding angle, the number of blades, the width of the blade, and the blade length based on the existing model. In order to obtain the reliability of the numerical model, the analysis of the grid dependence was performed in the numerical analysis. The numerical analysis results were compared and analyzed in terms of the agricultural chemical penetration length characteristics, flow uniformity characteristics, and velocity distribution characteristics. Furthermore, the effect of material change on weight reduction and structural characteristics was also compared and analyzed. As a result of the analysis, it was found that the optimal condition was that the blade angle was 45°, the number of blades was 12, and the width was 115 mm, which was confirmed through a comparison of the inlet mass flow rate. As a result of the equivalent stress lower than the yield strength due to the material change from aluminum to steel compared to the existing steel, structural defects do not appear, and it is judged that the operation time compared to the battery capacity will be improved through the weight reduction of the blade.