• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.28-35
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• 2012

This study is on SCR reactor, NOx reduction system in Marine that has been an issue nowadays. Especially design data was obtained by numerical on flow uniformity that is one of the design factor in SCR reactor. Also pressure drop on catalyst size inserted into SCR reactor was compared by experiment and numerical analysis. S/W, numerical analysis used for this study was confirmed that the result of numerical analysis used STAR-CCM+, common use CFD code, pressure drop on catalyst is not big different from the result of numerical analysis. In addition, degree of uniformity of liquid on SCR reactor was over 0.9. Whereas it was assured that degree of uniformity of liquid was changed depends on the shape of pipe at the entrance of SCR.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.89.1-89.1
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• 2005

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.91-95
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• 2000

The effects of argon gas flow on the axial temperature gradient near the interface, the oxygen concentration, and the radial oxygen uniformity was investigated for 8-inch CZ silicon growth. As argon flow rate was increased, the temperature gradient was increased in the crystal near the crystavmelt interface and the oxygen content in the crystal was decreased. But the radial oxygen uniformity was deteriorated. It was found that argon flow is one of the important growing parameters to affect the quality of crystals such as oxygen content and uniformity.

• 한국가시화정보학회:학술대회논문집
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• 2004.11a
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• pp.48-51
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• 2004

Chemical Mechanical Polishing(CMP) is popularly used in production of semiconductor because of large area polishing ability probability of improvement for more integrated circuit. However, present CMP processing causes some non-uniformity errors which can be critical for highly integrated circuit. Previous studies predict that flow-field of slurry during CMP can create non-uniformity, but no quantitative measurement has conducted. In this study, using PIV, slurry velocity flow-field during CMP is measured by changing the ratio of RPM of pad and carrier with tuned PIV system adequate for small room in CMP machine and Cabot's non-groove pad Epad-A100. The result show that velocity of slurry is majorly determined by pad-rpm and the ratio of between carrier and pad rpm make some changes in streamlines.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.3
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• pp.46-55
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• 2000

Four types of different flow inlet models were tested to improve the flow uniformity at the inlet of the radiator and to prevent thermal damages of auxiliary units from the hot air in the bus engine room. Measurements and numerical calculations were performed and their results were in a good agreement with each other. Simultaneously temperature measurements were carried out under the conditions of actual bus driving. As designing the new flow inlet at the partition board which seperates the engine space and radiator space, flow circulation can be achieved and fresh air comes into the engine room from the bottom. It was proved that new inlet makes the one air temperature cooling down in the engine room, the other uniformity improvement.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.10
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• pp.667-673
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• 2017

We investigated the temperature uniformity in an anode-supported solid oxide fuel cell, using the open source computational fluid dynamics (CFD) toolbox, OpenFOAM. Numerical simulation was performed in three different flow paths, i.e., co-flow, counter-flow, and cross-flow paths. Gas flow in a porous electrode was calculated using effective diffusivity while considering the effect of interconnect rib. A lumped internal resistance model derived from a semi-empirical correlation was implemented for the calculation of electrochemical reaction. The result showed that the counter-flow path displayed the most uniform temperature distribution.

• Journal of Environmental Science International
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• v.22 no.11
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• pp.1481-1498
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• 2013

The SCR (selective catalytic reduction) system is highly-effective technique for NOx reduction from exhaust gases. In this study, the effects of the direction and size of nozzle and the ammonia injection concentration on the performance of SCR system are analyzed by using the computational fluid dynamics method. When the nozzle is arranged in zigzaged direction which is normal to exhausted gas flow, it is shown that the uniformity of gas flow and the NH3/NO molar ratio is improved remarkably. With the change of the ammonia injection concentration from 0.2 vol%(wet) to 1.0 vol%(wet), the uniformity of gas flow shows a good results. As the size of nozzle diameter changes from 6 mm to 12 mm, the uniformity of gas flow is maintained well. It is shown that the uniformity of the $NH_3/NO$ molar ratio becomes better with decreasing the ammonia injection concentration and the size of nozzle diameter.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.3
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• pp.16-23
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• 2008

Flow analyses have been performed to investigate the uniformity of propellant flow through the oxidizer manifold of a 30 tonf full-scaled combustor. Injectors were simulated as porous medium layers of equivalent pressure drops. The uniformity of oxidizer propellant has been analyzed for various diameters of holes in vertical/horizontal distributors and configurations of oxidizer inlet to propose an improved design solution. It has been proven that the mass flow uniformity were improved by adjusting the holes in vertical/horizontal distributors.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.4
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• pp.108-114
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• 2007

This research represents the catalytic converter for application in the motorcycle. We have to consider about catalytic converter for reducing exhaust gas strength regarding the displacement volume enlargement. The catalytic converter has been widely used to satisfy the regulations of pollutant emissions from automobiles. Recently, all catalytic converter researches are about automobile. Study about motorcycle catalytic converter has not been conducted yet. In this study, flow uniformity and pressure distribution were simulated in the monolithic inlet of catalytic converter for motorcycle. Exhaust pulsation pressure was set as transient condition about. It was found that flow uniformity shown in base model (0.85) was lower than megaphone model (0.98).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.7
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• pp.709-716
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• 2013

A fan filter unit (FFU) is a device which supplies clean air from the ceiling in a clean room. With an increase in its size, velocity variation occurs within the exhaust plane and this damage the product quality or productivity. Hence, a guide vane is installed inside the device to enhance the velocity uniformity. Because the vane reduces the flow rate for a given pumping power, an optimum design is required to achieve velocity uniformity while minimizing the flow rate reduction at the same time. To find a geometry that satisfies these requirements, a series of numerical simulations has been conducted while changing the angle and length of the guide vanes. By changing the geometry of the side guide vane, the velocity uniformity increased by 3.7% and the flow rate decreased by 1.5%. For the center guide vane, the velocity uniformity increased by 2.9% and the flow rate decreased by 0.7%.