• Journal of Mechanical Science and Technology
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• v.20 no.12
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• pp.2242-2249
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• 2006

The rolling piston type rotary compressor has been widely used for refrigeration and air-conditioning systems due to its compactness and high-speed operation. The present analysis is part of a research program directed toward maximizing the advantages of refrigerant compressors. The study of lubrication characteristics in the critical sliding component is essential for the design of refrigerant compressors. Therefore, theoretical investigation of the lubrication characteristics of a rotary compressor being used for refrigeration and air-conditioning systems was investigated. The Newton-Raphson method was used for a partial elastohydrodynamic lubrication analysis between the vane and the rolling piston of a rotary compressor. The results demonstrated that the vane thickness and the center line position of the vane significantly influenced the friction force and the energy loss between the vane and the rolling piston.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.1
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• pp.27-38
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• 2014

Flow mixing and pressure drop characteristics for marine selective catalytic reduction applications were investigated numerically to develop an efficient static mixer. Two different mixers, line- and swirl-type, were considered. The effect of vane angles on the relative intensity, uniformity index, and pressure drop was investigated in a swirl-type mixer; these parameters are dramatically affected by the mixer geometry. The presence of a mixer, regardless of the mixer type, led to an improvement of approximately 20% in the mixing performance behind the mixer in comparison to not having a mixer. In particular, there was a tradeoff relationship between the uniformity and the pressure drop. Considering the mixing performance and the pressure drop, the swirl-type mixer was more suitable than the line-type mixer in this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5384-5391
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• 2011

The computational fluid dynamics was analyzed for the pressure distribution, stream velocity distribution, stream line field, retention time and temperature distribution which are applied to the catalyst layer in the RCO reactor to derive the optimum operating condition of the heat condensing type catalytic oxidation (RCO) reactor. The results from the computational analysis revealed that the pressure loss due to the ceramic honeycomb in the catalytic bed of the reactor which is operating currently is not significant and the stream velocity (1.8~2.7 m/s) after the ceramic filter is working in stability without big channeling. To improve the stream velocity distribution of the air stream, it is necessary to extension of the connecting range between the plenum and catalytic bed inside the facility. However, the method of attaching the air stream guide vane or the perforated plate inside the reactor was not so effective.