• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E
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• pp.59-68
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• 2000

In this paper Various aerosol cyclones that are developed recently form Kwangju Institute of Science and Technology(KJIST) for increasing collection efficiency or for decreasing pressure drop are reviewed. For the first time, new sets of experimental data are reported on the particle collection efficiency of cyclones with modified surface bodies namely, spiral guide body, circumferential groove body, and vertical groove body. Multi-cylinder cyclones by adding one or two additional cylindrical walls into the conventional cyclone are also described. Ad an attempt to increase the collection efficiency of small particles, electrocyclone using an externally applied electric field was designed and operated. In addition, factors affecting the cyclone performance were studied including flowrate, body and outlet sizes, cyclone dust outlet, and gas property.

• Atmosphere
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• v.16 no.4
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• pp.319-332
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• 2006

This study examines the capability of the WRF (Weather Research and Forecasting) model in reproducing heavy rainfall that developed over the Korean peninsula on 26-27 June 2005. The model is configured with a triple nesting with the highest horizontal resolution at a 3-km grid, centered at Yang-dong, Gyeonggi-province, which recorded the rainfall amount of 376 mm. In addition to the control experiment employing realistic orography over Korea, two consequent sensitivity experiments with 1) no orography, and 2) no land over Korea were designed to investigate orographic effects on the development of heavy rainfall. The model was integrated for 48 hr, starting at 1200 UTC 25 June 2005. The overall features of the large-scale patterns including a cyclone associated with the heavy rainfall are reasonably reproduced by the control run. The spatial distribution of the simulated rainfall over Korea agreed fairly well with the observed. The amount of predicted maximum rainfall at the 3-km grid is 377 mm, which located about 50 km southeast from the observed point, Yang-Dong, indicating that the WRF model is capable of predicting heavy rainfall over Korea at the cloud resolving resolutions. Further, it was found that the complex orography over the Korean peninsula plays a role in enhancing the rainfall intensity by about 10%. The land-sea contrast over the peninsula was fund to be responsible for additional 10% increase of rainfall amount.