http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
윤정환(Joung-Hwan Youn),임태훈(Tae-Hun Lim),박근욱(Keun-Uk Park),정낙규(Nak-Kyu Chung),김진흥(Jin-Heung Kim),오율권(Yool-Kwon Oh) 대한기계학회 2001 대한기계학회 춘추학술대회 Vol.2001 No.9
This study presents experimental work on phase change heat transfer, in order to increase heat transfer rate, ultrasonic vibrations were introduced. Solid-liquid phase change occurs in a number of situations of practical interest. This study reveal that ultrasonic vibrations accompany the effects like agitation, acoustic streaming, cavitation, and oscillating fluid motion. Such effects are a prime mechanism in the overall melting process when ultrasonic vibrations are applied. Some common examples include the melting of edible oil, metallurgical process such as casting and welding, and materials science applications such as crystal growth. Therefore, this study presented the effective way to enhance phase change heat transfer.
박설현,윤정환,서동표,정대훈,오율권 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1
Polymer drag reduction can offer a attractive way to utilize ready-made facilities in crude-oil transport system without additional large expenditure. Also, drag reduction in two phase flow can be applied to phase change system such as chemical reactor, pool and pump impeller which occurs cavitation. But the research on drag reduction in two phase flow has not been investigated. Therefore, experimental investigations have been carried out to analyze the drag reduction in the single phase and two phase flow. The objectives of the proposed investigation are primarily to identify and develop high performance polymer additives for fluid transportation. And drag reduction will be evaluated in horizontal flow by measuring void fraction, pressure drop, mean liquid velocity and turbulent intensity