http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정 다이아몬드 형 구멍이 있는 배플을 가진 채널에서의 열전달과 마찰계수
오세경,A.B.K.Putra,안수환 한국동력기계공학회 2008 동력시스템공학회지 Vol.12 No.3
This experimental study investigates the local heat transfer enhancement characteristics and theassociated frictional head in the rectangular channel with a single inclined baffle. Four different types of the baffle are used. The inclined baffles have the width of 19.8 cm, the square diamond of 2.5 cm x 2.5 cm, and the inclination angle of 5o, and number of holes of up to 9. Reynolds number is varied between 23,0 and 57,000. Results show that the heat transfer and friction factor depend significantly on the number of baffle holes and Reynolds number. The friction factor decreases with increasing number and the number of holes on the baffle. It is found that the heat transfer performance of baffle type II(3 hole baffle) has the best values.
수평형 배관에서 고체입자 농도가 마찰계수에 미치는 효과
안수환(S. W. Ahn),아리바시아 크리시나부트라(A. B. K Putra) 한국동력기계공학회 2007 한국동력기계공학회 학술대회 논문집 Vol.- No.-
Generally, the economic concept of optimized design and operating conditions in fluidized bed heat exchangers can hardly be realized. Because the lack of fundamental knowledge about the particle flows, a fluidized bed heat exchanger is rather limited. In the present work, measurements are made on pressure drops and friction factors in the horizontal circular tube with solid particles in the circulating water. Two different solid particles of diameters of 3㎜ and 4㎜ are covered. The Reynolds numbers are ranged from 10,000 to 45,000. It is concluded that the friction factors for the particles of 4㎜ diameter are much higher than those for the particles of 3㎜ diameter. And at the lower particle concentration, the friction factors are strongly influenced by the fluid velocity rather than the particle concentration; However, the effect of the particle concentration on friction factors is also significantly higher at a higher particle concentration operating condition.