Development of a Particle Bed Heat Exchanger(I) -An Experimental Study on Heat Transfer Characteristics of Fluidized Bed Heat Exchanger with Double Pipe (Counterflow)

입자층(粒子層)을 이용(利用)한 열교환기(熱交換器) 개발(開發)에 관(關)한 연구(硏究)(I) - 유동층형(流動層形) 이중관식(二重管式) 열교환기(熱交換器)의 전열특성(傳熱特性)에 대한 실험적(實驗的) 연구(硏究) (대향류식(對向流式))

In this study, the overall heat transfer coefficients are calculated on fluidized bed double pipe heat exchanger and single phase double pipe heat exchanger at the same condition. The effect of the particle size, its material, fluidizing velocity and static bed height on overall heat transfer coefficient has been investigated. The main conclusions obtained from the experiment are as follows. 1. The overall heat transfer coefficient of the fluidized bed heat exchanger is higher than that of single phase forced convective heat exchanger (maximum 2.3 times) 2. The value of the overall heat transfer coefficient increase with an increase in static bed height and decrease with an increase in particle size. 3. For the same particle size, the particle of low density can obtain higher overall heat transfer coefficient than that of high density.