CAJ | 학술논문

针对磁流化床可实现磁稳流化的特点,提出了一种确定和计算磁稳流化区域的方法.通过对4种不同粒径的铁磁颗粒(其平均粒径范围231～512 μm)进行流态化实验研究,得到铁磁颗粒分别在磁场强度为0～7 330 A/m时的流化曲线.实验中采用压降波动的方法测定最小鼓泡流化速度,进而确定磁稳流化区域的范围.基于铁磁颗粒的流化曲线,分析得到铁磁颗粒的流化特性,讨论了颗粒粒径、磁场强度对磁稳流化区域的影响;运用多元回归的方法得到磁稳流化区域与磁重势能比、阿基米德数以及雷诺数之间的实验关联式.与已有的研究相比,此式较为简单,具有较好的适用性,据此式可以方便地给出磁流化床磁稳流化状态运行时的合理参数.
침대자류화상가실현자은류화적특점,제출료일충학정화계산자은류화구역적방법.통과대4충불동립경적철자과립(기평균립경범위231～512 μm)진행류태화실험연구,득도철자과립분별재자장강도위0～7 330 A/m시적류화곡선.실험중채용압강파동적방법측정최소고포류화속도,진이학정자은류화구역적범위.기우철자과립적류화곡선,분석득도철자과립적류화특성,토론료과립립경、자장강도대자은류화구역적영향;운용다원회귀적방법득도자은류화구역여자중세능비、아기미덕수이급뢰낙수지간적실험관련식.여이유적연구상비,차식교위간단,구유교호적괄용성,거차식가이방편지급출자류화상자은류화상태운행시적합리삼수.
To determine and calculate the stable fluidization zone in a magnetically fluidized bed, the fluidization characteristics of magnetic particles are investigated. Four kinds of magnetic particles with different average diameters, ranging from 231 to 512 μm, are fluidized in the presence of magnetic fields with specified values of the intensity in the range of zero to 7 330 A/m, and the particle fluidization curves arc plotted. For marking the stable fluidization zone in the curves, the minimum bubbling velocities of particles are measured by the pressure-drop fluctuation. Based on the fluidization curves, the influences of the average particle diameter and magnetic field intensity on the zone are analyzed and discussed. A correlation to determine the stable fluidization zone is derived from the experimental data, using three dimensionless numbers, i. e., the ratio of magnetic potential to gravity potential, the Reynolds number and the Archimedes number. Compared with available data reported, it is shown that the correlation is more simplified to predict relative parameters for the bed operating in the state of stable fluidization under reasonable conditions.