Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds
In our previous paper, particle and temperature segregations in a fluidized bed of binary particle mixtures were experimentally examined, and heat transfer in the segregated fluidized bed was investigated. As the results, it was shown that the temperature segregation results mainly from low heat tra...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Japan Society of Mechanical Engineers
2007-04-01
|
| Series: | Journal of Thermal Science and Technology |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/jtst/2/1/2_1_55/_pdf/-char/en |
| _version_ | 1818320234203840512 |
|---|---|
| author | Yihua GU Isao SATOH Takushi SAITO Tatsuya KAWAGUCHI |
| author_facet | Yihua GU Isao SATOH Takushi SAITO Tatsuya KAWAGUCHI |
| author_sort | Yihua GU |
| collection | DOAJ |
| description | In our previous paper, particle and temperature segregations in a fluidized bed of binary particle mixtures were experimentally examined, and heat transfer in the segregated fluidized bed was investigated. As the results, it was shown that the temperature segregation results mainly from low heat transfer coefficient through the interface layer, which exists between the flotsam-rich and jetsam-rich layers, and that the heat transfer coefficient increases rapidly with increasing the excess gas velocity. Following our previous paper, particle motion in the segregated fluidized bed was experimentally investigated in this paper, in order to make quantitative discussion on the relation between the heat transfer coefficient and particle motion in the interface layer. In the experiment, the Particle Imaging Velocimetry (PIV) method was applied to study the concentration and motion of particles in the segregated fluidized bed. A modified solid circulation model was built up to model the particle motion in the segregated fluidized bed. The experiment results showed that the vertical particle exchange rate of the interface layer increases with the excess gas velocity, and that the vertical heat transfer coefficient through the interface layer is mainly determined by the average particle exchange rate in the interface layer. Variations of the apparent thermal conductivity at different height in the particle layers were also determined by the vertical variation of the particle exchange rate. It was shown that the heat transfer coefficient or the thermal conductivity in the interface layer is influenced by the densities and specific heat capacities of the particles. |
| first_indexed | 2024-12-13T10:21:46Z |
| format | Article |
| id | doaj.art-0fad6d98e8e04089921f617889ff9829 |
| institution | Directory Open Access Journal |
| issn | 1880-5566 |
| language | English |
| last_indexed | 2024-12-13T10:21:46Z |
| publishDate | 2007-04-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Journal of Thermal Science and Technology |
| spelling | doaj.art-0fad6d98e8e04089921f617889ff98292022-12-21T23:51:10ZengThe Japan Society of Mechanical EngineersJournal of Thermal Science and Technology1880-55662007-04-0121556610.1299/jtst.2.55jtstHeat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized BedsYihua GU0Isao SATOH1Takushi SAITO2Tatsuya KAWAGUCHI3Dept. of Mechanical and Control Engineering, Tokyo Institute of TechnologyDept. of Mechanical and Control Engineering, Tokyo Institute of TechnologyDept. of Mechanical and Control Engineering, Tokyo Institute of TechnologyDept. of Mechanical and Control Engineering, Tokyo Institute of TechnologyIn our previous paper, particle and temperature segregations in a fluidized bed of binary particle mixtures were experimentally examined, and heat transfer in the segregated fluidized bed was investigated. As the results, it was shown that the temperature segregation results mainly from low heat transfer coefficient through the interface layer, which exists between the flotsam-rich and jetsam-rich layers, and that the heat transfer coefficient increases rapidly with increasing the excess gas velocity. Following our previous paper, particle motion in the segregated fluidized bed was experimentally investigated in this paper, in order to make quantitative discussion on the relation between the heat transfer coefficient and particle motion in the interface layer. In the experiment, the Particle Imaging Velocimetry (PIV) method was applied to study the concentration and motion of particles in the segregated fluidized bed. A modified solid circulation model was built up to model the particle motion in the segregated fluidized bed. The experiment results showed that the vertical particle exchange rate of the interface layer increases with the excess gas velocity, and that the vertical heat transfer coefficient through the interface layer is mainly determined by the average particle exchange rate in the interface layer. Variations of the apparent thermal conductivity at different height in the particle layers were also determined by the vertical variation of the particle exchange rate. It was shown that the heat transfer coefficient or the thermal conductivity in the interface layer is influenced by the densities and specific heat capacities of the particles.https://www.jstage.jst.go.jp/article/jtst/2/1/2_1_55/_pdf/-char/enmulti-component fluidized bedparticle segregationtemperature segregationparticle motionpivadvection heat transferapparent thermal conductivity |
| spellingShingle | Yihua GU Isao SATOH Takushi SAITO Tatsuya KAWAGUCHI Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds Journal of Thermal Science and Technology multi-component fluidized bed particle segregation temperature segregation particle motion piv advection heat transfer apparent thermal conductivity |
| title | Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds |
| title_full | Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds |
| title_fullStr | Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds |
| title_full_unstemmed | Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds |
| title_short | Heat Transfer in Segregated Fluidized Beds Part 2: Particle Motion and Its Effects on the Heat transfer in the Segregated Fluidized Beds |
| title_sort | heat transfer in segregated fluidized beds part 2 particle motion and its effects on the heat transfer in the segregated fluidized beds |
| topic | multi-component fluidized bed particle segregation temperature segregation particle motion piv advection heat transfer apparent thermal conductivity |
| url | https://www.jstage.jst.go.jp/article/jtst/2/1/2_1_55/_pdf/-char/en |
| work_keys_str_mv | AT yihuagu heattransferinsegregatedfluidizedbedspart2particlemotionanditseffectsontheheattransferinthesegregatedfluidizedbeds AT isaosatoh heattransferinsegregatedfluidizedbedspart2particlemotionanditseffectsontheheattransferinthesegregatedfluidizedbeds AT takushisaito heattransferinsegregatedfluidizedbedspart2particlemotionanditseffectsontheheattransferinthesegregatedfluidizedbeds AT tatsuyakawaguchi heattransferinsegregatedfluidizedbedspart2particlemotionanditseffectsontheheattransferinthesegregatedfluidizedbeds |