| Title |
Analysis of Particles Motion in Vertical Rayleigh Flow |
| Authors |
고석보(Seok-Bo Ko) ; 전용두(Yong-Du Jun) ; 이금배(Kum-Bae Lee) |
| Keywords |
입자 거동 ; 유동층 ; 열교환기 ; 레일리 유동 ; 상승관 Particle motion ; Fluidized bed ; Heat Exchanger ; Rayleigh flow ; Riser |
| Abstract |
Suspended particles behavior when they go through a vertical riser with heat transfer is of significant concern to system designers and operators in pneumatic transport, various processes such as in chemical, pharmaceutical and food industries. When it comes with the energy system, that knowledge is critical to the reliable design practices of related equipment as heat exchangers, especially in the phase of system scale-up. Without having a good understanding of the related physics, many scale-up practices based on their pilot plant experience suffer from unexpected behaviors and problems of unstable fluidization typically associated with excessive pressure drop, pressure fluctuation and even unsuccessful particle circulation. In the present study, we try to explain the observed phenomena with related physics, which may help understanding of our unanswered experiences and to provide the designers with more reliable resources for their work. We selected hot exhaust gas with solid particle that goes through a heat exchanger riser as our model to be considered. The effect of temperature change on the gas velocity, thermodynamic properties, and eventually on the particles motion behavior is reviewed along with some heat transfer analyses. The present study presents an optimal riser length at full scale under given conditions, and also defines the theoretical limiting length of the riser. The field data from the numerical analysis was validated against our experimental results. |