کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
237987 | 465735 | 2010 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Simulations of flow behavior of gas and particles in spouted bed with a porous draft tube Simulations of flow behavior of gas and particles in spouted bed with a porous draft tube](/preview/png/237987.png)
Flow behaviors of particles in a two-dimensional spouted bed with a porous draft plates are studied using a fluid dynamic computation with kinetic–frictional stresses models. Gas flow through the porous draft tube is simulated by Brinkman–Darcy–Forchheimer formulation. The distributions of concentration and velocities of particles are predicted. Simulated results predict the solid circulation rate and gas flux rate measured in the spouted bed with a porous draft tube (Ishikura et al., 2003). The solid circulation rate in the spouted bed with a porous draft tube is larger than that with a non-porous draft tube. The predicted bed pressure drop with the porous draft tube is high in comparison to the spouted bed with non-porous draft tube. The effect of the porosity of the porous draft tube on distributions of gas flux rate through the annulus and solid circulation rate are discussed.
Simulations show that the spouted bed with a porous draft tube consists mainly of four zones. The spout with low concentration and high gas velocity locates within the porous draft tube. The annulus with high concentration and low velocity of particles sliding downward is between the porous draft tube and walls. Near the top of the spout, a fountain surrounding the spout axis is formed. Near the entrance region the entrainment is existed where particles are transported from the annulus to the spout. Particles from the spout move downwards in the fountain, and then back to the spout through the entrainment. The circulation of particles is formed in the spouted bed.Figure optionsDownload as PowerPoint slide
Journal: Powder Technology - Volume 199, Issue 3, 15 May 2010, Pages 238–247