Simulations of the Hydrodynamics in a Novel Spouted Bed Structure with the Swirling Flow Effects
the swirling flow effects
Feng Wu1*, Zhenyu Huang1, Xiaoxun Ma1, Wenjing Zhou2
1,School of Chemical Engineering, Northwest University, Xi' an, China
2,School of Chemical Engineering and Technology, Xiâan Jiaotong University, Xiâan, China
Abstract: The swirling flow technology is adopted in the inlet of the spouted bed so as to strengthen the particles radial mixing between spout and annulus. The gas-solid flow in a cylindrical spouted bed with a swirling flow generator installed on nozzle is numerically investigated by two-fluid model (TFM) with kinetic theory for granular flow. Simulations and analyses have been conducted on two types of spouted beds: conventional spouted bed and spouted bed with integral swirling blade nozzle (ISBN). The simulation results show that: the particle volume fraction near the cone region of spouted bed can be reduced significantly by swirling flow of gas phase cause by the ISBN, and the dead zone at the bottom of the annulus of spouted bed can be eliminated effectively. The value of turbulent kinetic energy of gas phase can be obviously enhanced by swirling flow along the axial direction in spouted bed, especially in the spout region. Also, the value of radial velocity and granular temperature of particle phase in spouted bed can be promoted by swirling flow, which is beneficial to the radial mixing of particles and gas phase between central spout and annulus in spouted bed.
Key words: Spouted bed; Integral swirling blade nozzle; Effect of swirling flow; Enhancement of particle movement; Numerical simulation