CPFD Simulation of Gas-Solid Flow in Dense Phase Zone of Pant-Leg Fluidized Bed with Secondary Air

Document Type : Regular Article

Authors

1 Engineering Research Centre of Oil Shale Comprehensive Utilization, Ministry of Education, School of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, Jilin Province, China

2 Department of Chemical & Biological Engineering, University of British Columbia, Vancouver, V6T1Z3, Canada

10.47176/jafm.15.05.1130

Abstract

Aggregation of fluidization media may appear at the dense phase region of the pant-leg fluidized bed near the incline walls. When the particles flow along the inclined wall, the friction and drag force will cause the particles to accumulate on the inclined wall, resulting in an uneven distribution of particles. The stagnant zones can be minimized by correctly arranging secondary air. Computational particle fluid dynamics (CPFD) method was used to simulate the gas-solid two-phase flow pattern in the dense phase region of pant-leg fluidized bed. Cold tests were performed on a benchtop pant-leg fluidized bed. A high speed imaging technology was used to monitor the flow pattern in the dense phase area, whereas the bubble size and residence time were compared to verify the accuracy of the simulation. The gas-solid flow patterns under various models were simulated. The influence of different secondary air velocities on the reduction of stagnant zone in the dense phase zone of the fluidized bed were predicted. The results indicated that the introduction of secondary air could effectively promote the mixing of particles, and weaken the accumulation of particles on the inclined wall surface. Moreover, secondary air can effectively promote the flow between the gas-solid two-phases and improve the combustion characteristics in the furnace.

Keywords


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Volume 15, Issue 5
September and October 2022
Pages 1319-1331
  • Received: 13 February 2022
  • Revised: 12 May 2022
  • Accepted: 16 May 2022
  • First Publish Date: 26 June 2022