Investigation on Complex Pressure Fluctuations in a Gas-Solids Circulating Fluidized Bed Rieser

Abstract:

The experiment is carried out in a 13-meter-high circulating fluidized bed(CFB) to investigate gas-solid two-phase flow by pressure sensor. The axial pressure and pressure fluctuation are measured in different solid mass fluxes. With the solid mass flux increasing, pressure gradually increases, and pressure gradually decreases along the riser upwards. The characteristic of pressure fluctuation in the riser is analyzed, which indicates that pressure fluctuation in the riser originates from the inlet. The intensity of the pressure fluctuation decreases along the riser upwards. This pressure fluctuation is composed of two types: one is of low frequency and high amplitude, which is resulted from unstable feeding to the riser and keeps coherent along the axial direction. And the other is of high frequency and low amplitude, which is the result of a variety of factors, such as cluster movement, gas-solid interaction and gas velocity fluctuation.

• Periodical: Advanced Materials Research (Volumes 538-541)
• Pages: 610-615
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.538-541.610
• Online since: June 2012
• Authors: Jun Xu, Xing Xing Chen, Gui Lei Wang, Yao Dong Wei
• Keywords: Pressure Distribution, Pressure Fluctuation, Pressure Transducers, Riser

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