Oscillating Flow Characteristics Around Coal Particle in High Intensity Sound Field

Abstract

Abstract: To study flow field distribution characteristics around a pulverized coal particle in high intensity acoustic field with sonic frequencies, two-dimensional unsteady mass and momentum conservations for laminar flow in spherical coordinates were developed with actual parameters of power plant boiler. Displacement amplitude of incident sound wave is greater than characteristic length of particles, and acoustic Reynolds number is less than 20. Velocity field, axial pressure gradient, shear stress and flow separation angle around particle were analyzed at different acoustic Reynolds numbers and Strouhal numbers. It is found that axial pressure gradient, shear stress and separation angle are proportional to magnitude of sound at low frequency (~50Hz). However, they are different due to combined effects of curvature and flow acceleration at high frequency (~5 000 Hz). It provides theoretical foundation for further research on acoustic enhancement of heat and mass transfer in power plant boiler.

Key words: high intensity sound, oscillating flow, coal particle, flow separation

CLC Number:

TK224.1

XU Weilong, JIANG Genshan, AN Liansuo, LIU Yuechao, WU Yapan. Oscillating Flow Characteristics Around Coal Particle in High Intensity Sound Field[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2017, 34(4): 425-436.

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