颗粒脱离壁面时湍流诱导的随机振荡现象研究

Particle resuspension from surfaces is ubiquitous and plays a key role in a number of natural and industrial processes. The process of particle detachment from the wall includes particle-wall adhesion, turbulence-particle interaction and other physical mechanisms, and the study of particle resuspension process is of great significance for predicting the resuspension rate of particles and developing the particle removal technology, but so far there is still no unified theory that describes the exact process of particle detachment from the wall. In this paper, high-speed photography experiments are carried out on the re-suspension process of spherical individual particles, and the phenomenon of turbulence-induced random oscillation of particles when they are detached from the wall is observed; the relationship between the frequency of particles’ oscillation and particle size is investigated, and the smaller the size of particles is, the larger the frequency of the oscillation is; the dimensionless number describing the motion of particles.