Dust collector framework airflow is a complex turbulent state composed of tangential, radial and axial directions. Among them, the tangential velocity is the same in the internal and external swirling flow, and outward, and their sizes are different. The tangential velocity decreases with the decrease of the cylinder radius in the internal swirl flow and increases with the decrease of the cylinder radius in the external swirl flow, and reaches the value at the interface between the internal and external swirl flow. The exchange between the sidewall of the dust collector frame and the cyclone of the cone is the main area of ​​secondary dust. The axial speed is downward near the outer wall of the cylinder, upward in the direction near the axis, and the speed at the bottom of the axis, when When the airflow reverses and rises from the bottom of the cone body, the removed dust will be taken away again, forming a back-mixing phenomenon, which affects the dust removal efficiency.

Due to the existence of axial partial velocity and radial partial velocity, the conventional cyclone dust collector often forms an upper ash ring and a lower ash ring during operation. The lower ash ring has a certain effect on the collection and separation of dust particles. The existence of the ring makes the dust that has been trapped and separated on the sidewall of the cylinder first move up along the outer cylinder wall, then move inward along the top cover, and then move down along the outer wall of the inner cylinder, short circuit and discharge from the cyclone, Reduce dust removal efficiency. The existence of radial partial velocity also caused extreme chaos in the flow state of the internal swirling gas flow during the ascent. At this time, the dust particles just make a radial motion (negative sedimentation), they automatically run into the vortex, forming part of the dust particles that are discharged from the cyclone duster by the gas together, and as a result, the efficiency of the cyclone decreases.

The tangential partial velocity of the dust collector framework causes the dust particles to generate a centrifugal sedimentation speed from the inside to the outside under the action of the acceleration in the radial direction, thereby pushing the dust particles to the cylinder wall to be separated. The radial and axial velocities are small, but the directions in the internal and external swirling flow are not consistent. The radial velocity faces outward in the internal swirl flow, and faces inward in the external swirl flow, forming an imaginary cylindrical surface at the interface between the internal and external swirl flow. The radial partial velocity causes the dust particles to be pushed from the outside to the center of the vortex core in the radial direction and is discharged from the cyclone dust collector with the ascending airflow, forming the mainstream of the cyclone separator, so that the gas-solid phase material in the cyclone dust collector is better separated. To overcome the poor separation effect of the separator, we must proceed from three aspects: ① eliminate the “upper ash ring” to avoid the short circuit of dust particles; ② minimize the turbulence of the gas separation section and reduce the chance of secondary dust; ③ overcome the dust particles in The negative settling motion (radial motion) of the separation section.

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