Through the comparison of various experimental schemes, the clear conclusions of the trajectories of solid particles in the mine multistage pump impeller are obtained. The statistical data is used to analyze the experimental data to determine the motion parameters of the particles in the inlet of the mine multistage pump impeller. Impeller design and wear studies provide useful experimental evidence. Analysis of test results: Influence of coarse and fine particles on the trajectory of movement For particles with a density greater than water, regardless of the particle size, there is a tendency to move closer to the working face of the blade in the movement from the inlet to the outlet of the impeller, but it is close The speed and position are different.
For fine particles with small mass, the speed of the close is slower, and it is generally concentrated on the blade exit area and the blade collides. As the mass of the particles increases, the speed at which they close together increases, and the position at which the blades collide moves toward the inlet of the blade.
For coarse particles of large mass, most of them collide with the inlet portion of the blade. When the large particles enter the flow path, they leave the working surface, not because of the large mass, but the result of the impact with the blade head. It can be seen from the inlet of the blade that due to the inertial force, the relative movement angle of the coarse particles at the inlet of the blade is smaller than that of the fine particles, and it is easier to approach the blade head and collide with the head. After some of the particles collide with the blade head, they fall to the blade near the field, and the other is: in the flow path of the particle trajectory and wear in the multistage pump impeller of the mine, due to the impact of the particles and the blade impact force, The particles move away from the work surface and no longer collide with the blade exit face.
After a part of the particles collided with the blade head, the advancement was temporarily stopped. During this period of time, the particles and the inlet edge of the blade were rotated around the pump shaft to obtain an additional multi-stage pumping force for the mine, and then fell into the flow near the back of the blade. Road. Due to the small inertia, the fine particles do not concentrate on the blade head movement at the blade inlet, but are constantly biased toward the blade working surface when moving in the flow channel, so that the particle concentration at the blade outlet increases, causing severe wear of the blade.
This is due to the fact that before the particles enter the blade area, they change from axial movement to radial movement, and many particles collide with the inner surface of the rear cover. It can be considered that the collision is elastic and the energy loss is small, so that the speed before and after the collision is almost constant. However, the angle of reflection determines the location of the collision, thereby causing the average value of the inlet velocity of the particles to be substantially constant, while the angle of entry has a certain degree of dispersion. The influence of the impeller speed and the increase of the impeller speed increase the statistical average of the wrap angle of the particle trajectory, and the residence time of the particles becomes shorter. As the rotational speed increases, the inertia of the particles increases, and the particles tend to be more inclined to the blade. Face, thereby increasing its wear.
