Numerical simulation of cavitation washer in pipe cleaning

Cavitation water jet can take advantage of the power generated from vacuole rupture to enhance the performance of the jet. Studies have shown that the pressure of the cavitation jet is 8.6-124 times as high as continuous pressure in the same pump conditions, therefore the cavitation jet is widely utilized in cutting, cleaning and descaling. The study focused on blade-type cavitation washer, using three-dimensional periodic modeling, combined with structured and unstructured grids, analyzed the two-phase Singhal cavitation model in a finite volume CFD way. By taking turbulence intensity and non-condensable gas into account, the cleaning mechanism was analyzed and flow characteristics were gain. The results show that the cavitation effect mainly produced in two zones, the blade tip area around the pipe wall and the double-blade staggered narrow gap. Throttling effect is the main cause of the cavitation effect. The cavitation number is used to evaluate the strength of the cavitation, and the cavitation number is between 0 and 0.5.