Numerical Simulation of a Cavitating Pulsating Water Jet Used for Removing Contaminants from Metal Surfaces

Abstract

The paper presents an environmentally friendly method for cleaning metal surfaces from contaminants. In this method, the contaminants are removed from surfaces by a cavitating pulsating water jet generated in the nozzle and directed at the surface. The cavitation-generating effectiveness of three various design nozzles was investigated numerically using the SolidWorks 2015 Flow Simulation software. The volume fraction of the vapour generated in the flow inside the nozzles was determined. Selected nozzle was studied experimentally in respect of efficiency of abrasive particle removal. After having carried out experiments to test the removal efficiency of the method, it was established that the water that has remained on the cleaned surface decreases its effectiveness. To solve this problem, a prototype of a cavitation-generating head with a water removal system was created and studied numerically.

Study of the efficiency of cavitation generating head with water removal system used to remove foulants from metal surface

“…Single cavitation generating nozzle directed to the surface being cleaned would also be suitable for surface cleaning, but previous research [20] showed that traces of water remain on the cleaned surface, which reduce the efficiency of the proposed method. Therefore, there was a need to design a system (head) with water removal system.…”

“…Head consists of three cavitation generating nozzles (atomizers) NECBD [15,20,21] arranged at 120°angle with respect to each other (Figs. 2 and 3, view I).…”

“…Nozzles whose angular position in relation to the axis of the head can be changed, generate cavitation and direct the flows on the surface being cleaned. The results of numerical investigations of cavitation generating efficiency of nozzles are presented in [20,21]. Water removal system works similarly as conventional cyclone separator.…”

Performance Optimization of Underwater Crushing Unit Based on AHP

“…Hua et al [12] developed a new hydroblasting cleanup system that can be loaded onto underwater cleaning robots and can effectively interrupt the growth of marine biofouling. Ralys et al [13] designed a cavitation-generating head with a water removal system and built the prototype, avoiding the possibility that water left on the cleaned surface would decrease the effectiveness of the cavitation jet. It was preliminarily demonstrated that the method of ultrasonic-enhanced submerged cavitation jets for cleaning marine biofouling is practical by Zhong et al [14] when they suggested a new ultrasonic-enhanced submerged cavitation jet ship fouling cleaning technique.…”