Cavitation Analysis with CFD Techniques of the Impeller of a Centrifugal Pump

Abstract

Background/Objectives: The present work evaluates the phenomenon of cavitation in the impeller of a centrifugal pump and observes the behavior of said phenomenon computationally in a simulation as in a physical way in a real pumping system. Methods: The method used is the CFD simulation techniques of ANSYS that allowed designing and analyzing the impeller of the centrifugal pump with convergence criteria of 1000 iterations, an rms value off low lines of 1e-4, a physical scale time of 0.00276 and a conservation value of 1%. In order to analyze the phenomenon of cavitation in the eye of the pumping system impeller, the ball valve V1 was closed an angle of 45°, located in the suction pipe to create an empty pression exceeding the vapor pressure of the pumped fluid. Experimentally recording the pressure reduction at discharge from 42.75 KPa to 19.31 KPa. Findings: The results obtained with the help of the CFD module allowed us to observe the fluid pressure distribution on the pump impeller blades with a value of 2064 Pascals (Saturation Pressure at 18 ° C), indicating the behavior of the fluid, when it passing from a liquid state to a steam state, causing the formation of vapor bubbles whose implosion causes the surface of the impeller to wear out and it is evidenced computationally the areas affected by the presence of the cavitation phenomenon. These surfaces wear out in an area close to the impeller’s eye, and then we observe aware of the material produced by lack of maintenance known as average erosion and finally total impeller damage caused by vapor bubbles. Applications/Improvements: It is suggested for this work to perform an analysis of the other elements that suffer damage due to the erosion of the material of the pump impeller, among them the casing and other elements. Keywords: Cavitation Analysis, Cavitation Phenomenon, Centrifugal Pump, CFD Techniques, Impeller