Numerical Investigation for Mitigation of Cavitation in High-Speed Marine Propeller Using Mass Injection Approach

Cavitation is a prevailing phenomenon for submerged high-speed bodies. Among the various mitigation methods, mass injection method is an intriguing approach. The focus of the study is to numerically evaluate the important mechanical properties for the method to be effective and economic for the industry. In this study, the sheet cavitation has been considered to evaluate the mentioned factors. For this novel purpose, the combination of k – ω SST turbulence model with the curvature correction and Zwart cavitation model has been found robust enough to encompass the complexities of the numeral system, which has been applied on a modified INSEAN E779A propeller. The theoretical calculation and simulated result showed that the compressibility of the injected fluid is a demanding mechanical property, as in high RPM the incompressible fluid contributes to cavitation by forming bubbles of vapour through phase changing phenomenon. The effectiveness of air injection is prominent, as the maximum cavitation number of 2.61 has been decreased to 1.82 and 1.88 in case of air injection of 50 m/s and air injection of 100 m/s, respectively. It has also been found that the orientation of the flow of injection plays a decisive role in the performance of mitigation of cavitation. Furthermore, according to calculation compressible fluid is significantly energy efficient than incompressible fluid for injection. Moreover, it has been found that the diffusion of the injected body is not solely depend on pressure fluctuation. However, the velocity and the orientation of the injection directly influence the diffusion and subsequently the mitigation. Thus, it has been proposed that the injection control system has to be dynamic and responsive rather than static.