Experimental study on the effect of dissolved CO2 on cavitation erosion intensity by submerged waterjet

Abstract

Gas content has an important influence on the intensity of cavitation erosion, affecting the formation and collapse of cavitation nuclei. Previous studies have primarily focused on the influence of dissolved oxygen and nitrogen on cavitation erosion. Studying the effect of other gases on cavitation erosion can promote a better understanding of cavitation. This study first analysed the erosion morphology with various standoff distances under the same cavitation number. Subsequently, a typical erosion profile at a set distance was selected to study the effect of dissolved CO2 on submerged self-resonating waterjet cavitation erosion. The mass loss, maximum erosion height difference, and average roughness were used as indicators of cavitation erosion intensity. These three indicators show a similar trend with the change in cavitation erosion intensity. When the CO2 content was small, the dissolved CO2 primarily affected the cavitation intensity by affecting the pH of the water. With a further increase in air content, the inhibitory effect of gas content on the cavitation erosion intensity became apparent.