The hydraulic cavitation affected by nanoparticles in nanofluids

Abstract

When liquids flow through a throttling element, the velocity increases and the pressure decreases. At this point, if the pressure is below the saturated vapor pressure of this liquid, the liquid will vaporize into small bubbles, causing hydraulic cavitation. In fact, a vaporization nucleus is another crucial condition for vaporizing, and particles contained in the liquid can also work as the vaporization nuclear. As a novel heat transfer medium, nanofluids have attracted the attention of many scholars. The nanoparticles contained in the nanofluids play a significant role in the vaporization of liquids. In this paper, the effects of the nanoparticles on hydraulic cavitation are investigated. Firstly, a geometric model of a perforated plate, the throttling element in this paper, is established. Then with different nanoparticle volume fractions and diameters, the nanofluids flowing through the perforated plate are numerically simulated based on a validated numerical method. The operation conditions, such as the ratio of inlet to outlet pressures and the temperature are the considered variables. Additionally, cavitation numbers under different operating conditions are achieved to investigate the effects of nanoparticles on hydraulic cavitation. Meanwhile, the contours are extracted to research the distribution of bubbles for further investigation. This study is of interest for researchers working on hydraulic cavitation or nanofluids.