关键词: 旋转空化发生器, 内孔结构, 数值模拟, 空化特性, 压力脉动

Abstract: Cavitation is a common phenomenon in industrial production, ship propulsion, aerospace and other fields. In this paper, a highspeed camera is used to observe the flow field in a rotating cavitation generator in a closed cycle test rig, and the numerical simulation is carried out based on the RNG kε turbulence model and the ZwartGerberBelamri cavitation model. The results show that the numerical simulation results are in good agreement with the experimental observation data, which verifies the accuracy and reliability of the numerical simulation method. Due to the centrifugal force, the pressure in the hole increases gradually from the rotor inside to outside. At the bottom of the hole, large vortexes appear and energy are dissipated due to the effect of axial vortex. The fluid at the hole top interacts with the main flow, impacts on the hole top side, and finally forms a weak vortex. Different hole geometries have an important influence on the cavitation effect of the rotating cavitation generator. Under the same condition, the cavitation intensity of the elliptical hole is less than that of the conical hole and cylindrical hole, which indicates that the hole geometry with smooth profile has less local loss and induces the weaker cavitation. For different hole geometries, the dominant frequency of pressure pulsation in rotating cavitation generator is the rotation frequency fi or 24fi (corresponding to the number of hole rows in the circumferential direction), and the maximum pressure pulsation occurs at the inlet pipe side and the outlet pipe side, mainly due to the influence of rotorstator interaction.

Key words: rotating cavitation generator, hole geometry, numerical simulation, cavitation, pressure fluctuation