Effect of compressibility on bubbly cavitating flows

来源 :水动力学研究与进展B辑 | 被引量 : 0次 | 上传用户:cx2cx2
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Cavitating bubbly flows can form in separated flows and shear layers leading to local regions high vapor void fraction, and these flows often exhibit periodic shedding of vaporous clouds. Historically, the presence of a liquid re-entrant flow, driven by the kinematics of liquid flow stagnation, has been identified as an important mechanism leading to cavity shedding. However, high local vapor void fractions can also result in a reduced mixture speed of sound and a possible supersonic flow. Our recent findings on different geometries indicate that propagating bubbly shocks in these flows are a primary mechanism of flow instability. In this study, we discuss the effect of compressibility on four geometries, mainly in the generation of propagating bubbly shocks that can influence the cavitation shedding dynamics. In order to elucidate the differences and similarities of the observed cavitation dynamics, and the influence of compressibility, we report observations from a backward facing step, backward facing wedge, NACA0015 hydrofoil, and a bluff body with a wedge cross section.
其他文献
Put forward a new kind of polishing method, ultrasonic magnetic abrasive finishing (UMAF), and studied its mechanism of improving polishing efficiency. By analyzing all kind of forces acting on single abrasive particle in the polishing process and calcula
Investigated the effect of an addition of CaF2 on the crystallization of a glass-ceramic with abrasion resistance. X-ray diffraction, differential thermal analysis and scanning electron microscopy were used to determine the effect. The results showed that
The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner anchor is studied, the mechanical pri
Based on continuum mechanics and rock dynamics, analyzed the micro-structure damage of rock and the impulsive effect under high pressure water jet and developed the dynamic model. Further, on the assumption of that rock was homogeneous and isotropic, a co
A system of on-line contamination detecting in hydraulic oil based on silting principle is accomplished, where, metal filter membrane as detector, solenoid as active force to propel piston to blotter and gain differential pressure, step motor drives the m
By using the Radar penetrating technology and numerical simulations, the fractured zone could be easily determined. Both wall fractured zone and mining action of coal seam roadway were considered, and the bolt reinforcing criteria for wall including low l
It is well known that the formation permeability is not a constant but a function of the in-situ stress environment. This study has been primarily carried out numerically, and to a certain extent, in the field. However, since the rock properties are gener
The structure and principle of the GMM actuator and the new nozzle flapper valve with the GMA were presented. Based on the axis-symmetric FEM model of the GMA,driving magnetic field was computed. And the field distribution for different input currents and
An assistant surface was constructed on the base of boundary that being automatically extracted from the scattered data. The parameters of every data point corresponding to the assistant surface and their applied fields were calculated respectively. In ev
Coal forming environments in the tectonically controlled intermontane Stephanian Cévennes coal basin (Massif central, France) show a complex interelationship between structural and sedimentological features. The study of the general structural features an