摘要
以空泡动力学分析为基础,考虑自振射流流场压力变化特性、空泡传热和传质规律,建立了空化气泡在自振射流流场中动态变化的计算模型,研究了空泡溃灭强度的影响因素。研究表明,空化射流破坏岩石的能力主要取决于空泡第1次溃灭的强度,空泡后续溃灭的强度显著降低。自振效应使空泡溃灭压力峰值及其持续时间增大,能大幅提高空泡溃灭强度。水力参数是空泡溃灭强度的主要影响因素:一定射流速度下,存在最优的围压值,使空泡溃灭强度达到最大;增大射流速度能提高空泡溃灭强度。流体物性对空泡溃灭强度的影响较小:溃灭强度随流体密度增大而降低,受流体黏度和表面张力的影响较小。研究结果有助于了解空化效应提高射流冲蚀性能的作用机理,提升自振空化射流技术的现场应用效果。
Based on bubble dynamics theory,a mathematic model describing the cavitation bubble size variation in the flow field of self-resonating cavitating jet was developed considering the pressure field and mass and heat exchange between cavitation bubble and ambient fluid.With this model,the influence factors on the cavitation intensity are investigated.The results show that the destructiveness of cavitating jet in breaking rocks depends on the bubble's first collapse,with decreasing intensity in the subsequent collapses.The self-resonating effect significantly enhances the cavitation intensity by promoting the collapse pressure and elongating its duration.Hydraulic parameters are proven to be the dominating factors influencing cavitation intensity:while collapse intensity monotonously increases with jet velocity,there exists an optimum ambient pressure where highest collapse intensity can be achieved.Conversely,thefluid properties show minor influences:cavitation intensity only slightly decreases with the increasing of fluid's density and barely changes with the variation of viscosity and surface tension.The results from this investigation help to uncover the mechanism of the enhanced erosion potential of self-resonating cavitating jet.The conclusions can be used to further improve the performance of self-resonating cavitating jet in field applications.
作者
彭可文
田守嶒
李根生
黄中伟
杨睿月
郭肇权
PENG Kewen;TIAN Shouceng;LI Gensheng;HUANG Zhongwei;YANG Ruiyue;GUO Zhaoquan(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2018年第2期326-332,共7页
Petroleum Exploration and Development
基金
国家自然科学基金(51674275
U1562212
51521063)
关键词
自振空化射流
空化气泡
溃灭强度
水力参数
流体物性
self-resonating cavitating jet
cavitating bubble
collapse intensity
hydraulic parameters
fluid properties
