摘要
针对可压缩空化流流场细节特征,对空化的回射流机制与凝结激波机制下的空化云演化过程进行大涡模拟。通过对比文献实验数据验证了可压缩空化流数值模拟方法的可靠性,并分析了空化数σ、CN空化数、St数和压力损失系数K等无量纲参数,发现数值模拟对空化流压力-速度耦合计算的准确性方面还有待进一步提升。两种空化机制情况下,涡环生长是空化云脱落后耗散过程,涡环溃灭成游离涡是耗散结果;通过大涡模拟实现两种机制下的空化模拟,对比发现回射流机制的空化的无量纲参数偏差较少,凝结激波具有一定偏差;凝结激波的功率谱密度分析发现满足-7/3标度律,回射流满足-5/3标度律。
Large-Eddy Simulation was conducted to study the evolution process of cavitation clouds under the mechanisms of cavitation shedding and condensation shock wave.The simulation was focused on the detailed features of compressible cavitating flow field.The reliability of the numerical simulation method for compressible cavitating flows was verified by comparing it with experimental data from literature.Non-dimensional parameters,including cavitation numberσ,CN cavitation number,St number,and pressure loss coefficient K,were analyzed,and the results showed that the accuracy of the numerical simulation for pressure-velocity coupling calculation still needs to be improved.Under both shedding and condensation shock wave mechanisms,the growth of vortex rings was found to be the dissipative process after the detachment of the cavitation cloud,and the decay of vortex rings led to free vortices.The comparison of the two mechanisms showed that the deviation of non-dimensional parameters was smaller under the shedding mechanism,while there was a certain deviation under the condensation shock wave mechanism.The power spectral density analysis of the condensation shock wave mechanism revealed a-7/3 scaling law,while the shedding mechanism showed a-5/3 scaling law.
作者
张楚谦
陈勇刚
赵梁
Zhang Chuqian;Chen Yonggang;Zhao Liang(Civil Aviation Flight University of China,Guanghan 618307,China;Sichuan Key Laboratory of Civil Aircraft Fire Science and Safety Engineering,Guanghan 618307,China)
出处
《广东化工》
CAS
2024年第4期65-68,共4页
Guangdong Chemical Industry
基金
辽宁省教育厅科学研究一般项目(L2016017)
辽宁省自然科学基金资助项目(20170540591)
中国民用航空飞行学院科研基金面上项目(J2021-106,J2020-108)。
关键词
文丘里管
LES模型
回射流
凝结激波
空化数
压力损失系数
St数
功率谱密度分析
venturi tube
LES model
re-entrant jet
condensation shock
cavitation number
pressure loss coefficient
Strouhal number
power spectrum density
