摘要
使用格子玻尔兹曼方法对二维不混溶、不可压缩流体的Kelvin-Helmholtz(K-H)不稳定性进行数值模拟。以卷起高度H作为参考值,研究了密度比、表面张力、切应力对流体K-H不稳定性内产生Rayleigh-Taylor(R-T)不稳定性的影响。研究结果显示,密度比对两种不稳定性耦合起决定性作用。密度比接近1时,K-H不稳定性中不会产生R-T不稳定性,随着密度比增大,K-H不稳定性中开始产生R-T不稳定性。表面张力系数的增大对流体产生K-H不稳定性及两种不稳定性的耦合的卷起高度变化没有影响,但会对流体向内运动起抑制作用,且卷起流体的厚度明显增加。切应力对两种流体不稳定性的耦合起抑制作用。
By using the lattice Boltzmann method,the Kelvin-Helmholtz instability of two-dimensional immiscible and incompressible fluids was numerically simulated.Taking the rolling height H as a reference value,the effects of density ratio,surface tension and shear stress on the appearance of Rayleigh-Taylor(R-T)instability in Kelvin-Helmholtz(K-H)instability was studied.The results show that the density ratio plays a decisive role in the coupling effect of the two instabilities.When the density ratio is close to 1,the R-T instability does not occur in the K-H instability.When the density ratio increases,the R-T instability begins to occur in the K-H instability.An increase in the surface tension coefficient has no effect either on the K-H instability,or on the coupling height variation of the two instabilities,but it has an inhibitory effect on the inward movements of the fluids,and the thickness of the rolled fluid is significantly increased.The shear stress has an inhibitory effect on the coupling of the K-H instability and R-T instability.
作者
陈妍璐
谢玉仙
尚文强
张莹
CHEN Yanlu;XIE Yuxian;SHANG Wenqiang;ZHANG Ying(School of Mechatronics Engineering,Nanchang University,Nanchang 330031,China;School of Energy Engineering,Zhejiang University,Hangzhou 310027,China)
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2019年第5期74-80,共7页
Chinese Internal Combustion Engine Engineering
基金
国家自然科学基金项目(11562011,51566012)
江西省自然科学基金项目(20181BAB206031)~~
