摘要
We investigate the effects of viscosity and heat conduction on the onset and growth of Kelvin-Helmholtz instability (KHI) via an efficient discrete Boltzmann model.Technically,two effective approaches are presented to quantitatively analyze and understand the configurations and kinetic processes.One is to determine the thickness of mixing layers through tracking the distributions and evolutions of the thermodynamic nonequilibrium (TNE) measures;the other is to evaluate the growth rate of KHI from the slopes of morphological functionals.Physically,it is found that the time histories of width of mixing layer,TNE intensity,and boundary length show high correlation and attain their maxima simultaneously.The viscosity effects are twofold,stabilize the KHI,and enhance both the local and global TNE intensities.Contrary to the monotonically inhibiting effects of viscosity,the heat conduction effects firstly refrain then enhance the evolution afterwards.The physical reasons are analyzed and presented.
基金
Y. G.,C.L., H. L. and Z. L. acknowledge the support from the National Natural Science Foundation of China (Grant Nos.11875001,51806116, and 11602162)
Natural Science Foundation of Hebei Province (Grants Nos. A2017409014 and 2018J01654)
Natural Science Foundations of Hebei Educational Commission (Grant No.ZD2017001)
A. X. and G.Z.acknowledge the support from the National Natural Science Foundation of China (Grant No. 11772064)
CAEP Foundation (Grant No. CX2019033)
Science Challenge Project (Grant No.JCKY2016212A501)
the opening project of State Key Laboratory of Explosion Science and Technology (Beijing Institute of Technology, Grant No. KFJJ19-01M).
