title: Nonequilibrium thermohydrodynamic effects on the Rayleigh-Taylor instability in compressible flows.
abstract: The effects of compressibility on Rayleigh-Taylor instability (RTI) are investigated by inspecting the interplay between thermodynamic and hydrodynamic nonequilibrium phenomena (TNE, HNE, respectively) via a discrete Boltzmann model. Two effective approaches are presented, one tracking the evolution of the local TNE effects and the other focusing on the evolution of the mean temperature of the fluid, to track the complex interfaces separating the bubble and the spike regions of the flow. It is found that both the compressibility effects and the global TNE intensity show opposite trends in the initial and the later stages of the RTI. Compressibility delays the initial stage of RTI and accelerates the later stage. Meanwhile, the TNE characteristics are generally enhanced by the compressibility, especially in the later stage. The global or mean thermodynamic nonequilibrium indicators provide physical criteria to discriminate between the two stages of the RTI.
authors.affiliation: National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P. O. Box 8009-26, Beijing 100088, China.|School of Mathematics and Computer Science, Fujian Normal University, Fuzhou 350007, China.
authors.forename: Huilin
authors.initials: H
authors.lastname: Lai
authors.affiliation: National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P. O. Box 8009-26, Beijing 100088, China.|Center for Applied Physics and Technology, MOE Key Center for High Energy Density Physics Simulations, College of Engineering, Peking University, Beijing 100871, China.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Xu
authors.affiliation: National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P. O. Box 8009-26, Beijing 100088, China.
authors.forename: Guangcai
authors.initials: G
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P. O. Box 8009-26, Beijing 100088, China.|North China Institute of Aerospace Engineering, Langfang 065000, China.
authors.forename: Yanbiao
authors.initials: Y
authors.lastname: Gan
authors.affiliation: National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P. O. Box 8009-26, Beijing 100088, China.
authors.forename: Yangjun
authors.initials: Y
authors.lastname: Ying
authors.affiliation: Istituto Applicazioni Calcolo, CNR, Viale del Policlinico 137, 00161 Roma, Italy.
authors.forename: Sauro
authors.initials: S
authors.lastname: Succi