| 2 | Kinetic Simulation of Nonequilibrium Kelvin-Helmholtz Instability显示文摘The recently developed discrete Boltzmann method(DBM), which is based on a set of uniform linear evolution equations and has high parallel efficiency, is employed to investigate the dynamic nonequilibrium process of Kelvin-Helmholtz instability(KHI). It is found that, the relaxation time always strengthens the global nonequilibrium(GNE), entropy of mixing, and free enthalpy of mixing. Specifically, as a combined effect of physical gradients and nonequilibrium area, the GNE intensity first increases but decreases during the whole life-cycle of KHI. The growth rate of entropy of mixing shows firstly reducing, then increasing, and finally decreasing trends during the KHI process. The trend of the free enthalpy of mixing is opposite to that of the entropy of mixing. Detailed explanations are:(i) Initially,binary diffusion smooths quickly the sharp gradient in the mole fraction, which results in a steeply decreasing mixing rate.(ii) Afterwards, the mixing process is significantly promoted by the increasing length of material interface in the evolution of the KHI.(iii) As physical gradients are smoothed due to the binary diffusion and dissipation, the mixing rate reduces and approaches zero in the final stage. Moreover, with the increasing Atwood number, the global strength of viscous stresses on the heavy(light) medium reduces(increases), because the heavy(light) medium has a relatively small(large) velocity change. Furthermore, for a smaller Atwood number, the peaks of nonequilibrium manifestations emerge earlier, the entropy of mixing and free enthalpy of mixing change faster, because the KHI initiates a higher growth rate. | 林传栋 Kai H.Luo 甘延标 刘枝朋 | 2019 | Communications in Theoretical Physics2019，71，1： | 2 |
| 6 | Contribution of piezoelectric effect,electrostriction and ferroelectric/ferroelastic switching to strain-electric field response of dielectrics显示文摘This paper presents a thorough study of the strain response of different types of electroceramics during dynamical electrical loading.It highlights important aspects to take into account in the experimental methodology and outlines general guidelines for the discussion and interpretation of the results.The contributions of piezoelectric effect,electrostriction and ferroelectric/ferroelastic domain switching to the strain produced during the application of an alternating electric field are discussed by describing the strainelectric field(S-E)loops of different dielectric ceramics in which each of these contributions are predominant.In particular,attention is given to the description of the strain evolution in the characteristic'butterfly loops'typically shown by ferroelectric materials.The strain-polarization loop is indicated as a useful means to reveal the interconnection between strain and polarization state during dynamical electrical loading.Strain rate is suggested as a powerful tool to obtain more detailed information regarding the mechanisms of the electric field-induced strain. | G.Viola T.Saunders X.Wei K.B.Chong H.Luo M.J.Reece H.Yan | 2013 | Journal of Advanced Dielectrics2013，3，1： | 1 |
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