Spatial Correlation of Fluctuations and Formation of Dissipative Structures in Nonequilibrium Reaction Diffusion Systems and Hydrodynamic Systems

点击翻译按钮获取中文摘要

1.We formulate nonequilibrium thermodynamics of multi-component fluids by generalizing entropy in order that entropy is a function of barycentric flow and diffusion flows. This generalization enables us to derive constitutive equation for the relaxation of diffusion flows in the presence of inertial effects.2.The macroscopic description of a system with chemical reactions predicts that if the detailed balance conditon is violated, then nonequilibrium spatial correlation between concentrations of reactants may appear. We made molecular dynamics simulations of such correlations in a model sysem of reactiing hard spheres. We indeed found the long range correlations, which was predicted by the hydrodynamic description. There is some deviation in a short distance due to kinetic effects.Starting from the Langevin equation a nonlinear evolution equation describing the mean square distance of initially close tagged particles in a turbulent medium is obtained. The initial-t^3 and intermediate exponential growth of the mean square distance subsist even under the presence of stable drift.