Book 217

This book reviews the approach to the kinetic simulation of nonequilib­ rium processes in the planetary atmospheres which the authors developed and dealt with since the 1970s. The results of this study, which are focused on the nonequilibrium collisional processes in the atmospheres of planets and comets, are thoroughly reviewed and discussed. Many specific problems of atmospheric modeling, involving numerical evaluation of aeronomic pro­ cesses, are addressed and compared with the available experimental data. The kinetic approach proved to be especially effective to model the in­ teraction of the incident shortwave solar radiation with the rarefied gas of planetary upper atmospheres. It involves various processes of photolysis, en­ ergetic electron impacts, and accompanying numerous chemical reactions, as well as processes occurring in the intermediate ("transition") zones of planetary and cometary gas envelopes. The underlying mathematical treat­ ment is based on the stochastic approach for the solution of the Boltzmann­ type equation and implies the development of the efficient algorithms for its computer simulation. Some results of this study were previously summa­ rized in the monograph issued in Russian (Marov et al. , 1990) and later in the review paper published in Space Science Reviews (Marov et al. , 1996). The basic principles of stochastic simulation were first developed in the field of rarefied gas dynamics and were successfully applied to the solution of some engineering problems of aerodynamics and heat transfer.

Book 269

Space exploration and advanced astronomy have dramatically expanded our knowledge of outer space and made it possible to study the indepth mechanisms underlying various natural phenomena caused by complex interaction of physical-chemical and dynamical processes in the universe. Huge breakthroughs in astrophysics and the planetary s- ences have led to increasingly complicated models of such media as giant molecular clouds giving birth to stars, protoplanetary accretion disks associated with the solar system’s formation, planetary atmospheres and circumplanetary space. The creation of these models was promoted by the development of basic approaches in modern - chanics and physics paralleled by the great advancement in the computer sciences. As a result, numerous multidimensional non-stationary problems involving the analysis of evolutionary processes can be investigated using wide-range numerical experiments. Turbulence belongs to the most widespread and, at the same time, the most complicated natural phenomena, related to the origin and development of organized structures (- dies of different scale) at a definite flow regime of fluids in essentially non-linear - drodynamic systems. This is also one of the most complex and intriguing sections of the mechanics of fluids. The direct numerical modeling of turbulent flows encounters large mathematical difficulties, while the development of a general turbulence theory is hardly possible because of the complexity of interacting coherent structures. Three-dimensional non-steady motions arise in such a system under loss of la- nar flow stability defined by the critical value of the Reynolds number.

Book 389

This book focuses on the development of continuum models of natural turbulent media. It provides a theoretical approach to the solutions of different problems related to the formation, structure and evolution of astrophysical and geophysical objects. A stochastic modeling approach is used in the mathematical treatment of these problems, which reflects self-organization processes in open dissipative systems. The authors also consider examples of ordering for various objects in space throughout their evolutionary processes.

This volume is aimed at graduate students and researchers in the fields of mechanics, astrophysics, geophysics, planetary and space science.


v. 217

This text reviews the approach to the kinetic simulation of nonequilibrium processes in the planetary atmospheres which the authors developed and have dealt with between 1970 and the late-1990s. The results of this study, which are focused on the nonequilibrium collisional processes in the atmospheres of planets and comets, are thoroughly reviewed and discussed. Many specific problems of atmospheric modelling, involving numerical simulation of aeronomic processes, are addressed and compared with the available experimental data. The kinetic approach proved to be especially effective in modelling the interaction of the incident shortwave solar radiation with the rarefied gas of planetary upper atmospheres. It involves various processes of photolysis, energetic particle impacts, and numerous accompanying chemical reactions. The underlying mathematical treatment is based on the stochastic approach for the solution of the Boltzmann-type equation and implies the development of efficient algorithms for its computer simulation.
New or upgraded methods and algorithms for addressing the relevant problems of non-equilibrium gas kinetics were developed and successfully implemented for the simulation of a wide range of aeronomical processes. The volume is primarily intended for professional scholars and graduate students in space sciences, planetary astronomy and aeronomy and should also be useful to some target groups dealing with mechanics, gas dynamics, and computer modelling of versatile physical processes and who wish to expand the areas of their immediate interests.