Showing 21 - 30 of 59
The DSMC (direct simulation Monte Carlo) method for rarefied gas dynamics is studied. The behaviour of the underlying stochastic particle system is determined by three main components – the time step between subsequent collisions, the random mechanism for the choice of the collision partners,...
Persistent link: https://www.econbiz.de/10010749555
Due to the mathematical complexity of the Boltzmann equation for inelastic hard spheres, a kinetic model has recently been proposed whereby the collision rate (which is proportional to the relative velocity for hard spheres) is replaced by an average velocity-independent value. The resulting...
Persistent link: https://www.econbiz.de/10010588469
The linear Boltzmann equation for elastic and/or inelastic scattering is applied to derive the distribution function of a spatially homogeneous system of charged particles spreading in a host medium of two-level atoms and subjected to external electric and/or magnetic fields. We construct a...
Persistent link: https://www.econbiz.de/10010588498
The aim of this work is to analyze the entropy, entropy flux and entropy rate of granular materials within the frameworks of the Boltzmann equation and continuum thermodynamics. It is shown that the entropy inequality for a granular gas that follows from the Boltzmann equation differs from the...
Persistent link: https://www.econbiz.de/10010588566
Several discrete models for relativistic binary mixtures are introduced. These models possess a correct number of conservation laws, so that they are without non-physical invariants. Some models for elastic scattering of radiation are proposed. Invariant functionals for a model with 8+5 momenta...
Persistent link: https://www.econbiz.de/10010589172
This article deals with the problem of temperature jump and slip velocity at the wall in gas/surface interaction. A consistent modelling of an impermeable surface involving an anisotropic scattering kernel developed in previous works is used to establish boundary conditions in unstructured...
Persistent link: https://www.econbiz.de/10010589242
The problem concerning the propagation of sound waves in a binary mixture of monatomic ideal gases is studied by using a kinetic model of the Boltzmann equation which corresponds to the two-fluid hydrodynamic theory. Comparison of the sound propagation results with the available experimental...
Persistent link: https://www.econbiz.de/10010589683
The hierarchy of moment equations derived from the nonlinear Boltzmann equation is solved for a gas of Maxwell molecules undergoing a stationary Poiseuille flow induced by an external force in a pipe. The solution is obtained as a perturbation expansion in powers of the force (through third...
Persistent link: https://www.econbiz.de/10010590171
The present paper considers the theoretical description of the propagation of sound waves in a one component monatomic gas. The interatomic potential is assumed to vary as the inverse fourth power of the interatomic separation, that is for so-called Maxwell molecules. The eigenvalues and...
Persistent link: https://www.econbiz.de/10010590453
Recent observations have indicated that the traditional equilibrium market hypothesis (EMH; also known as Efficient Market Hypothesis) is unrealistic. It is shown here that it is the analog of a Boltzmann equation in physics, thus having some bad properties of mean-field approximations like a...
Persistent link: https://www.econbiz.de/10010590750