Nonequilibrium flow modelling: from weak perturbations towards extremal deviations from equilibrium

• 主讲人：Elena Kustova（Saint Petersburg State University）
• 举办方： Beijing-Saint Petersburg Mathematics Colloquium
• 时间： 2023-10-26 21:00 - 2023-10-26 22:00
• 地点： online

Recording: https://disk.pku.edu.cn:443/link/38AA9D9EF3F2BA33409D2C4504ABE900
Valid Until: 2023-11-29 23:59

 

Abstract：Nonequilibrium gas states arise in many problems of high-altitude aerodynamics, gas dynamics, low-temperature plasma, and micro-mechanical systems. The degree of deviation from equilibrium is determined by the gas rarefaction, as well as the relationship between the characteristic times of physical and chemical processes occurring in the gas and the time of change in the macroscopic flow characteristics. Depending on the kinetic scaling, models of various complexity can be developed.

This talk is devoted to the construction and implementation of mathematical models of nonequilibrium flows using a continuum approach based on the generalized Chapman-Enskog method, taking into account fast and slow processes. The following topics will be discussed: 1) Models of weakly nonequilibrium flows taking into account relaxation processes at the level of transport coefficients, in particular, bulk viscosity; 2) Models of highly nonequilibrium flows (state-to-state and multi-temperature) and the ways of improving their numerical efficiency; 3) Slip boundary conditions taking into account complex state-to-state vibrational-chemical kinetics in the gas phase and recombination/deactivation reactions on the surface.

 

 

Bio：Elena Vladimirovna Kustova is the Acting Head of the Faculty of Mathematics and Mechanics at Saint Petersburg State University (from 2022) being also head of the Department of Fluid  Mechanics and Aerodynamics. She graduated from Leningrad University in 1988 and got her PhD degree in 1993, DS degree in Mathematics in 2002. Starting from 2002 he has worked as a professor of the Department of Fluid Mechanics and Aerodynamics and heads this department starting from 2014. Elena Vladimirovna has a honorable degree of Professor of Russian Academy of Sciences. She has a big experience of working as a Visiting Professor in various universities of France, Italy and Brazil.

Prof. Kustova is author of more than 250 publications including two monographs; she mentored more than 50 diploma works and 6 PhD thesis.

Her main research interests are:

- Kinetic theory of transfer and relaxation processes in nonequilibrium reactive gases.

- Construction of strict self-consistent mathematical models of nonequilibrium currents with consideration of complex physico-chemical transformations.

- Research of heat and mass transfer on the surface of aircraft entering the atmosphere of Earth and Mars.

- Study of the speed of non-equilibrium processes.

- Development of software tools for the implementation of models of unequal gas dynamics.

- Methods of machine learning in non-equilibrium aeromechanics.