Academy
of Mathematics and Systems Science, CAS
Colloquia & Seminars
Speaker:
Prof. Qi Wang, Beijing Computational Science Research Center
Inviter:
明平兵
Title:
Numerical methods
for nonequilibrium models derived from the generalized Onsager principle
Time
& Venue:
2016.9.28 16:00-17:00
Z301
Abstract:
Equilibrium
thermodynamics is a well-established discipline. However, theories
for nonequilibrium phenomena are far from settled. There have not
been well-established physical laws like the three fundamental thermodynamical
laws for nonequilibrium phenomena. To established baseline principles
for developing theories for nonequilibrium phenomena, ones have resorted
to extend the equilibrium thermodynamic laws, especially, the second
law to near equilibrium phenomena or tried to set up prototypical
mathematical structures for admissible nonequilibrium thermodynamic
theories. These include the GENERIC and Poisson Bracket formulation
of nonequilibrium theories or the generalized Onsager principle. In
this talk, I will first discuss briefly what is the generalized Onsager
principle and its applicability to developing nonequilibrium theories
for physical systems. Then, I will discuss how numerical analysts
can exploit the mathematical structure in the models derived using
the generalized Onsager principle systematically. A new technique
termed the energy quadratization (EQ) will be introduced. I will illustrate
the idea using a few well-known models for multi-phase materials and
generalized hydrodynamics for complex fluid flows.