ორშაბათს, 9 მარტს, 15:00 საათზე ფიზიკის მცირე აუდიტორიაში (თსუ II კორპუსის #227 აუდიტორია) ჩატარდება სამეცნიერო სემინარი.
მოხსენების თემა: ენტროპიის ზონალურ და ტურბულენტურ კომპონენტებს შორის გადანაწილება;
Partition of enstrophy between zonal and turbulent components
მომხსენებელი:Professor Zensho Yoshida, Graduate School of Frontier Sciences, Department of Advanced Energy, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
Abstract: The partition of enstrophy between zonal (ordered) and wavy (turbulent) components of vorticity has been studied for the beta-plane model of two-dimensional barotropic flow. An analytic estimate of the minimum value for the zonal component has been derived. The energy, angular momentum, circulation, as well as the total enstrophy are invoked as constraints for the minimization of the zonal enstrophy. The corresponding variational principle has an interesting mathematical structure in that the target functional, the zonal enstrophy is not coercive with respect to the norm of enstrophy,by which the constraints work differently than usual variational principles. A discrete set of zonal enstrophy levels is generated by the energy constraint; each level is specified by an eigenvalue that represents the lamination period of zonal flow. However, the value itself of the zonal enstrophy level is a function of only angular momentum and circulation, being independent of the energy (and total enstrophy). Instead, the energy works in selecting the level (eigenvalue) of the relaxed state. Comparison with numerical simulations shows that the theory gives a proper estimate of the zonal enstrophy in the relaxed state.