000014790 001__ 14790
000014790 005__ 20161115100202.0
000014790 04107 $$aeng
000014790 046__ $$k2016-08-21
000014790 100__ $$aShrira, Victor
000014790 24500 $$aSpectral evolution of random wave fields: Kinetic equations vs. direct numerical simulations (INVITED)

000014790 24630 $$n24.$$p24th International Congress of Theoretical and Applied Mechanics - Book of Papers
000014790 260__ $$bInternational Union of Theoretical and Applied Mechanics, 2016
000014790 506__ $$arestricted
000014790 520__ $$2eng$$aWe examine how accurately the kinetic equations describe evolution of random weakly nonlinear waves in fluids and solids. To this end we simulate numerically long-term evolution of wave spectra without forcing using three different models: (i) the classical kinetic equation (KE); (ii) the generalised kinetic equation (gKE) valid also when the wave spectrum is changing rapidly; (iii) the DNS based on the Zakharov integrodifferential equation for water waves (DNS-ZE). (DNS-ZE does not rely on any statistical assumptions. As the initial conditions we choose two spectra with the same frequency distribution and different degrees of directionality. All three approaches demonstrate very close evolution of integral characteristics of spectra. However, there are notable systematic differences (e.g. the broadening of angular spectra is much faster for the kinetic equations), which suggests the presence and significance of coherent interactions not accounted for by the established closure for the kinetic equations.

000014790 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000014790 653__ $$a

000014790 7112_ $$a24th International Congress of Theoretical and Applied Mechanics$$cMontreal (CA)$$d2016-08-21 / 2016-08-26$$gICTAM2016
000014790 720__ $$aShrira, Victor
000014790 8560_ $$ffischerc@itam.cas.cz
000014790 8564_ $$s57993$$uhttps://invenio.itam.cas.cz/record/14790/files/TS.FM16-3.02.pdf$$yOriginal version of the author's contribution as presented on CD,  page 1608, code TS.FM16-3.02
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000014790 962__ $$r13812
000014790 980__ $$aPAPER