Two-dimensional Turbulence with Drag

dc.contributor.advisorOtt, Edwarden_US
dc.contributor.authorTsang, Yue-Kinen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.description.abstractWe consider the enstrophy cascade in forced two-dimensional turbulence with a linear drag force. In the presence of linear drag, the energy wavenumber spectrum drops with a power law faster than in the case without drag, and the vorticity field becomes intermittent, as shown by the anomalous scaling of the vorticity structure functions. Using a previous theory, we compare numerical simulation results with predictions for the power law exponent of the energy wavenumber spectrum and the scaling exponents of the vorticity structure functions $\zeta_{2q}$ obtained in terms of the distribution of finite time Lyapunov exponents. We also study, both by numerical experiment and theoretic al analysis, the multifractal structure of the viscous enstrophy dissipation in terms of its R\'{e}nyi dimension spectrum $D_q$ and singularity spectrum $f(\alpha)$. We derive a relation between $D_q$ and $\zeta_{2q}$, and discuss its relevance to a version of the refined similarity hypothesis. In addition, we obtain and compare theoretically and numerically derived results for the dependence on separation $r$ of the probability distribution of $\delta_{\V{r}}\omega$, the difference between the vorticity at two points separated by a distance $r$. Our numerical simulations are done on a $4096 \times 4096$ grid.en_US
dc.format.extent6220981 bytes
dc.subject.pqcontrolledPhysics, Fluid and Plasmaen_US
dc.subject.pqcontrolledPhysics, Atmospheric Scienceen_US
dc.subject.pqcontrolledPhysics, Generalen_US
dc.titleTwo-dimensional Turbulence with Dragen_US
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
5.93 MB
Adobe Portable Document Format