孤立型透镜的地转适应研究：对博格（Burger）数和初始几何

Geostrophic adjustment of an isolated axisymmetric lens was examined to better understand the dependence of radial displacements and the adjusted velocity on Burger number and the geometry of initial conditions. The behavior of the adjustment was examined using laboratory experiments and numerical simulations, which were in turn compared to published analytical solutions. Three defining length scales of the initial conditions were used to distinguish between various asymptotic behaviors for large and small Burger number: the Rossby radius of deformation, the horizontal length scale of the initial density defect, and the horizontal length scale of the initial pressure gradient. Numerical simulations for the fully nonlinear time dependent adjustment agreed both qualitatively and quantitatively with analogous analytical solutions. For large Burger number, similar agreement was found in laboratory experiments. Results show that a broad range of final states can result from different initial geometries, depending on the values of the relevant length scales, and the Burger number computed from initial conditions. For Burger number much larger or smaller than unity, differences between different initial geometries can readily exceed an order of magnitude for both displacement and velocity. 德国LaVision PIV/PLIF粒子成像测速场仪