A Comparison of Laboratory Experiments and Numerical Simulations of Steady Baroclinic Waves Produced in a Differentially Heated Rotating Fluid Annulus

Abstract

Qualitative and quantitative comparisons are made between laboratory measurements and numericalsolutions of steady rotating annulus flows. The governing equations of the fluid with the Boussinesq approximation are solved numerically by the finite difference method on nonuniform grids. The comparisons as to some characteristics of baroclinic waves such as rates of radial heat transport and drift periods of waves, which are measured by reducing probe effects to a negligible extent, demonstrate the reliability of the numerical model. Numerical results of internal structures of steady baroclinic waves are presented on the basis of this model verification and compared with experimental results. Comparisons reveal that not only probe drag but also heat leakage modifies flow fields to a considerable extent. Analyses made by using data obtained by simulations indicate that (1) the inward heat transport by the deviatorid motion overcomes the outward heat transport by the indirect circulation and plays anssential role in the heat transport to the inner cylinder; (2) the deviatoric motion as well as the mean meridional circulation transports angular momentum to the axis of the relative angular momentum jet; and (3) the conversion rate from deviatoric kinetic energy to zonal kinetic energy is positive at lower rotation rates but it becomes negative at higher rotation rates.