Large Scale Circulation in a Rectangular Enclosure With Periodic Boundary Temperature

Abstract

An experiment in a rectangular basin of water is used to demonstrate that a largescale circulation will result from a zeromean thermal forcing. The thermal force is a spatially periodic pattern of heating and cooling at the top surface, achieved with an interdigitated array of hot and cold tubes. The experimental results show a very robust, steady flow with ascending flows at each end of the tank and a single descending jet near the left wall. These results suggest that smallscale forcing in surfacedriven flows may result in significant largescale subsurface motion.