高普朗特数薄层热卷流发展的剖析
We present an experimental study of thedynamics of a plume generated from a small heat source ina high Prandtl number fluid with a strongly temperaturedependentviscosity. The velocity field was determinedwith particle image velocimetry, while the temperaturefield was measured using differential interferometry andthermochromic liquid crystals. The combination of thesedifferent techniques run simultaneously allows us to identifythe different stages of plume development, and tocompare the positions of key-features of the velocity field(centers of rotation, maximum vorticity locations, stagnationpoints) respective to the plume thermal anomaly, forPrandtl numbers greater than 103. We further show that thethermal structure of the plume stem is well predicted by theconstant viscosity model of Batchelor (Q J R Met Soc 80:339–358, 1954) for viscosity ratios up to 50.1 Introduction