EXPERIMENTAL INVESTIGATION ON THE CHAOTIC PHENOMENA IN THE WAKE OF A NATURAL THERMAL CONVECTION FLOW

摘要

Chaotic phenomena in the wake of thermal convection flow fields above a heating fiat plate were investigated experimentally. A newly developed electron beam fluorescence technique (EBF) was used to simultaneously measure density fluctuation at 7 points in a cross section above the plate. Correlation dimensions,intermittence coefficients, Fourier spectrum have been obtained for different Grashof numbers. Spatial distribution of correlation dimensions are presented. The experimental result shows that there is a certain relationship between the density fluctuation and the Gr number. And time-spacial characteristic of chaos evolution is also given.