Abstract: In this paper, temperature oscillation is found in theexperiment. The experimental research focus on the critical Ma number ofonset of temperature oscillation, and discuss the transition of temperatureoscillation as the Ma increase. The experiment result shows that onset oftemperature oscillation in silicon oil with different physical propertiesmeet the same law. The super critical temperature oscillation showsdifferent transition routes in the different fluid, but the same route isperformed in the same fluid with different depths. Besides, convectionpattern and its transition are studied by particle trace method.