Fluctuations and transport in a stirred fluid with a mean gradient.
نویسندگان
چکیده
The effective thermal diffusivity D and the probability distribution of temperature fluctuations are measured in a stirred fluid across which a temperature gradient is maintained. A distinct mixing transition is observed for D as a function of Reynolds number R. Above the transition, the distribution is strongly non-Gaussian and approaches an exponential exp( —(bT(/P(), where P is the local temperature gradient and ( the correlation length.
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عنوان ژورنال:
- Physical review letters
دوره 67 25 شماره
صفحات -
تاریخ انتشار 1991