Polymer heat transport enhancement in thermal convection: the case of Rayleigh-Taylor turbulence.
نویسندگان
چکیده
We study the effects of polymer additives on turbulence generated by the ubiquitous Rayleigh-Taylor instability. Numerical simulations of complete viscoelastic models provide clear evidence that the heat transport is enhanced up to 50% with respect to the Newtonian case. This phenomenon is accompanied by a speed-up of the mixing layer growth. We give a phenomenological interpretation of these results based on small-scale turbulent reduction induced by polymers.
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ورودعنوان ژورنال:
- Physical review letters
دوره 104 18 شماره
صفحات -
تاریخ انتشار 2010