Thermal turbulence in mercury.
نویسندگان
چکیده
We studied thermal turbulence in a low Prandtl number, Pr, fluid using liquid Hg (Pr 0.024). For Rayleigh numbers (106 , Ra , 108), the histogram of temperature fluctuations at the center of the cell (aspect ratio 1), and the scaling laws for the Nusselt number and the large scale flow, all showed He-like hard turbulence. However, the cascade range of the frequency spectrum of the temperature fluctuations was smaller than expected. Direct measurement showed that the thermal and viscous boundary layers had crossed, which may explain the peculiar scaling.
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ورودعنوان ژورنال:
- Physical review letters
دوره 76 9 شماره
صفحات -
تاریخ انتشار 1996