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Fluctuations in a fluid with a thermal gradient

Jaechul Oh·Guenter Ahlers
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Abstract

We report measurements of the temperature fluctuations in a horizontal layer of a pure fluid confined between parallel plates and heated from below. Consistent with earlier work we found that the structure factor $S_T(q)$ (the square of the modulus of the Fourier transform of the temperature field) was consistent with $S_T(q) \sim q^{-4}$ for large horizontal wavenumbers $q$. As $q$ decreased, $S(q)$ increased less rapidly, passed through a maximum, and then approached zero. The results agree qualitatively, but not quantitatively, with the predictions of Ortiz de Zárate and Sengers.

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Jaechul Oh, Guenter Ahlers. 2002-09-04. Fluctuations in a fluid with a thermal gradient. https://arxiv.org/abs/cond-mat/0209104

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