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Applicability of Taylor's hypothesis in thermally driven turbulence.

ABSTRACT: In this paper, we show that, in the presence of large-scale circulation (LSC), Taylor's hypothesis can be invoked to deduce the energy spectrum in thermal convection using real-space probes, a popular experimental tool. We perform numerical simulation of turbulent convection in a cube and observe that the velocity field follows Kolmogorov's spectrum (k-5/3). We also record the velocity time series using real-space probes near the lateral walls. The corresponding frequency spectrum exhibits Kolmogorov's spectrum (f-5/3), thus validating Taylor's hypothesis with the steady LSC playing the role of a mean velocity field. The aforementioned findings based on real-space probes provide valuable inputs for experimental measurements used for studying the spectrum of convective turbulence.

SUBMITTER: Kumar A

PROVIDER: S-EPMC5936933 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Applicability of Taylor's hypothesis in thermally driven turbulence.

Kumar Abhishek A Verma Mahendra K MK

Royal Society open science 20180418 4

In this paper, we show that, in the presence of large-scale circulation (LSC), Taylor's hypothesis can be invoked to deduce the energy spectrum in thermal convection using real-space probes, a popular experimental tool. We perform numerical simulation of turbulent convection in a cube and observe that the velocity field follows Kolmogorov's spectrum (<i>k</i><sup>-5/3</sup>). We also record the velocity time series using real-space probes near the lateral walls. The corresponding frequency spect ...[more]

PMID: 29765668

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