Evidence map›Paper›PMID 41171847›Full record

ArticleProceedings of the National Academy of Sciences of the United States of America2025

On the absence of the ultimate regime in turbulent thermal convection.

Harshit Tiwari, Lekha Sharma, Mahendra K Verma

Abstract read
In one paragraph

Article in Proceedings of the National Academy of Sciences of the United States of America, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. On the absence of the ultimate regime in turbulent thermal convection.Proceedings of the National Academy of Sciences of the United States of America · 2025
    Article
4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Harshit TiwariDepartment of Physics, Indian Institute of Technology Kanpur, Kanpur 208016, India.ORCID 0009-0002-0116-9476
Lekha SharmaDepartment of Physics, Indian Institute of Technology Kanpur, Kanpur 208016, India.ORCID 0000-0001-5543-4138
Mahendra K VermaDepartment of Physics, Indian Institute of Technology Kanpur, Kanpur 208016, India.ORCID 0000-0002-3380-4561

Funding

Anusandhan National Research Foundation SERB/PHY/2021473Anusandhan National Research Foundation SERB /PHY/2023488
6 · The paper itself

Abstract

Quantifying heat transport in turbulent convection remains a challenge. The two competing models of heat transport predict that the nondimensional heat flux, known as the Nusselt number (Nu), is proportional to [Formula: see text] (classical scaling) and [Formula: see text] (ultimate-regime scaling), where [Formula: see text] is the Rayleigh number. Some experiments and simulations report that the Nusselt number transitions from near classical scaling, [Formula: see text], to a larger power law when the boundary layer turns turbulent near [Formula: see text]. However, others find [Formula: see text] scaling to continue for larger Ra. In this work, we perform a comparative study of Rayleigh-Bénard, compressible, and periodic convection in two and three dimensions using direct numerical simulations. We show that up to [Formula: see text] in two dimensions and up to [Formula: see text] in three dimensions, the positive and negative energy fluxes in Rayleigh-Bénard and compressible convection are nearly equal. However, in the distribution function, the positive fluxes have longer tails than the negative ones, and the differences between the positive and negative fluxes scale as [Formula: see text], which leads to [Formula: see text]. The above robust and universal properties, even in the presence of a logarithmic layer in compressible convection, indicate a likely absence of the ultimate regime in turbulent thermal convection. In contrast, periodic convection, which is related to the ultimate regime, exhibits a predominantly positive heat flux.

Indexed as

compressible convectionRayleigh–Benard convectionturbulent convectionturbulent heat transportultimate regime of convection

Identifiers

PMID41171847
PMCPMC12595450

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.