# Another comment on claims of a transition to the ultimate regime of heat transfer

## TL;DR

This paper critically examines recent claims of observing a transition to the ultimate heat transfer regime in 2D Rayleigh-Bénard convection simulations, questioning their validity and interpretation.

## Contribution

It provides a critical analysis challenging the evidence and conclusions of recent studies claiming to observe the ultimate regime in 2D convection.

## Key findings

- Questions the validity of the claimed transition to the ultimate regime
- Highlights potential issues in the interpretation of simulation results
- Suggests further scrutiny is needed for these claims

## Abstract

Claims made by Zhu et al., PRL 120, 144502, (2018), that they had found evidence of a transition to the so called "ultimate regime" in 2D simulations of Rayleigh-B\'enard convection, have recently been repeated by Lohse & Shishkina, Rev. Mod. Phys. 96, 03501 (2024). The author questions the validity of these claims.