Submission of 2 articles on vertical convection

We submitted two papers presenting work done during Arman Khoubani’s PhD thesis.

Article on vertical convection regimes

The first paper was submitted to the Journal of Fluid Mechanics and the submitted version is on ArXiv here .

Title: Vertical convection regimes in a rectangular cavity: Prandtl and aspect ratio dependance

Authors: Arman Khoubani, Ashwin Vishnu Mohanan, Pierre Augier and Jan-Bert Flór


Vertical convection, often also called lateral convection, is the fluid motion that is induced by the heating and cooling of two opposed vertical boundaries of a rectangular cavity. In this numerical study, we consider the linear stability of the steady two-dimensional flow reached at Rayleigh numbers of \(O(108)\) . This flow consists of two plume motions near the boundaries and a linear stable temperature stratification in the interior. As a function of the Prandtl number, Pr, and the height-to-width aspect ratio of the domain, A, the base flow (steady state) of each case is computed and linear simulations are used to obtain the properties of the leading linear mode of instability.

The flow regimes show a rich variation with Prandtl number and aspect ratio. These regimes depend on whether the plumes generate a circulation in the entire cavity, detach from the horizontal boundaries or the corner regions, and further on whether the oscillation frequency of the instability is slower (or faster) than the buoyancy frequency of the stratification in the interior, and allows for the presence of internal waves (or not), Accordingly, the regime is called slow or fast, respectively. Internal wave allow for the coupling between the top and bottom plumes, and their absence implies asymmetry in part of the regimes. Six essentially different flow regimes are found in the range of \(0.1\leq Pr≤4\) and \(0.5≤A≤2\) .

Article on our new tool Snek5000

The second article was submitted on the Journal of Open-Source Software (JOSS).

Title: Snek5000: a new Python framework for Nek5000

Authors: Ashwin Vishnu Mohanan, Arman Khoubani and Pierre Augier


Computational fluid dynamics (CFD) simulations are essential tools in various scientific and engineering disciplines. Nek5000 is a CFD Fortran code based on spectral element methods with a proven track record in numerous applications. In this article, we present Snek5000, a Python package designed to streamline the management and visualization of fluid dynamics simulations based on Nek5000. The package builds upon the functionality of Nek5000 by providing a user-friendly interface for launching and restarting simulations, loading simulation data, and generating figures and movies. This paper introduces Snek5000, discusses its design principles, and highlights its impact on the scientific community.