Topical Problems of Fluid Mechanics


Institute of Thermomechanics AS CR, v.v.i.	CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics	MIO Université du Sud Toulon Var - AMU - CNRS - IRD	Czech Pilot centre ERCOFTAC

Second-Order Model for Atmospheric Turbulence without Critical Richardson Number
Caggio M., Schiavon M., Tampieri F., Bodnár T.
Abstract:
The purpose of this communication is to present a derivation of the non-dimensional vertical gradients of the mean wind speed and mean potential temperature expressed in terms of the so-called similarity functions for very stable conditions of the atmosphere where theoretical approaches provide conflicting results (see e.g. Luhar et al. [19]). The result is based on the analysis of the second-order model equations in the boundary layer approximations in which new heat flux equations are proposed. The model employs a recent closure for the pressure-temperature correlation, avoiding the issue of a critical treshold for the Richardson number.
Keywords:
atmospheric boundary layer, second-order closure model, turbulence parameterisations, strong strati cation, critical Richardson number

Fulltext: PDF DOI: https://doi.org/10.14311/TPFM.2021.002

In Proceedings Topical Problems of Fluid Mechanics 2021, Prague, 2021, Edited by Tomáš Bodnár, Tomáš Neustupa and David Šimurda, pp. 8-15 ISBN 978-80-87012-76-5 (Print) ISSN 2336-5781 (Print)