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A Shear Stress Reynolds' Limit Formula

Analysis of PDEs 2020-07-17 v1 Mathematical Physics math.MP

Abstract

Historically, meteorological and climate studies have been prompted by the need for understanding precipitation to have better logistics in food production. Despite all efforts, nonlinearity in atmosphere dynamics is still a source of uncertainty. On the other hand, aeronautical science studies the boundary layer separation through the \emph{shear stress}. In this work, a mathematical interpretation of methods in classical aerodynamics theory in terms of successive layers of \emph{diffeomorphisms} over \emph{Lipschitz domains} allows us to estimate the boundary layer's \emph{shear stress}, τd\tau^{*}_d and τm\tau^{*}_m, in dry and humid atmospheric conditions without assuming that there is not a convective derivative term in the conservation of momentum equation or that the gaseous boundary layer is incompressible: τd=Uh (1U22cpd T0)19/25,τm=Uh (1U22cpm T0)19/25, \tau^{*}_d = \frac{U}{h}\ \left(1-\frac{U^2}{2c_{pd}\ T_0}\right)^{19/25}, \hspace{7pt} \tau^{*}_m = \frac{U}{h}\ \left(1-\frac{U^2}{2c_{pm}\ T_0}\right)^{19/25}, where hh is the boundary layer's height, T0T_0 is the surface temperature, UU is the \emph{free stream velocity}; cpdc_{pd} is the \emph{specific heat at constant pressure for dry air} and cpmc_{pm} is the \emph{specific heat at constant pressure for moist air}. Furthermore, if R^m\hat{R}_m is a \emph{gas constant for moist air} and p0p_0 is the pressure at the surface, the density ρp0T02bb11R^m1[1(U2/2cphT0)]b(b1)1\rho \hspace{2pt} \cong \hspace{2pt} p_0 \hspace{2pt} T_0^{\frac{2b}{b-1}-1} \hspace{2pt} \hat{R}_{m}^{-1} \hspace{2pt} \left[1-\left(U^2/2c_{ph}T_0\right)\right]^{\frac{b}{(b-1)}-1} for b=1.405b=1.405. Moreover, this opens the possibility of finding a different deterministic family of atmosphere natural convection models.

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Cite

@article{arxiv.2007.08099,
  title  = {A Shear Stress Reynolds' Limit Formula},
  author = {Carla Victoria Valencia-Negrete},
  journal= {arXiv preprint arXiv:2007.08099},
  year   = {2020}
}
R2 v1 2026-06-23T17:09:27.445Z