70th Annual Meeting of the APS Division of Fluid Dynamics
Volume 62, Number 14
Sunday–Tuesday, November 19–21, 2017;
Denver, Colorado
Session KP1: Poster Session I (3:20 - 4:05pm)
3:20 PM,
Monday, November 20, 2017
Room: E Concourse
Abstract ID: BAPS.2017.DFD.KP1.43
Abstract: KP1.00043 : Binary gas mixture in a high speed channel
Preview Abstract
Abstract
Author:
Dr. Sahadev Pradhan
(Chemical Technology Division, Bhabha Atomic Research Centre, Mumbai- 400 085)
The viscous, compressible flow in a 2D wall-bounded channel, with bottom
wall moving in the positive $x-$ direction, simulated using the direct
simulation Monte Carlo (DSMC) method, has been used as a test bed for
examining different aspects of flow phenomenon and separation performance of
a binary gas mixture at Mach number \textit{Ma }$=$\textit{ (U\textunderscore w / }$\backslash $\textit{sqrt(}$\gamma $\textit{ k\textunderscore B T\textunderscore w /m) }in the range\textit{ 0.1 \textless Ma \textless 30},
and Knudsen number \textit{Kn }$=$\textit{ 1/(}$\backslash $\textit{sqrt(2) }$\pi $\textit{ d\textasciicircum 2 n\textunderscore d H)} in the range \textit{0.1 \textless Kn \textless 10}. The generalized
analytical model is formulated which includes the fifth order differential
equation for the boundary layer at the channel wall in terms of master
potential ($\chi )$, which is derived from the equations of motion in a 2D
rectangular $(x - y)$ coordinate. The starting point of the analytical model is
the Navier-Stokes, mass, momentum and energy conservation equations in the
$(x - y)$ coordinate, where $x$ and $y$ are the streamwise and wall-normal directions,
respectively. The linearization approximation is used ((Pradhan {\&}
Kumaran\textit{, J. Fluid Mech -}2011); (Kumaran {\&} Pradhan, \textit{J. Fluid Mech -}2014)), where the equations of motion
are truncated at linear order in the velocity and pressure perturbations to
the base flow, which is an isothermal compressible Couette flow. Additional
assumptions in the analytical model include high aspect ratio \textit{(L \textgreater \textgreater H)}, constant
temperature in the base state (isothermal condition), and low Reynolds
number (laminar flow). The analytical solutions are compared with direct
simulation Monte Carlo (DSMC) simulations and found good agreement (with a
difference of less than 10{\%}), provided the boundary conditions are
accurately incorporated in the analytical solution.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2017.DFD.KP1.43