#
49th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting

## Volume 63, Number 5

##
Monday–Friday, May 28–June 1 2018;
Ft. Lauderdale, Florida

### Session M01: Poster Session II

4:00 PM,
Wednesday, May 30, 2018

Room: Hall D

Abstract ID: BAPS.2018.DAMOP.M01.76

### Abstract: M01.00076 : DSMC Simulations of High Mach Number Taylor-Couette Flow

Preview Abstract
Abstract

####
Author:

Dr. Sahadev Pradhan

(Chemical Technology Division, Bhabha Atomic Research Centre, Mumbai- 400 085, India)

The main focus of this work is to characterise the Taylor-Couette flow of an
ideal gas between two coaxial cylinders at Mach number \textit{Ma }$=$\textit{ (U\textunderscore w / }$\backslash
$\textit{sqrt\textbraceleft kb T\textunderscore w / m\textbraceright )}in the range 0.01 \textless Ma \textless , and Knudsen number \textit{Kn }$=$\textit{ (1 / (}$\backslash
$\textit{sqrt\textbraceleft 2\textbraceright }$\backslash $\textit{pi d\textasciicircum 2 n\textunderscore d (r\textunderscore 2 - r\textunderscore 1))) }in the range 0.001 \textless Kn \textless , using
two-dimensional (2D) direct simulation Monte Carlo (DSMC) simulations. Here,
\textit{r\textunderscore 1}and \textit{r\textunderscore 2}are the radius of inner and outer cylinder respectively,
\textit{U\textunderscore w}is the circumferential wall velocity of the inner cylinder,
\textit{T\textunderscore w}is the isothermal wall temperature, \textit{n\textunderscore d}is the number density of the gas
molecules, $m$and $d$ are the molecular mass and diameter, and \textit{kb}is the Boltzmann
constant. The cylindrical surfaces are specified as being diffusely
reflecting with the thermal accommodation coefficient equal to one. In the
present analysis of high Mach number compressible Taylor-Couette flow using
DSMC method, wall slip in the temperature and the velocities are found to be
significant. Slip occurs because the temperature/velocity of the molecules
incident on the wall could be very different from that of the wall, even
though the temperature/velocity of the reflected molecules is equal to that
of the wall. Due to the high surface speed of the inner cylinder,
significant heating of the gas is taking place. The gas temperature
increases until the heat transfer to the surface equals the work done in
moving the surface. The highest temperature is obtained near the moving
surface of the inner cylinder at a radius of about (1.26 r\textunderscore
1).

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2018.DAMOP.M01.76