Exploring the physics of multiscale flows at the molecular level.

Two new applications of high performance computing based on the DSMC approach were presented in the Graeme Bird Plenary Lecture and are summarized in this paper. The paper first discusses the importance of bimodality in the velocity distribution function in characterizing unsteady shock oscillations as well as their role in understanding transitioning laminar shock-boundary layer flows. A second computational problem of the neutralization of a low-temperature ion beam plasma using the particle-in-cell approach is discussed and again the non-Maxwellian behavior of plasma electrons is shown to change the behavior of unsteady electron solitary waves. The paper looks both back and forwards in time and provides some assessment of the fundamental role of particle kinetic approaches in nonequilibrium gas dynamics. [ABSTRACT FROM AUTHOR]