u$_{s}$ u - u s p -5.0 5.0 y -7.0 < x < +7.0 Figure 1: Schematic stationary shockwave. Cold fluid enters at the left cold boundary, with speed u$_{s}$ ; hot fluid leaves at the right hot boundary, with speed u$_{s}$ − u$_{p}$ . We choose a coordinate frame which moves leftward, at speed u$_{s}$ relative to the laboratory frame. The shockwave remains stationary in this coordinate frame. Figure 2: Stationary shockwave. Snapshot from a 10-row molecular dynamics simulation with a periodic height of 10 √ 3 / 4. The simulations analyzed in the text are based on 80-row molecular dynamics with a periodic height of 80 √ 3 / 4. I. INTRODUCTION A leftmoving piston, impacting a fluid with velocity − u$_{p}$ , generates a leftmoving shock- wave with velocity − u$_{s}$ . Throughout this paper we analyze such a shockwave from the viewpoint of a coordinate system moving leftward, so as to keep pace with the shock. See Figures 1 and 2. In this special uniformly-translating coordinate frame the shockwave is stationary, simplifying theoretical analyses. One-dimensional stationary shockwaves 1–14 provide a useful computational laboratory for the study of stationary far-from-equilibrium states. In such a shockwave a cold fluid is converted irreversibly to a hot one. As the fluid moves from left to right, in the shock-centered coordinate frame of the Figures, at speed u ( x ), the x coordinate increases; typically, the corresponding density, the longitudinal component of the pressure tensor, and the energy all increase too, in just such a way that the spatial structure of the wave is stationary: { u = ˙ x, ˙ ρ, ˙ P$_{xx}$, ˙ e } > 0 , ( ∂u/∂t )$_{x}$ = 0 ; ( ∂ρ/∂t )$_{x}$ = 0 ; ( ∂P$_{xx}$/∂t )$_{x}$ = 0 ; ( ∂P$_{yy}$/∂t )$_{x}$ = 0 ; ( ∂e/∂t )$_{x}$ = 0 .