Simulation of 3d granular dissipative gas under different kinds of excitations & with different number of balls N .

Results 1 to 18:

R. Liu, M. Hou, P. Evesque, Lab MSSMat, UMR 8579 CNRS, Ecole Centrale Paris, 92295 CHATENAY-MALABRY, France, e-mail: pierre.evesque@ecp.fr

Abstract: This group of papers publishes a series of simulations on the dynamics of N equal-size spheres (D=1) in a 3d rectangular cell (L_x=20D, L_y=20D, L_z=60D) excited along z in 0 gravity.(N=100, 500, 1000, 1200, 2000, 3000, 4000, 4500). Different Oz excitation kinds have been used (symmetric and non symmetric bi-parabolic, symmetric and non symmetric saw teeth, thermal wall). No rotation is included, dissipation is introduced via a restitution coefficient e= -V’_n/V_n , where V’_n and V_n are the relative ball speed along normal to ball centres after and before collision. The papers are organised as follow : # 1,3,5,7,9,11,13 deal respectively with the number density distribution(1,2), V_z distribution (3,4), V_x (5,6), local V_z mean (7,8) in ± z directions, local sum of V_z (9,10), local T^±(z) in ±z directions, local P_z^±(z) in ±z directions, under bi-parabolic excitation (under sawteeth excitation). Booklet # 15-18, concern thermal excitation; #15 concerns V_z and V_x distribution at different z; local V_z Mean and local sum of V_z (flow) are published in #16; #17 concerns T^±(z) (i.e. local mean of V^±_z²) and P^±(z) (i.e. local sum of V^±_z²), and #18 the n_z distribution.

The simulations start at a given time from a random state which does not correspond to steady state. Curves are given after different laps of time, so that evolution to steady state can be determined. It occurs that few of these simulations (those with larger number of spheres) are not yet reaching the steady state even at the end of simulation.

Pacs # : 5.40 ; 45.70 ; 62.20 ; 83.70.Fn

poudres & grains 17 (1-18), 1-561 (Juillet 2009)