title: Shocks in supersonic sand.
abstract: We measure time-averaged velocity, density, and temperature fields for steady granular flow past a wedge. We find the flow to be supersonic with a speed of granular pressure disturbances (sound speed) equal to about 10% of the flow speed, and we observe shocks nearly identical to those in a supersonic gas. Molecular dynamics simulations of Newton's laws yield fields in quantitative agreement with experiment. A numerical solution of Navier-Stokes-like equations agrees with a molecular dynamics simulation for experimental conditions excluding wall friction.
authors.affiliation: Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Erin C
authors.initials: EC
authors.lastname: Rericha
authors.forename: Chris
authors.initials: C
authors.lastname: Bizon
authors.forename: Mark D
authors.initials: MD
authors.lastname: Shattuck
authors.forename: Harry L
authors.initials: HL
authors.lastname: Swinney