fix dragforce/torque/field/compressible command

Syntax

fix ID group-ID dragforce/torque/field/compressible style_keyword style_values region region-ID field_keyword field_value ...

Keywords from fix_dragforce_field_compressible plus

  • In addition the following density field keyword/value pairs are allowed

  • field keyword = comp_torque and comp_Magnus

comp_torque value = 'yes' or 'no'
  compute and apply the drag torque to the particles
comp_Magnus value = 'yes' or 'no'
  compute and apply the Magnus force to the particles

Examples

fix  dragtorque all dragforce/torque/field/compressible Schiller_Naumann &
    viscosity 1.5e-5 density 1&
    region reg &
    binsize 0.1 file flowField.dat &
    file_coords cod_U.dat interpolate yes &
    rho_file rhoField.dat &
    SutherlandCoeff_viscRef 1.716e-5 SutherlandCoeff_Tref 273.15 SutherlandCoeff_S 110.4 &
    comp_torque yes comp_Magnus no

Description

Performs the same operations as fix_dragforce_field_compressible. In addition a drag torque which decreases the particles rotational velocity relative to the local fluid vorticity and a Magnus force may be computed.

  • These forces are computed by the following correlations. Drag torque

8 * pi * nu * rhoF * radius^3 * omegaRel

  • Magnus force

pi * rhoF * radius^3 * (uRel x omegaRel)

with the local fluid density rhoF, the fluid viscosity nu, the relative particle velocity uRel, the relative particle rotational velocity omegaRel, and the cross product operator x.

Restart, fix_modify, output, run start/stop

No information about this fix is written to binary restart files. No fix_modify option applies to this fix. This fix computes no output, which can be accessed by various output commands. No parameter of this fix can be used with the start/stop keywords of the run command.

Restrictions

none

Default

comp_torque = yes, comp_Magnus = yes