81 lines
2.0 KiB
C++
81 lines
2.0 KiB
C++
/* ----------------------------------------------------------------------
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LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
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http://lammps.sandia.gov, Sandia National Laboratories
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Steve Plimpton, sjplimp@sandia.gov
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Copyright (2003) Sandia Corporation. Under the terms of Contract
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DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
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certain rights in this software. This software is distributed under
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the GNU General Public License.
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See the README file in the top-level LAMMPS directory.
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------------------------------------------------------------------------- */
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#ifdef FIX_CLASS
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FixStyle(viscosity,FixViscosity)
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#else
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#ifndef LMP_FIX_VISCOSITY_H
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#define LMP_FIX_VISCOSITY_H
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#include "fix.h"
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namespace LAMMPS_NS {
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class FixViscosity : public Fix {
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public:
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FixViscosity(class LAMMPS *, int, char **);
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~FixViscosity();
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int setmask();
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void init();
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void end_of_step();
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double compute_scalar();
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private:
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int me;
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int vdim,pdim,nbin,periodicity;
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int nswap;
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double vtarget;
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double prd,boxlo,boxhi;
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double slablo_lo,slablo_hi,slabhi_lo,slabhi_hi;
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double p_exchange;
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int npositive,nnegative;
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int *pos_index,*neg_index;
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double *pos_delta,*neg_delta;
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};
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}
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#endif
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#endif
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/* ERROR/WARNING messages:
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E: Illegal ... command
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Self-explanatory. Check the input script syntax and compare to the
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documentation for the command. You can use -echo screen as a
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command-line option when running LAMMPS to see the offending line.
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E: Fix viscosity swap value must be positive
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Self-explanatory.
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E: Fix viscosity vtarget value must be positive
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Self-explanatory.
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W: Fix viscosity comes before fix ave/spatial
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The order of these 2 fixes in your input script is such that
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fix viscosity comes first. If you are using fix ave/spatial
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to measure the velocity profile induced by fix viscosity, then
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this may cause a glitch in the profile since you are averaging
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immediately after swaps have occurred. Flipping the order
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of the 2 fixes typically helps.
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*/
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