1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
<HTML>
<CENTER><A HREF = "http://www.cfdem.com">LIGGGHTS WWW Site</A> - <A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LIGGGHTS Documentation</A> - <A HREF = "Section_commands.html#comm">LIGGGHTS Commands</A>
</CENTER>
<HR>
<H1>LIGGGHTS 2.X vs. LIGGGHTS 1.5.3 - syntax changes
</H1>
<H2>Introduction:
</H2>
<P>This is a short outline of the most important changes in LIGGGHTS 2.X
compared to LIGGGHTS 1.5.3 regarding the syntax of major commands. The
motivation for these changes was to make the script language more readable and to
improve extendability (in the sense of object oriented programming) with respect
to modelling approaches.
</P>
<H2>Commands covered by this tutorial:
</H2>
<LI>atom_style sphere (formerly atom_style granular)
<LI>dump mesh/stl (formerly dump stl)
<LI>dump mesh/vtk (formerly dump mesh/gran/VTK)
<LI>fix heat/gran
<LI>fix mesh/surface (formerly fix mesh/gran)
<LI>fix mesh/surface/stress (formerly fix mesh/gran/stressanalysis)
<LI>fix move/mesh (formerly fix move/mesh/gran)
<LI>fix wall/gran/*
<LI>pair_style gran/*
</UL>
<H2>Changes in syntax for each command:
</H2>
<P>Changes are indicated as follows
</P>
<PRE>OLD: old_syntax
NEW: new_syntax
</PRE>
<P>where <I>old_syntax</I> refers to the syntax used in LIGGGHTS 1.5.3 and before,
and <I>new_syntax</I> refers to the syntax used in LIGGGHTS 2.X
</P>
<HR>
<P><B>atom_style sphere (formerly atom_style granular):</B>
</P>
<PRE>OLD: atom_style granular
NEW: atom_style sphere
</PRE>
<P>NOTE: For compatibility reasons, the old syntax can still be used in LIGGGHTS 2.0
</P>
<P>For details, see <A HREF = "atom_style.html">atom_style sphere</A>.
</P>
<HR>
<P><B>dump mesh/stl:</B>
</P>
<PRE>OLD: dmpstl all stl 300 post/dump*.stl
NEW: dmpstl all mesh/stl 300 post/dump*.stl
</PRE>
<P>NOTE: For compatibility reasons, the old syntax can still be used in LIGGGHTS 2.0
</P>
<HR>
<P><B>dump mesh/vtk:</B>
</P>
<PRE>OLD: dmpstl all mesh/gran/VTK 300 post/dump*.stl id
NEW: dmpstl all mesh/vtk 300 post/dump*.stl id
</PRE>
<P>NOTE: For compatibility reasons, the old syntax can still be used in LIGGGHTS 2.0
</P>
<HR>
<P><B>fix heat/gran:</B>
</P>
<PRE>OLD: fix ID group-ID heat/gran 273.15
NEW: fix ID group-ID heat/gran initial_temperature 273.15
</PRE>
<PRE>OLD: fix ID group-ID heat/gran 273.15 + activate area correction via fix property/global
NEW: fix ID group-ID heat/gran initial_temperature 273.15 area_correction on
</PRE>
<HR>
<P><B>fix mesh/surface (formerly fix mesh/gran):</B>
</P>
<PRE>OLD: fix ID group-ID mesh/gran mesh.stl 1 1.0 0. 0. 0. 0. 0. 0.
NEW: fix ID group-ID mesh/surface file mesh.stl type 1
</PRE>
<PRE>OLD: fix ID group-ID mesh/gran mesh.stl 1 0.001 0. 0. 0. -90. 0. 0.
NEW: fix ID group-ID mesh/surface file mesh.stl type 1 scale 0.001 rotate axis 1. 0. 0. angle -90.
</PRE>
<PRE>OLD: fix ID group-ID mesh/gran mesh.stl 1 1.0 1. 2. 3. 0. 0. 0.
NEW: fix ID group-ID mesh/surface file mesh.stl type 1 move 1. 2. 3
</PRE>
<PRE>OLD: fix ID group-ID mesh/gran mesh.stl 1 1.0 0. 0. 0. 0. 0. 0. conveyor 5. 0. 0.
NEW: fix ID group-ID mesh/surface file mesh.stl type 1 surface_vel 5. 0. 0.
</PRE>
<PRE>OLD: fix ID group-ID mesh/gran mesh.stl 1 1.0 0. 0. 0. 0. 0. 0. rotate 0. 0. 0. 1. 0. 0. 5.
NEW: fix ID group-ID mesh/surface file mesh.stl type 1 surface_ang_vel origin 0. 0. 0. axis 1. 0. 0. omega 5.
</PRE>
<P>For details, see <A HREF = "fix_mesh_surface.html">fix mesh/surface</A>.
</P>
<HR>
<P><B>fix mesh/surface/stress (formerly fix mesh/gran/stressanalysis):</B>
</P>
<PRE>OLD: fix ID group-ID mesh/gran/stressanalysis mesh.stl 1 1.0 0. 0. 0. 0. 0. 0. finnie yes
NEW: fix ID group-ID fix mesh/surface/stress file mesh.stl type 1 wear finnie
</PRE>
<P>For details, see <A HREF = "fix_mesh_surface_stress.html">fix mesh/surface/stress</A>.
</P>
<HR>
<P><B>fix move/mesh (formerly fix move/mesh/gran):</B>
</P>
<PRE>OLD: fix ID group-ID move/mesh/gran wiggle -0.1 0. 0. 0.02 cad1 1
NEW: fix ID group-ID move/mesh mesh cad1 wiggle amplitude -0.1 0. 0. period 0.02
</PRE>
<PRE>OLD: fix ID group-ID move/mesh/gran rotate 0. 0. 0. 0. 0. 1. 0.05 cad1 1
NEW: fix ID group-ID move/mesh mesh cad1 rotate origin 0. 0. 0. axis 0. 0. 1. period 0.05
</PRE>
<PRE>OLD: fix ID group-ID move/mesh/gran linear 20. 20. 0. cad1 1
NEW: fix ID group-ID move/mesh mesh cad1 linear 20. 20. 0.
</PRE>
NOTES:
</UL>
<LI>The trailing "1" for the <I>old_syntax</I> was no longer used in LIGGGHTS 1.5.3
<LI>For compatibility reasons, the command name <I>fix move/mesh/gran</I> can be
used in LIGGGHTS 2.0. However, the syntax has to follow the LIGGGHTS 2.0 syntax.
<P>For details, see <A HREF = "fix_move_mesh.html">fix move/mesh</A>.
</P>
<HR>
<P><B>fix wall/gran/*:</B>
</P>
<PRE>OLD: fix ID group-ID wall/gran/hertz/history 1 0 mesh/gran 2 cad1 cad2
NEW: fix ID group-ID wall/gran/hertz/history mesh n_meshes 2 meshes cad1 cad2
</PRE>
<PRE>OLD: fix ID group-ID wall/gran/hertz/history 1 0 xplane -0.5 0.5 1
NEW: fix ID1 group-ID wall/gran/hertz/history type 1 xplane -0.5
fix ID2 group-ID wall/gran/hertz/history type 1 xplane 0.5
</PRE>
<PRE>OLD: fix ID group-ID wall/gran/hertz/history 3 0 xplane -0.5 0.5 1
NEW: fix ID1 group-ID wall/gran/hertz/history primitive type 1 xplane -0.5 rolling_friction cdt
fix ID2 group-ID wall/gran/hertz/history primitive type 1 xplane 0.5 rolling_friction cdt
</PRE>
<PRE>OLD: fix ID group-ID wall/gran/hertz/history 1 1 xplane -0.5 0.5 1
NEW: fix ID group-ID wall/gran/hertz/history primitive type 1 xplane -0.5 0.5 cohesion sjkr
</PRE>
<PRE>OLD: fix ID group-ID wall/gran/hertz/history 0 0 zcylinder 0.05 1
NEW: fix ID group-ID wall/gran/hertz/history primitive type 1 zcylinder 0.05 0. 0. tangential_damping off
</PRE>
NOTES:
</UL>
<LI>Same applies for hooke/history, hooke, hooke/history/simple, hertz/history/simple
<LI><I>sjkr</I> stands for 'simplified JKR (Johnson-Kendall-Roberts)' model, and <I>cdt</I> for
'constant directional torque' model
<LI>styles <I>xplane</I>, <I>yplane</I>, <I>zplane</I> take only one arg now (the wall position), if
you want two walls you have to use two fix commands
<LI>in addition to the existing style <I>zcylinder</I>, there is now <I>xcylinder</I> and
<I>ycylinder</I> as well
<LI><I>xcylinder</I> <I>ycylinder</I> and <I>zcylinder</I> take 3 args: the cylinder radius, and
the location of the axis in the other two dimensions
<P>For details, see <A HREF = "fix_wall_gran.html">fix wall/gran</A>.
</P>
<HR>
<P><B>pair_style gran/*:</B>
</P>
<PRE>OLD: pair_style gran/hertz/history 1 0
NEW: pair_style gran/hertz/history
</PRE>
<PRE>OLD: pair_style gran/hertz/history 3 0
NEW: pair_style gran/hertz/history rolling_friction cdt
</PRE>
<PRE>OLD: pair_style gran/hertz/history 1 1
NEW: pair_style gran/hertz/history cohesion sjkr
</PRE>
<PRE>OLD: pair_style gran/hertz/history 0 0
NEW: pair_style gran/hertz/history tangential_damping off
</PRE>
NOTES:
</UL>
<LI>Same applies for hooke/history, hooke, hooke/history/simple, hertz/history/simple
<LI><I>sjkr</I> stands for "simplified JKR (Johnson-Kendall-Roberts)" model, and <I>cdt</I> for "constant directional torque" model
<P>For details, see <A HREF = "pair_gran.html">pair_style gran</A>.
</P>
</HTML>
|
