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
211
212
213
214
215
216
217
218
219
220
|
#!/usr/bin/env python3
from pathlib import Path
import multiprocessing
import re
import tempfile
import subprocess
import fnmatch
import shutil
import numpy as np
from pyelmer import elmer
import click
from scipy import constants
def enumerate_mesh_bodies(msh_file):
with open(msh_file, 'r') as f:
for line in f:
if line.startswith('$PhysicalNames'):
break
else:
raise ValueError('No physcial bodies found in mesh file.')
_num_names = next(f)
for line in f:
if line.startswith('$EndPhysicalNames'):
break
dim, _, line = line.strip().partition(' ')
tag, _, name = line.partition(' ')
yield name.strip().strip('"'), (int(dim), int(tag))
INPUT_EXT_MAP = {
'.grd': 1,
'.mesh*': 2,
'.ep': 3,
'.ansys': 4,
'.inp': 5,
'.fil': 6,
'.FDNEUT': 7,
'.unv': 8,
'.mphtxt': 9,
'.dat': 10,
'.node': 11,
'.ele': 11,
'.mesh': 12,
'.msh': 14,
'.ep.i': 15,
'.2dm': 16}
OUTPUT_EXT_MAP = {
'.grd': 1,
'.mesh*': 2,
'.ep': 3,
'.msh': 4,
'.vtu': 5}
def elmer_grid(infile, outfile=None, intype=None, outtype=None, cwd=None, **kwargs):
infile = Path(infile)
if outfile is not None:
outfile = Path(outfile)
if intype is None:
intype = str(INPUT_EXT_MAP[infile.suffix])
if outtype is None:
if outfile is not None and outfile.suffix:
outtype = str(OUTPUT_EXT_MAP[outfile.suffix])
else:
outtype = '2'
if outfile is not None:
kwargs['out'] = str(outfile)
args = ['ElmerGrid', intype, outtype, str(infile)]
for key, value in kwargs.items():
args.append(f'-{key}')
if isinstance(value, (tuple, list)):
args.extend(str(v) for v in value)
else:
args.append(str(value))
subprocess.run(args, cwd=cwd, check=True)
def elmer_solver(cwd):
subprocess.run(['ElmerSolver'], cwd=cwd)
@click.command()
@click.option('-d', '--sim-dir', type=click.Path(dir_okay=True, file_okay=False, path_type=Path))
@click.argument('mesh_file', type=click.Path(dir_okay=False, path_type=Path))
def run_capacitance_simulation(mesh_file, sim_dir):
physical = dict(enumerate_mesh_bodies(mesh_file))
if sim_dir is not None:
sim_dir = Path(sim_dir)
sim_dir.mkdir(exist_ok=True)
sim = elmer.load_simulation('3D_steady', 'coil_parasitics_sim.yml')
mesh_dir = '.'
mesh_fn = 'mesh'
sim.header['Mesh DB'] = f'"{mesh_dir}" "{mesh_fn}"'
sim.constants.update({
'Permittivity of Vacuum': str(constants.epsilon_0),
'Gravity(4)': f'0 -1 0 {constants.g}',
'Boltzmann Constant': str(constants.Boltzmann),
'Unit Charge': str(constants.elementary_charge)})
air = elmer.load_material('air', sim, 'coil_parasitics_materials.yml')
ro4003c = elmer.load_material('ro4003c', sim, 'coil_parasitics_materials.yml')
solver_electrostatic = elmer.load_solver('Electrostatics_Capacitance', sim, 'coil_parasitics_solvers.yml')
solver_electrostatic.data['Potential Difference'] = '1.0'
eqn = elmer.Equation(sim, 'main', [solver_electrostatic])
bdy_sub = elmer.Body(sim, 'substrate', [physical['substrate'][1]])
bdy_sub.material = ro4003c
bdy_sub.equation = eqn
bdy_ab = elmer.Body(sim, 'airbox', [physical['airbox'][1]])
bdy_ab.material = air
bdy_ab.equation = eqn
# boundaries
for name, identity in physical.items():
if (m := re.fullmatch(r'trace([0-9]+)', name)):
num = int(m.group(1))
bndry_m2 = elmer.Boundary(sim, name, [identity[1]])
bndry_m2.data['Capacitance Body'] = str(num)
boundary_airbox = elmer.Boundary(sim, 'FarField', [physical['airbox_surface'][1]])
boundary_airbox.data['Electric Infinity BC'] = 'True'
with tempfile.TemporaryDirectory() as tmpdir:
if sim_dir:
tmpdir = str(sim_dir)
sim.write_startinfo(tmpdir)
sim.write_sif(tmpdir)
# Convert mesh from gmsh to elemer formats. Also scale it from 1 unit = 1 mm to 1 unit = 1 m (SI units)
elmer_grid(mesh_file.absolute(), 'mesh', cwd=tmpdir, scale=[1e-3, 1e-3, 1e-3])
elmer_solver(tmpdir)
capacitance_matrix = np.loadtxt(tmpdir / 'capacitance.txt')
@click.command()
@click.option('-d', '--sim-dir', type=click.Path(dir_okay=True, file_okay=False, path_type=Path))
@click.argument('mesh_file', type=click.Path(dir_okay=False, path_type=Path))
def run_inductance_simulation(mesh_file, sim_dir):
physical = dict(enumerate_mesh_bodies(mesh_file))
if sim_dir is not None:
sim_dir = Path(sim_dir)
sim_dir.mkdir(exist_ok=True)
sim = elmer.load_simulation('3D_steady', 'coil_mag_sim.yml')
mesh_dir = '.'
mesh_fn = 'mesh'
sim.header['Mesh DB'] = f'"{mesh_dir}" "{mesh_fn}"'
sim.constants.update({
'Permittivity of Vacuum': str(constants.epsilon_0),
'Gravity(4)': f'0 -1 0 {constants.g}',
'Boltzmann Constant': str(constants.Boltzmann),
'Unit Charge': str(constants.elementary_charge)})
air = elmer.load_material('air', sim, 'coil_mag_materials.yml')
ro4003c = elmer.load_material('ro4003c', sim, 'coil_mag_materials.yml')
copper = elmer.load_material('copper', sim, 'coil_mag_materials.yml')
solver_current = elmer.load_solver('Static_Current_Conduction', sim, 'coil_mag_solvers.yml')
solver_magdyn = elmer.load_solver('Magneto_Dynamics', sim, 'coil_mag_solvers.yml')
solver_magdyn_calc = elmer.load_solver('Magneto_Dynamics_Calculations', sim, 'coil_mag_solvers.yml')
copper_eqn = elmer.Equation(sim, 'copperEqn', [solver_current, solver_magdyn, solver_magdyn_calc])
air_eqn = elmer.Equation(sim, 'airEqn', [solver_magdyn, solver_magdyn_calc])
bdy_trace = elmer.Body(sim, 'trace', [physical['trace'][1]])
bdy_trace.material = copper
bdy_trace.equation = copper_eqn
bdy_sub = elmer.Body(sim, 'substrate', [physical['substrate'][1]])
bdy_sub.material = ro4003c
bdy_sub.equation = air_eqn
bdy_ab = elmer.Body(sim, 'airbox', [physical['airbox'][1]])
bdy_ab.material = air
bdy_ab.equation = air_eqn
bdy_if_top = elmer.Body(sim, 'interface_top', [physical['interface_top'][1]])
bdy_if_top.material = copper
bdy_if_top.equation = copper_eqn
bdy_if_bottom = elmer.Body(sim, 'interface_bottom', [physical['interface_bottom'][1]])
bdy_if_bottom.material = copper
bdy_if_bottom.equation = copper_eqn
# boundaries
boundary_airbox = elmer.Boundary(sim, 'FarField', [physical['airbox_surface'][1]])
boundary_airbox.data['Electric Infinity BC'] = 'True'
boundary_vplus = elmer.Boundary(sim, 'Vplus', [physical['interface_top'][1]])
boundary_vplus.data['Potential'] = 1.0
boundary_vplus.data['Save Scalars'] = True
boundary_vminus = elmer.Boundary(sim, 'Vminus', [physical['interface_bottom'][1]])
boundary_vminus.data['Potential'] = 0.0
with tempfile.TemporaryDirectory() as tmpdir:
if sim_dir:
tmpdir = str(sim_dir)
sim.write_startinfo(tmpdir)
sim.write_sif(tmpdir)
# Convert mesh from gmsh to elemer formats. Also scale it from 1 unit = 1 mm to 1 unit = 1 m (SI units)
elmer_grid(mesh_file.absolute(), 'mesh', cwd=tmpdir, scale=[1e-3, 1e-3, 1e-3])
elmer_solver(tmpdir)
if __name__ == '__main__':
run_inductance_simulation()
|
