/[escript]/trunk/finley/test/python/seismic_wave.py
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Annotation of /trunk/finley/test/python/seismic_wave.py

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Revision 862 - (hide annotations)
Tue Oct 3 06:01:30 2006 UTC (13 years, 1 month ago) by gross
File MIME type: text/x-python
File size: 7467 byte(s)
bug in mesh generator fixed.
1 gross 842 """
2     seismic wave propagation
3    
4     @var __author__: name of author
5     @var __licence__: licence agreement
6     @var __url__: url entry point on documentation
7     @var __version__: version
8     @var __date__: date of the version
9     """
10    
11     __copyright__=""" Copyright (c) 2006 by ACcESS MNRF
12     http://www.access.edu.au
13     Primary Business: Queensland, Australia"""
14     __license__="""Licensed under the Open Software License version 3.0
15     http://www.opensource.org/licenses/osl-3.0.php"""
16     __author__="Lutz Gross, l.gross@uq.edu.au"
17     __url__="http://www.iservo.edu.au/esys/escript"
18     __version__="$Revision$"
19     __date__="$Date$"
20    
21     from esys.escript import *
22     from esys.escript.linearPDEs import LinearPDE
23     from esys.finley import Brick
24 gross 843 import time
25 gross 842
26 gross 844 output=True
27     n_end=10000
28 gross 843
29 gross 862 resolution=5000. # number of elements per m
30 gross 850 l=100000. # width and length m
31 gross 842 h=30000. # height in m
32 gross 844 o=1 # element order
33 gross 842
34     rho_bedrock=8e3
35     mu_bedrock=1.7e11
36     lambda_bedrock=1.7e11
37    
38     l_x_water=10000 # length of water in x
39     l_y_water=10000 # length of water in y
40     h_water=max(2000,resolution) # depth of water region
41    
42     water_tag=2
43     rho_water=1e3
44     mu_water=0.
45     lambda_water=1.e9
46    
47     d0_sand=10000 # thickness of sand region on surface
48     d_sand=max(2000,resolution) # thickness of sand layer under the water
49    
50     sand_tag=3
51     rho_sand=5e3
52     mu_sand=1.5e10
53     lambda_sand=1.5e10
54    
55    
56     # location and geometrical size of event:
57 gross 862 xc=[l*0.5,l*0.5,h*0.3]
58     src_radius = 2*resolution
59 gross 842 # direction of event:
60 gross 862 event=numarray.array([0.,0.,1.])*1.e6
61 gross 842 # time and length of the event
62     tc_length=2.
63     tc=sqrt(5.*tc_length)
64 gross 843 if output:
65     print "event location = ",xc
66     print "radius of event = ",src_radius
67     print "time of event = ",tc
68     print "length of event = ",tc_length
69     print "direction = ",event
70 gross 842
71 gross 862 t_end=30.
72 gross 842
73     def getDomain():
74     """
75     this defines a dom as a brick of length and width l and hight h
76    
77    
78     """
79 gross 843 global netotal
80 gross 844 v_p_bedrock=sqrt((2*mu_bedrock+lambda_bedrock)/rho_bedrock)
81     v_p_sand=sqrt((2*mu_sand+lambda_sand)/rho_sand)
82     v_p_water=sqrt((2*mu_water+lambda_water)/rho_water)
83 gross 842
84 gross 844 print v_p_bedrock,v_p_sand,v_p_water
85    
86     ne_l_x_bed=int((l-d0_sand-l_x_water)/resolution+0.5)
87     ne_l_y_bed=int((l-d0_sand-l_y_water)/resolution+0.5)
88     ne_h_bed=int((h-d_sand-h_water)/resolution+0.5)
89    
90     ne_l_sand=int(d0_sand*v_p_bedrock/v_p_sand/resolution+0.5)
91     ne_h_sand=int(d_sand*v_p_bedrock/v_p_sand/resolution+0.5)
92    
93     ne_l_x_water=int(l_x_water*v_p_bedrock/v_p_water/resolution+0.5)
94     ne_l_y_water=int(l_y_water*v_p_bedrock/v_p_water/resolution+0.5)
95     ne_h_water=int(h_water*v_p_bedrock/v_p_water/resolution+0.5)
96    
97     ne_l_x=ne_l_x_bed+ne_l_sand+ne_l_x_water
98     ne_l_y=ne_l_y_bed+ne_l_sand+ne_l_y_water
99     ne_h=ne_h_bed+ne_h_sand+ne_h_water
100    
101     print ne_l_x,ne_l_x_bed,ne_l_sand,ne_l_x_water
102     print ne_l_y,ne_l_y_bed,ne_l_sand,ne_l_y_water
103     print ne_h,ne_h_bed,ne_h_sand,ne_h_water
104    
105     netotal=ne_l_x*ne_l_y*ne_h
106     if output: print "grid : %s x %s x %s (%s elements)"%(ne_l_x,ne_l_y,ne_h,netotal)
107     dom=Brick(ne_l_x,ne_l_y,ne_h,l0=o*ne_l_x,l1=o*ne_l_y,l2=o*ne_h,order=o)
108     x=dom.getX()
109    
110     x0=x[0]
111     x0_new = (l-d0_sand-l_x_water)/(o*ne_l_x_bed)*x0
112     msk=whereNonPositive(x0-o*ne_l_x_bed)
113     x0_new = x0_new * msk + (d0_sand/(o*ne_l_sand)*(x0-o*ne_l_x_bed)+l-d0_sand-l_x_water)*(1.-msk)
114     msk=whereNonPositive(x0-o*(ne_l_x_bed+ne_l_sand))
115     x0_new = x0_new * msk + (l_x_water/(o*ne_l_x_water)*(x0-o*(ne_l_x_bed+ne_l_sand))+l-l_x_water)*(1.-msk)
116    
117     x1=x[1]
118     x1_new = (l-d0_sand-l_y_water)/(o*ne_l_y_bed)*x1
119 gross 862 msk=whereNonPositive(x1-o*ne_l_y_bed)
120 gross 844 x1_new = x1_new * msk + (d0_sand/(o*ne_l_sand)*(x1-o*ne_l_y_bed)+l-d0_sand-l_y_water)*(1.-msk)
121     msk=whereNonPositive(x1-o*(ne_l_y_bed+ne_l_sand))
122     x1_new = x1_new * msk + (l_y_water/(o*ne_l_y_water)*(x1-o*(ne_l_y_bed+ne_l_sand))+l-l_y_water)*(1.-msk)
123    
124     x2=x[2]
125     x2_new = (h-d_sand-h_water)/(o*ne_h_bed)*x2
126 gross 862 msk=whereNonPositive(x2-o*ne_h_bed)
127     x2_new = x2_new * msk + (d_sand/(o*ne_h_sand)*(x2-o*ne_h_bed)+h-d_sand-h_water)*(1.-msk)
128     msk=whereNonPositive(x2-o*(ne_h_bed+ne_h_sand))
129     x2_new = x2_new * msk + (h_water/(o*ne_h_water)*(x2-o*(ne_h_bed+ne_h_sand))+h-h_water)*(1.-msk)
130 gross 844
131     dom.setX(x0_new*[1,0,0]+x1_new*[0,1,0]+x2_new*[0,0,1])
132    
133 gross 842 fs=Function(dom)
134     x=Function(dom).getX()
135     fs.setTags(sand_tag,wherePositive(x[0]-(l-l_x_water-d0_sand)) \
136     *wherePositive(x[1]-(l-l_y_water-d0_sand)) \
137     *wherePositive(x[2]-(h-h_water-d_sand)))
138     fs.setTags(water_tag,wherePositive(x[0]-(l-l_x_water)) \
139     *wherePositive(x[1]-(l-l_y_water)) \
140     *wherePositive(x[2]-(h-h_water)))
141     return dom
142    
143     def getMaterialProperties(dom):
144     rho =Scalar(rho_bedrock,Function(dom))
145     rho.setTaggedValue(sand_tag,rho_sand)
146     rho.setTaggedValue(water_tag,rho_water)
147    
148     lame_mu =Scalar(mu_bedrock,Function(dom))
149     lame_mu.setTaggedValue(sand_tag,mu_sand)
150     lame_mu.setTaggedValue(water_tag,mu_water)
151    
152     lame_lambda=Scalar(lambda_bedrock,Function(dom))
153     lame_lambda.setTaggedValue(sand_tag,lambda_sand)
154     lame_lambda.setTaggedValue(water_tag,lambda_water)
155    
156     return rho,lame_mu,lame_lambda
157    
158    
159     def wavePropagation(dom,rho,lame_mu,lame_lambda):
160     x=Function(dom).getX()
161     # ... open new PDE ...
162     mypde=LinearPDE(dom)
163     mypde.setSolverMethod(LinearPDE.LUMPING)
164     k=kronecker(Function(dom))
165     mypde.setValue(D=k*rho)
166    
167     v_p=sqrt((2*lame_mu+lame_lambda)/rho)
168 gross 843 if output: print "v_p=",v_p
169 gross 842 v_s=sqrt(lame_mu/rho)
170 gross 843 if output: print "v_s=",v_s
171 gross 842 dt=(1./5.)*inf(dom.getSize()/v_p)
172 gross 843 if output: print "time step size = ",dt
173 gross 842 # ... set initial values ....
174     n=0
175     t=0
176 gross 862 t_write=0
177 gross 842 # initial value of displacement at point source is constant (U0=0.01)
178     # for first two time steps
179     u =Vector(0.,Solution(dom))
180     u_last=Vector(0.,Solution(dom))
181    
182 gross 843 starttime = time.clock()
183     while t<t_end and n<n_end:
184     if output: print n+1,"-th time step t ",t+dt," max u and F: ",Lsup(u),
185 gross 842 # ... get current stress ....
186     eps=symmetric(grad(u))
187     stress=lame_lambda*trace(eps)*k+2*lame_mu*eps
188     # ... force due to event:
189     F=exp(-((t-tc)/tc_length)**2)*exp(-(length(x-xc)/src_radius)**2)*event
190 gross 843 if output: print Lsup(F)
191 gross 842 # ... get new acceleration ....
192     mypde.setValue(X=-stress,Y=F)
193     a=mypde.getSolution()
194     # ... get new displacement ...
195     u_new=2*u-u_last+dt**2*a
196     # ... shift displacements ....
197     u_last,u=u,u_new
198     # ... save current acceleration in units of gravity and displacements
199 gross 843 if output:
200 gross 862 if t>=t_write:
201     saveVTK("disp.%i.vtu"%(n/10),displacement=u, amplitude=length(u))
202     t_write+=0.5
203 gross 842 t+=dt
204     n+=1
205    
206 gross 843 endtime = time.clock()
207     totaltime = endtime-starttime
208     global netotal
209     print ">>number of elements: %s, total time: %s, per time step: %s <<"%(netotal,totaltime,totaltime/n)
210 gross 842 if __name__ =="__main__":
211     dom=getDomain()
212     rho,lame_mu,lame_lambda=getMaterialProperties(dom)
213     wavePropagation(dom,rho,lame_mu,lame_lambda)

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