Files
simpeg/simpegEM/FDEM/FDEM.py
T

129 lines
3.4 KiB
Python

from SimPEG import Problem, Solver, Utils, np, sp
from scipy.constants import mu_0
from SurveyFDEM import SurveyFDEM, DataFDEM, FieldsFDEM
def omega(freq):
"""Change frequency to angular frequency, omega"""
return 2.*np.pi*freq
class ProblemFDEM_e(Problem.BaseProblem):
"""
Frequency-Domain EM problem - E-formulation
.. math::
\dcurl E + i \omega B = 0 \\\\
\dcurl^\\top \MfMui B - \MeSig E = \Me \j_s
"""
def __init__(self, model, **kwargs):
Problem.BaseProblem.__init__(self, model, **kwargs)
solType = 'b'
storeTheseFields = 'e'
surveyPair = SurveyFDEM
dataPair = DataFDEM
solveOpts = {'factorize':False, 'backend':'scipy'}
####################################################
# Mass Matrices
####################################################
@property
def MfMui(self): return self._MfMui
@property
def Me(self): return self._Me
@property
def MeSigma(self): return self._MeSigma
@property
def MeSigmaI(self): return self._MeSigmaI
def makeMassMatrices(self, m):
#TODO: hardcoded to sigma as the model
sigma = self.model.transform(m)
self._Me = self.mesh.getEdgeInnerProduct()
self._MeSigma = self.mesh.getEdgeInnerProduct(sigma)
# TODO: this will not work if tensor conductivity
self._MeSigmaI = Utils.sdiag(1/self.MeSigma.diagonal())
#TODO: assuming constant mu
self._MfMui = self.mesh.getFaceInnerProduct(1/mu_0)
####################################################
# Internal Methods
####################################################
def getA(self, freq):
"""
:param int fInd: Frequency index
:rtype: scipy.sparse.csr_matrix
:return: A
"""
return self.mesh.edgeCurl.T*self.MfMui*self.mesh.edgeCurl + 1j*omega(freq)*self.MeSigma
def getRHS(self, freq):
#TODO: this needs to also depend on your transmitter!
return -1j*omega(freq)*self.Me*self.j_s
def fields(self, m, useThisRhs=None):
RHS = useThisRhs or self.getRHS
self.makeMassMatrices(m)
F = FieldsFDEM(self.mesh, self.survey)
for freq in self.survey.freqs:
A = self.getA(freq)
b = self.getRHS(freq)
e = Solver(A, options=self.solveOpts).solve(b)
F[freq, 'e'] = e
#TODO: check if mass matrices needed:
b = -1./(1j*omega(freq))*self.mesh.edgeCurl*e
F[freq, 'b'] = b
return F
def Jvec(self, m, v, u=None):
if u is None:
u = self.fields(m)
Jv = self.dataPair(self.survey)
for i, freq in enumerate(self.survey.freqs):
e = u[freq, 'e']
A = self.getA(freq)
solver = Solver(A, options=self.solveOpts)
for tx in self.survey.getTransmitters(freq):
dMe_dsig = self.mesh.getEdgeInnerProductDeriv(m, v=e)
dsig_dm = self.model.transformDeriv(m)
b = 1j*omega(freq) * ( dMe_dsig * ( dsig_dm * v ) )
Ab = solver.solve(b)
P = tx.projectFieldsDeriv(self.mesh, u)
Jv[tx] = -P*Ab
return Utils.mkvc(Jv)
def Jtvec(self, m, v, u=None):
if u is None:
u = self.fields(m)
raise NotImplementedError('Jtvec todo!')