Files
simpeg/simpegPF/Magnetics.py
T

83 lines
2.0 KiB
Python

from SimPEG import Problem, Utils
import BaseMag
from scipy.constants import mu_0
class MagneticsDiffSecondary(Problem.BaseProblem):
"""Secondary field approach using differential equations!"""
dataPair = BaseMag.BaseMagData
modelPair = BaseMag.BaseMagModel
def __init__(self, mesh, model, **kwargs):
Problem.BaseProblem.__init__(mesh, model, **kwargs)
self._Pbc, self._Pin, self._Pout = /
self.mesh.getBCProjWF('neumann', discretization='CC')
Dface = self.mesh.faceDiv
Mc = Utils.sdiag(self.mesh.vol)
self._Div = Mc*Dface*self.Pin.T*self.Pin
@property
def Pbc(self): return self._Pbc
@property
def Pin(self): return self._Pin
@property
def Pout(self): return self._Pout
@property
def Div(self): return self._Div
@property
def MfMuI(self): return self._MfMuI
@property
def Mfmu0(self): return self._Mfmu0
def makeMassMatrices(self, m):
mu = self.model.transform(m)
Mfmui = self.mesh.getFaceInnerProduct(1./mu)
#TODO: this will break if tensor mu
self._MfmuI = Utils.sdiag(1./Mfmui.diagonal())
self._Mfmu0 = self.mesh.getFaceInnerProduct(1/mu_0)
def getRHS(self):
b0 = self.data.B0
B0 = np.r_[b0[0]*np.ones(M3.nFx),
b0[1]*np.ones(M3.nFy),
b0[2]*np.ones(M3.nFz)]
Dface = self.mesh.faceDiv
Mc = Utils.sdiag(self.mesh.vol)
Bbc = CongruousMagBC(M3, np.array([Box, Boy, Boz]), chi)
rhs = -self.Div*self.MfmuI*self.Mfmu0*B0 + self.Div*B0 - Mc*Dface*self.Pout.T*Bbc
def getA(self, m):
"""
GetA creates and returns the A matrix for the Magnetics problem
The A matrix has the form:
.. math::
\mathbf{A} = \mathbf{D}\mu\mathbf{G}u
"""
return -self.Div*self.MfmuI*self.Div.T
def fields(self, m):
self.makeMassMatrices(m)
# F = self.getInitialFields()
# return self.forward(m, self.getRHS, self.calcFields, F=F)