def run_pde(self):
t0 = self.parameter.simulation_start_time # Start time for simulation
current_time = t0 # Variable to store the current time
t_step = self.parameter.time_step
pde_equation = self.pde_equation
sol_variable = self.solution_variable
if self.parameter.plotting:
viewer = Viewer(vars=sol_variable, datamin=0, datamax=1.)
viewer.plotMesh()
# source_flag = True # currently not implemented
while current_time < t0 + self.parameter.simulation_duration:
### This code was to allow boundary flux to change, but non-flux boundaries are not working
# if source_flag and current_time > self.parameter.source_end_time:
# sol_variable = self.define_solution_variable(sol_variable, boundary_source='no flux')
# sol_variable.faceGrad.constrain(0 * self.mesh.faceNormals, self.mesh.exteriorFaces)
pde_equation.solve(var=sol_variable, dt=t_step) # solve one time step
# Increment time
previous_time = current_time
current_time += t_step
# Check for change in convection data
if self.detect_change_in_convection_data(previous_time, current_time):
pde_equation = self.define_ode(current_time)
# Check if the solution should be saved
if self.detect_save_time(previous_time, current_time):
self.add_current_state_to_save_file(current_time)
if self.parameter.plotting:
viewer.plot()
# If the final time step goes beyond the duration, do a shorter finishing step.
if current_time > t0 + self.parameter.simulation_duration:
t_step = current_time - (t0 + self.parameter.simulation_duration)
current_time = t0 + self.parameter.simulation_duration # set current time to the final time
pde_equation.solve(var=sol_variable, dt=t_step) # solve one time step
print('Current time step: {}, finish time: {}'.format(current_time, self.parameter.simulation_duration))
# At completion, save the final state
self.add_current_state_to_save_file(current_time)
print('PDE solving complete')
#We create a viewer to see the results
#.. index::
# module: fipy.viewers
if __name__ == '__main__':
if doBlob:
try:
viewer = Viewer(vars=phi, datamin=-1.5, datamax=1.)
viewer.plot()
raw_input("Irregular circular mesh. Press <return> to proceed..."
) # doctest: +GMSH
except:
print "Unable to create a viewer for an irregular mesh (try Matplotlib2DViewer or MayaviViewer)"
elif doCirc:
try:
viewer = Viewer(vars=phi, datamin=-1, datamax=1.)
viewer.plotMesh()
raw_input("Irregular circular mesh. Press <return> to proceed..."
) # doctest: +GMSH
except:
print "Unable to create a viewer for an irregular mesh (try Matplotlib2DViewer or MayaviViewer)"
else:
viewer = Viewer(vars=phi, datamin=0., datamax=1.)
viewer.plot()
#and solve the equation by repeatedly looping in time:
if doBlob:
timeStepDuration = 10 * 0.9 * 0.05**2 / (2 * D)
elif doCirc:
timeStepDuration = 10 * 0.9 * cellSize**2 / (2 * D)
else:
timeStepDuration = 10 * 0.9 * dx**2 / (2 * D)