Problem getting start

[qingqi-code]

Greetings Dr. Jeff,

I am a PhD student interested in flow in porous media and I want to implement OpenPNM in my research. But I am struggling at the very beginning. I am trying to run the getting started tutorial and failed. Here is the code and issue:

import openpnm as op

# Define geometrical parameters
Lc = 1e-4
Nx, Ny, Nz = (10, 10, 10)

# Generate network, geometry, phase, and physics
pn = op.network.Cubic(shape=[Nx, Ny, Nz], spacing=Lc)
geo = op.geometry.StickAndBall(network=pn, pores=pn.Ps, throats=pn.Ts)
Hg = op.phases.Mercury(network=pn)
phys = op.physics.Standard(network=pn, phase=Hg, geometry=geo)

# Create algorithm and run simulation
mip = op.algorithms.Porosimetry(network=pn, phase=Hg)
mip.set_inlets(pores=pn.pores(['left', 'right', 'top', 'bottom']))
mip.run()
# Generate phase and physics
water = op.phases.Water(network=pn)
phys = op.physics.Standard(network=pn, phase=water, geometry=geo)

# Create algorithm, set boundary conditions and run simulation
sf = op.algorithms.StokesFlow(network=pn, phase=water)
Pin, Pout = (200_000, 101_325)
sf.set_value_BC(pores=pn.pores('left'), values=Pin)
sf.set_value_BC(pores=pn.pores('right'), values=Pout)
op.algorithms.StokesFlow(network=pn, phase=water).run()
Q = sf.rate(pores=pn.pores('left'))
A = Ny*Nz*Lc**2
L = Nx*Lc
mu = water['pore.viscosity'].mean()
K = Q*mu*L/(A*(Pin-Pout))

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-77-99eb7690f599> in <module>
     25 sf.set_value_BC(pores=pn.pores('right'), values=Pout)
     26 op.algorithms.StokesFlow(network=pn, phase=water).run()
---> 27 Q = sf.rate(pores=pn.pores('left'))
     28 A = Ny*Nz*Lc**2
     29 L = Nx*Lc

~\anaconda3\lib\site-packages\openpnm\algorithms\GenericTransport.py in rate(self, pores, throats, mode)
    887         phase = self.project.phases()[self.settings['phase']]
    888         g = phase[self.settings['conductance']]
--> 889         quantity = self[self.settings['quantity']]
    890 
    891         P12 = network['throat.conns']

~\anaconda3\lib\site-packages\openpnm\core\Base.py in __getitem__(self, key)
    275             vals = super().__getitem__(key)
    276         else:
--> 277             raise KeyError(key)
    278         return vals
    279 

KeyError: 'pore.pressure'

I have tried to change code sf.set_value_BC(pores=pn.pores('left'), values=Pin) and
sf.rate(pores=pn.pores('left')) but still not work. Can you help me with that? Thank you so much!

[jgostick]

This is an easy one to fix :-) You have create a 'StokesFlow' object (sf) and added boundary conditions, BUT then when you attempt to run it, you are actually creating a second StokesFlow algorithm object: op.algorithms.StokesFlow(network=pn, phase=water).run() should just be sf.run().

[qingqi-code]

It works. Thank you so much!