Conduction in 1 D network.

[Umang-S93]

Hi,
I am trying to solve the convection and conduction in 1 D problem. it solves and produce irrelevant results. Has anyone tried this before ? At one end we are defined flux (h* T_inf-T0) and other end is adiabatic. Moreover , it takes huge amount of time. Results we have got it's on the power of 9 which is irrelevant. Please mention your comments , if anyone tried or know how it actually works.

import openpnm as op

net = op.network.Cubic(shape=[5 1, 1], spacing=0.001, 1, 1])

ax = op.visualization.plot_coordinates(net)
ax = op.visualization.plot_connections(net, ax=ax)

Add geometry models
net.add_model_collection(op.models.collections.geometry.spheres_and_cylinders)
net.regenerate_models()

phase = op.phase.Phase(network=net)

Assign material properties to the phase
phase['throat.thermal_conductivity'] = 0.2 # Thermal conductivity (W/mK)
phase['pore.density'] = 700 # Density (kg/m^3)
phase['pore.specific_heat'] = 500 # Specific heat capacity (J/kgK)

phase.add_model(propname='throat.thermal_conductance',
model=op.models.physics.thermal_conductance.series_resistors)

algorithm
sim = op.algorithms.TransientFourierConduction(network=net, phase=phase)

Set initial conditions
T_initial = 300 # K
phase['pore.temperature'] = T_initial

Set boundary conditions
T_external = 1173 # K
h = 200 # W/m²K

left_pores = net.pores('left')
right_pores = net.pores('right')

sim.set_rate_BC(pores=left_pores, rates=h * (T_external - T_initial), mode='overwrite')
sim.set_rate_BC(pores=right_pores, rates=0, mode='overwrite') # Adiabatic condition

Define time
tspan = np.linspace(x0= 300, tspan = [0,100])

for i in range(1, n_steps):
sim.run(x0=phase['pore.temperature'], tspan=[tspan[i-1], tspan[i]])
T_results[i, :] = sim['pore.temperature'] # Store results

Plot the results
plt.figure(figsize=(10, 6))
for i in range(N_pores):
plt.plot(tspan, T_results[:, i], label=f'Pore {i}')
plt.xlabel('Time (s)')
plt.ylabel('Temperature (K)')
plt.legend()
plt.title('Temperature Profiles in Porous Media')
plt.show()