def METHOD_NAME(self):
    f = op.models.physics.capillary_pressure.purcell
    self.water.add_model(
        propname="pore.capillary_pressure",
        model=f,
        r_toroid=0.1,
        surface_tension="pore.surface_tension",
        contact_angle="pore.contact_angle",
        diameter="pore.diameter",
    )
    self.water.regenerate_models()
    a = 0.2648436086476371
    assert_approx_equal(self.water["pore.capillary_pressure"][0], a)
    del self.water.models["pore.capillary_pressure"]