Exemplo n.º 1
0
def test_scaling(model3):
    m = model3
    metadata = m.fs.properties.get_metadata().properties

    for v_name in metadata:
        getattr(m.fs.stream[0], v_name)

    calculate_scaling_factors(m)

    # check that all variables have scaling factors
    unscaled_var_list = list(unscaled_variables_generator(m))
    [print(i) for i in unscaled_var_list]
    assert len(unscaled_var_list) == 0

    # check if any variables are badly scaled
    badly_scaled_var_list = list(badly_scaled_var_generator(m))
    assert len(badly_scaled_var_list) == 0

    # check that all constraints have been scaled
    unscaled_constraint_list = list(unscaled_constraints_generator(m))
    [print(i) for i in unscaled_constraint_list]

    assert len(unscaled_constraint_list) == 0

    # m.fs.stream[0].scaling_factor.display()
    for j in m.fs.properties.config.solute_list:
        assert get_scaling_factor(m.fs.stream[0].mw_comp[j]) is not None
        assert (get_scaling_factor(m.fs.stream[0].diffus_phase_comp["Liq", j])
                is not None)
        assert (get_scaling_factor(m.fs.stream[0].act_coeff_phase_comp["Liq",
                                                                       j])
                is not None)
    assert get_scaling_factor(
        m.fs.stream[0].dens_mass_phase["Liq"]) is not None
    assert get_scaling_factor(m.fs.stream[0].visc_d_phase["Liq"]) is not None
    def test_calculate_scaling(self, unit_frame):
        m = unit_frame

        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1,
                                            index=("Liq", "H2O"))
        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1e2,
                                            index=("Liq", "Na"))
        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1e4,
                                            index=("Liq", "Ca"))
        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1e3,
                                            index=("Liq", "Mg"))
        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1e3,
                                            index=("Liq", "SO4"))
        m.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                            1e2,
                                            index=("Liq", "Cl"))
        calculate_scaling_factors(m)

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0
Exemplo n.º 3
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def test_full_auto_scaling_mbtype_element():
    m = pyo.ConcreteModel()
    m.fs = FlowsheetBlock(default={"dynamic": True, "time_units": pyo.units.s})
    m.fs.pp = PhysicalParameterTestBlock()
    m.fs.rp = ReactionParameterTestBlock(default={"property_package": m.fs.pp})
    m.fs.cv = ControlVolume1DBlock(
        default={
            "property_package": m.fs.pp,
            "reaction_package": m.fs.rp,
            "transformation_method": "dae.finite_difference",
            "transformation_scheme": "BACKWARD",
            "finite_elements": 10
        })
    m.fs.cv.add_geometry()
    m.fs.cv.add_state_blocks(has_phase_equilibrium=False)
    m.fs.cv.add_reaction_blocks(has_equilibrium=False)

    m.fs.cv.add_total_element_balances(has_mass_transfer=True)

    m.fs.cv.apply_transformation()
    m.discretizer = pyo.TransformationFactory('dae.finite_difference')
    m.discretizer.apply_to(m, nfe=3, wrt=m.fs.time, scheme="BACKWARD")

    iscale.calculate_scaling_factors(m)

    # check that all variables have scaling factors
    unscaled_var_list = list(iscale.unscaled_variables_generator(m))
    assert len(unscaled_var_list) == 0
    # check that all constraints have been scaled
    unscaled_constraint_list = list(iscale.unscaled_constraints_generator(m))
    assert len(unscaled_constraint_list) == 0
Exemplo n.º 4
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    def test_default_scaling(self, coag_obj_fail):
        model = coag_obj_fail

        model.fs.stream = model.fs.properties.build_state_block([0],
                                                                default={})

        # call scaling without setting defaults
        iscale.calculate_scaling_factors(model.fs)

        # check that all variables have scaling factors
        unscaled_var_list = list(iscale.unscaled_variables_generator(model))
        assert len(unscaled_var_list) == 0

        # check that all constraints have been scaled
        unscaled_constraint_list = list(
            iscale.unscaled_constraints_generator(model))
        assert len(unscaled_constraint_list) == 0

        # check if any variables are badly scaled
        badly_scaled_var_values = {
            var.name: val
            for (var, val) in iscale.badly_scaled_var_generator(
                model, large=1e2, small=1e-2)
        }
        assert not badly_scaled_var_values
Exemplo n.º 5
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    def test_scaling(self, coag_obj):
        model = coag_obj

        # Set some scaling factors and look for 'bad' scaling
        model.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                                1,
                                                index=("Liq", "H2O"))
        model.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                                1e2,
                                                index=("Liq", "TSS"))
        model.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                                1e2,
                                                index=("Liq", "TDS"))
        model.fs.properties.set_default_scaling("flow_mass_phase_comp",
                                                1e3,
                                                index=("Liq", "Sludge"))
        iscale.calculate_scaling_factors(model.fs)

        # check that all variables have scaling factors
        unscaled_var_list = list(iscale.unscaled_variables_generator(model))
        assert len(unscaled_var_list) == 0

        # check that all constraints have been scaled
        unscaled_constraint_list = list(
            iscale.unscaled_constraints_generator(model))
        assert len(unscaled_constraint_list) == 0

        # check if any variables are badly scaled
        badly_scaled_var_values = {
            var.name: val
            for (var, val) in iscale.badly_scaled_var_generator(
                model, large=1e2, small=1e-2)
        }
        assert not badly_scaled_var_values
Exemplo n.º 6
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    def test_calculate_scaling(self, unit_frame):
        m = unit_frame

        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1,
                                            index=('Liq', 'H2O'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e2,
                                            index=('Liq', 'Na'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e4,
                                            index=('Liq', 'Ca'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e3,
                                            index=('Liq', 'Mg'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e3,
                                            index=('Liq', 'SO4'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e2,
                                            index=('Liq', 'Cl'))
        calculate_scaling_factors(m)

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0
Exemplo n.º 7
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    def test_calculate_scaling(self, NF_frame):
        m = NF_frame
        calculate_scaling_factors(m)

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0
Exemplo n.º 8
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    def test_calculate_scaling(self, unit_frame):
        m = unit_frame
        calculate_scaling_factors(m)

        # check that all variables have scaling factors
        unscaled_var_list = list(
            unscaled_variables_generator(m.fs.unit, include_fixed=True))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0
Exemplo n.º 9
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def test_full_auto_scaling_dynamic():
    m = pyo.ConcreteModel()
    m.fs = FlowsheetBlock(default={"dynamic": True, "time_units": pyo.units.s})
    m.fs.pp = PhysicalParameterTestBlock()
    m.fs.rp = ReactionParameterTestBlock(default={"property_package": m.fs.pp})
    m.fs.cv = ControlVolume1DBlock(
        default={
            "property_package": m.fs.pp,
            "reaction_package": m.fs.rp,
            "transformation_method": "dae.finite_difference",
            "transformation_scheme": "BACKWARD",
            "finite_elements": 10
        })
    m.fs.cv.add_geometry()
    m.fs.cv.add_state_blocks(has_phase_equilibrium=True)
    m.fs.cv.add_reaction_blocks(has_equilibrium=True)

    m.fs.cv.add_material_balances(
        balance_type=MaterialBalanceType.componentTotal,
        has_rate_reactions=True,
        has_equilibrium_reactions=True,
        has_phase_equilibrium=True,
        has_mass_transfer=True)

    m.fs.cv.add_energy_balances(balance_type=EnergyBalanceType.enthalpyTotal,
                                has_heat_of_reaction=True,
                                has_heat_transfer=True,
                                has_work_transfer=True,
                                has_enthalpy_transfer=True)

    m.fs.cv.add_momentum_balances(
        balance_type=MomentumBalanceType.pressureTotal,
        has_pressure_change=True)

    m.fs.cv.apply_transformation()
    m.discretizer = pyo.TransformationFactory('dae.finite_difference')
    m.discretizer.apply_to(m, nfe=3, wrt=m.fs.time, scheme="BACKWARD")

    iscale.calculate_scaling_factors(m)

    # check that all variables have scaling factors
    unscaled_var_list = list(iscale.unscaled_variables_generator(m))
    # Unscaled variables are:
    # rate_reaction_extent (2 reactions, 44 time & space points)
    # equilibrium_reaction_extent  (2 reactions, 44 time & space points)
    assert len(unscaled_var_list) == 176
    # check that all constraints have been scaled
    unscaled_constraint_list = list(iscale.unscaled_constraints_generator(m))
    assert len(unscaled_constraint_list) == 0
Exemplo n.º 10
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    def test_scaling(self, frame):
        m = frame

        set_scaling_factor(m.fs.stream[0].flow_mass_phase_comp['Liq', 'H2O'], 1)
        set_scaling_factor(m.fs.stream[0].flow_mass_phase_comp['Liq', 'TDS'], 1e2)
        calculate_scaling_factors(m.fs)

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0

        # check if any variables are badly scaled
        badly_scaled_var_list = list(badly_scaled_var_generator(m))
        assert len(badly_scaled_var_list) == 0
def test_full_auto_scaling():
    m = pyo.ConcreteModel()
    m.fs = FlowsheetBlock(default={"dynamic": False})
    m.fs.pp = PhysicalParameterTestBlock()
    m.fs.rp = ReactionParameterTestBlock(default={"property_package": m.fs.pp})
    m.fs.cv = ControlVolume0DBlock(default={
        "property_package": m.fs.pp,
        "reaction_package": m.fs.rp})
    m.fs.cv.add_geometry()
    m.fs.cv.add_state_blocks(has_phase_equilibrium=True)
    m.fs.cv.add_reaction_blocks(has_equilibrium=True)

    m.fs.cv.add_material_balances(
        balance_type=MaterialBalanceType.componentTotal,
        has_rate_reactions=True,
        has_equilibrium_reactions=True,
        has_phase_equilibrium=True,
        has_mass_transfer=True)

    m.fs.cv.add_energy_balances(
        balance_type=EnergyBalanceType.enthalpyTotal,
        has_heat_of_reaction=True,
        has_heat_transfer=True,
        has_work_transfer=True,
        has_enthalpy_transfer=True)

    m.fs.cv.add_momentum_balances(
        balance_type=MomentumBalanceType.pressureTotal,
        has_pressure_change=True)

    iscale.calculate_scaling_factors(m)

    # check that all variables have scaling factors
    unscaled_var_list = list(iscale.unscaled_variables_generator(m))
    # Unscaled variables are:
    # rate_reaction_extent (2 reactions)
    # equilibrium_reaction_extent  (2 reactions)
    assert len(unscaled_var_list) == 4
    # check that all constraints have been scaled
    unscaled_constraint_list = list(iscale.unscaled_constraints_generator(m))
    assert len(unscaled_constraint_list) == 0
Exemplo n.º 12
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    def test_calculate_scaling(self, Pump_frame):
        m = Pump_frame

        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1,
                                            index=('Liq', 'H2O'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e2,
                                            index=('Liq', 'TDS'))
        calculate_scaling_factors(m)

        if get_scaling_factor(
                m.fs.unit.ratioP
        ) is None:  # if IDAES hasn't specified a scaling factor
            set_scaling_factor(m.fs.unit.ratioP, 1)

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m))
        assert len(unscaled_var_list) == 0
        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0
Exemplo n.º 13
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    def test_scaling(self, frame_stateblock):
        m = frame_stateblock
        calculate_scaling_factors(m.fs.stream[0])

        # check that all variables have scaling factors
        unscaled_var_list = list(unscaled_variables_generator(m.fs.stream[0]))
        if len(unscaled_var_list) != 0:
            unscaled_var_name_list = [v.name for v in unscaled_var_list]
            raise PropertyAttributeError(
                "The following variable(s) are unscaled: {lst}".format(
                    lst=unscaled_var_name_list))

        # check that all constraints have been scaled
        unscaled_constraint_list = list(
            unscaled_constraints_generator(m.fs.stream[0]))
        if len(unscaled_constraint_list) != 0:
            unscaled_constraint_name_list = [
                c.name for c in unscaled_constraint_list
            ]
            raise PropertyAttributeError(
                "The following constraint(s) are unscaled: {lst}".format(
                    lst=unscaled_constraint_name_list))
Exemplo n.º 14
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def test_find_unscaled_vars_and_constraints():
    m = pyo.ConcreteModel()
    m.b = pyo.Block()
    m.x = pyo.Var(initialize=1e6)
    m.y = pyo.Var(initialize=1e-8)
    m.z = pyo.Var(initialize=1e-20)
    m.c1 = pyo.Constraint(expr=m.x == 0)
    m.c2 = pyo.Constraint(expr=m.y == 0)
    m.b.w = pyo.Var([1, 2, 3], initialize=1e10)
    m.b.c1 = pyo.Constraint(expr=m.b.w[1] == 0)
    m.b.c2 = pyo.Constraint(expr=m.b.w[2] == 0)
    m.c3 = pyo.Constraint(expr=m.z == 0)

    sc.set_scaling_factor(m.x, 1)
    sc.set_scaling_factor(m.b.w[1], 2)
    sc.set_scaling_factor(m.c1, 1)
    sc.set_scaling_factor(m.b.c1, 1)
    sc.constraint_scaling_transform(m.c3, 1)

    a = [id(v) for v in sc.unscaled_variables_generator(m)]
    # Make sure we pick up the right variales
    assert id(m.x) not in a
    assert id(m.y) in a
    assert id(m.z) in a
    assert id(m.b.w[1]) not in a
    assert id(m.b.w[2]) in a
    assert id(m.b.w[3]) in a
    assert len(a) == 4  #make sure we didn't pick up any other random stuff

    a = [id(v) for v in sc.unscaled_constraints_generator(m)]
    assert id(m.c1) not in a
    assert id(m.b.c1) not in a
    assert id(m.c2) in a
    assert id(m.b.c2) in a
    assert id(m.c3) not in a
    assert len(a) == 2  #make sure we didn't pick up any other random stuff
Exemplo n.º 15
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    def test_Pdrop_fixed_per_unit_length(self):
        """ Testing 0D-RO with PressureChangeType.fixed_per_unit_length option.
        """
        m = ConcreteModel()
        m.fs = FlowsheetBlock(default={"dynamic": False})

        m.fs.properties = props.NaClParameterBlock()

        m.fs.unit = ReverseOsmosis0D(
            default={
                "property_package": m.fs.properties,
                "has_pressure_change": True,
                "concentration_polarization_type":
                ConcentrationPolarizationType.calculated,
                "mass_transfer_coefficient":
                MassTransferCoefficient.calculated,
                "pressure_change_type":
                PressureChangeType.fixed_per_unit_length
            })

        # fully specify system
        feed_flow_mass = 1
        feed_mass_frac_NaCl = 0.035
        feed_mass_frac_H2O = 1 - feed_mass_frac_NaCl
        feed_pressure = 50e5
        feed_temperature = 273.15 + 25
        membrane_area = 50
        length = 20
        A = 4.2e-12
        B = 3.5e-8
        pressure_atmospheric = 101325
        membrane_pressure_drop = 3e5

        m.fs.unit.inlet.flow_mass_phase_comp[0, 'Liq', 'NaCl'].fix(
            feed_flow_mass * feed_mass_frac_NaCl)
        m.fs.unit.inlet.flow_mass_phase_comp[0, 'Liq', 'H2O'].fix(
            feed_flow_mass * feed_mass_frac_H2O)
        m.fs.unit.inlet.pressure[0].fix(feed_pressure)
        m.fs.unit.inlet.temperature[0].fix(feed_temperature)
        m.fs.unit.area.fix(membrane_area)
        m.fs.unit.A_comp.fix(A)
        m.fs.unit.B_comp.fix(B)
        m.fs.unit.permeate.pressure[0].fix(pressure_atmospheric)

        m.fs.unit.channel_height.fix(0.002)
        m.fs.unit.spacer_porosity.fix(0.75)
        m.fs.unit.length.fix(length)
        m.fs.unit.dP_dx.fix(-membrane_pressure_drop / length)

        # test statistics
        assert number_variables(m) == 110
        assert number_total_constraints(m) == 80
        assert number_unused_variables(m) == 0

        # test degrees of freedom
        assert degrees_of_freedom(m) == 0

        # test scaling
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1,
                                            index=('Liq', 'H2O'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e2,
                                            index=('Liq', 'NaCl'))

        calculate_scaling_factors(m)

        # check that all variables have scaling factors.
        # TODO: see aforementioned TODO on revisiting scaling and associated testing for property models.
        unscaled_var_list = list(
            unscaled_variables_generator(m.fs.unit, include_fixed=True))
        assert len(unscaled_var_list) == 0

        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0

        # test initialization
        initialization_tester(m)

        # test variable scaling
        badly_scaled_var_lst = list(badly_scaled_var_generator(m))
        assert badly_scaled_var_lst == []

        # test solve
        solver.options = {'nlp_scaling_method': 'user-scaling'}
        results = solver.solve(m, tee=True)

        # Check for optimal solution
        assert results.solver.termination_condition == \
               TerminationCondition.optimal
        assert results.solver.status == SolverStatus.ok

        # test solution
        assert (pytest.approx(-3.000e5,
                              rel=1e-3) == value(m.fs.unit.deltaP[0]))
        assert (pytest.approx(2.205e-3, rel=1e-3) == value(
            m.fs.unit.flux_mass_phase_comp_avg[0, 'Liq', 'H2O']))
        assert (pytest.approx(1.826e-6, rel=1e-3) == value(
            m.fs.unit.flux_mass_phase_comp_avg[0, 'Liq', 'NaCl']))
        assert (pytest.approx(0.1103, rel=1e-3) == value(
            m.fs.unit.properties_permeate[0].flow_mass_phase_comp['Liq',
                                                                  'H2O']))
        assert (pytest.approx(9.129e-5, rel=1e-3) == value(
            m.fs.unit.properties_permeate[0].flow_mass_phase_comp['Liq',
                                                                  'NaCl']))
        assert (pytest.approx(35.751, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_in[0].conc_mass_phase_comp['Liq',
                                                                      'NaCl']))
        assert (pytest.approx(53.506, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_interface_in[0].
            conc_mass_phase_comp['Liq', 'NaCl']))
        assert (pytest.approx(40.207, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_out[0].conc_mass_phase_comp['Liq',
                                                                       'NaCl'])
                )
        assert (pytest.approx(52.476, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_interface_out[0].
            conc_mass_phase_comp['Liq', 'NaCl']))
Exemplo n.º 16
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        "H2O":0.0,
        "CO2":0.0034,
        "N2":0.0361,
        "Ar":0.0,
        "SO2":0.0}

    m, solver = main(
        comps=comps,
        rxns=rxns,
        phases=phases,
        air_comp=air_comp,
        ng_comp=ng_comp)
    run_full_load(m, solver)
    #iscale.constraint_autoscale_large_jac(m)
    jac, nlp = iscale.get_jacobian(m, scaled=True)
    print("Extreme Jacobian entries:")
    for i in iscale.extreme_jacobian_entries(jac=jac, nlp=nlp, large=100):
        print(f"    {i[0]:.2e}, [{i[1]}, {i[2]}]")
    print("Unscaled constraints:")
    for c in iscale.unscaled_constraints_generator(m):
        print(f"    {c}")
    print("Scaled constraints by factor:")
    for c, s in iscale.constraints_with_scale_factor_generator(m):
        print(f"    {c}, {s}")
    print("Badly scaled variables:")
    for v, sv in iscale.badly_scaled_var_generator(m, large=1e2, small=1e-2, zero=1e-12):
        print(f"    {v} -- {sv} -- {iscale.get_scaling_factor(v)}")
    print(f"Jacobian Condition Number: {iscale.jacobian_cond(jac=jac):.2e}")
    write_pfd_results("gas_turbine_results.svg", m.tags, m.tag_format)
    #run_series(m, solver)
Exemplo n.º 17
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    def test_CP_calculation_with_kf_fixed(self):
        """ Testing 0D-RO with ConcentrationPolarizationType.calculated option enabled.
        This option makes use of an alternative constraint for the feed-side, membrane-interface concentration.
        Additionally, two more variables are created when this option is enabled: Kf_io - feed-channel
        mass transfer coefficients at the channel inlet and outlet.
        """
        m = ConcreteModel()
        m.fs = FlowsheetBlock(default={"dynamic": False})

        m.fs.properties = props.NaClParameterBlock()

        m.fs.unit = ReverseOsmosis0D(
            default={
                "property_package": m.fs.properties,
                "has_pressure_change": True,
                "concentration_polarization_type":
                ConcentrationPolarizationType.calculated,
                "mass_transfer_coefficient": MassTransferCoefficient.fixed
            })

        # fully specify system
        feed_flow_mass = 1
        feed_mass_frac_NaCl = 0.035
        feed_pressure = 50e5
        feed_temperature = 273.15 + 25
        membrane_pressure_drop = 3e5
        membrane_area = 50
        A = 4.2e-12
        B = 3.5e-8
        pressure_atmospheric = 101325
        kf = 2e-5

        feed_mass_frac_H2O = 1 - feed_mass_frac_NaCl
        m.fs.unit.inlet.flow_mass_phase_comp[0, 'Liq', 'NaCl'].fix(
            feed_flow_mass * feed_mass_frac_NaCl)
        m.fs.unit.inlet.flow_mass_phase_comp[0, 'Liq', 'H2O'].fix(
            feed_flow_mass * feed_mass_frac_H2O)
        m.fs.unit.inlet.pressure[0].fix(feed_pressure)
        m.fs.unit.inlet.temperature[0].fix(feed_temperature)
        m.fs.unit.deltaP.fix(-membrane_pressure_drop)
        m.fs.unit.area.fix(membrane_area)
        m.fs.unit.A_comp.fix(A)
        m.fs.unit.B_comp.fix(B)
        m.fs.unit.permeate.pressure[0].fix(pressure_atmospheric)
        m.fs.unit.Kf_io[0, 'in', 'NaCl'].fix(kf)
        m.fs.unit.Kf_io[0, 'out', 'NaCl'].fix(kf)

        # test statistics
        assert number_variables(m) == 94
        assert number_total_constraints(m) == 65
        assert number_unused_variables(
            m) == 7  # vars from property package parameters

        # test degrees of freedom
        assert degrees_of_freedom(m) == 0

        # test scaling
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1,
                                            index=('Liq', 'H2O'))
        m.fs.properties.set_default_scaling('flow_mass_phase_comp',
                                            1e2,
                                            index=('Liq', 'NaCl'))
        calculate_scaling_factors(m)

        # check that all variables have scaling factors.
        # TODO: Setting the "include_fixed" arg as True reveals
        #  unscaled vars that weren't being accounted for previously. However, calling the whole block (i.e.,
        #  m) shows that several NaCl property parameters are unscaled. For now, we are just interested in ensuring
        #  unit variables are scaled (hence, calling m.fs.unit) but might need to revisit scaling and associated
        #  testing for property models.

        unscaled_var_list = list(
            unscaled_variables_generator(m.fs.unit, include_fixed=True))
        assert len(unscaled_var_list) == 0

        # check that all constraints have been scaled
        unscaled_constraint_list = list(unscaled_constraints_generator(m))
        assert len(unscaled_constraint_list) == 0

        # test initialization
        initialization_tester(m)

        # test variable scaling
        badly_scaled_var_lst = list(badly_scaled_var_generator(m))
        assert badly_scaled_var_lst == []

        # test solve
        solver.options = {'nlp_scaling_method': 'user-scaling'}
        results = solver.solve(m)

        # Check for optimal solution
        assert results.solver.termination_condition == \
               TerminationCondition.optimal
        assert results.solver.status == SolverStatus.ok

        # test solution
        assert (pytest.approx(3.807e-3, rel=1e-3) == value(
            m.fs.unit.flux_mass_phase_comp_avg[0, 'Liq', 'H2O']))
        assert (pytest.approx(1.668e-6, rel=1e-3) == value(
            m.fs.unit.flux_mass_phase_comp_avg[0, 'Liq', 'NaCl']))
        assert (pytest.approx(0.1904, rel=1e-3) == value(
            m.fs.unit.properties_permeate[0].flow_mass_phase_comp['Liq',
                                                                  'H2O']))
        assert (pytest.approx(8.342e-5, rel=1e-3) == value(
            m.fs.unit.properties_permeate[0].flow_mass_phase_comp['Liq',
                                                                  'NaCl']))
        assert (pytest.approx(35.751, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_in[0].conc_mass_phase_comp['Liq',
                                                                      'NaCl']))
        assert (pytest.approx(46.123, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_interface_in[0].
            conc_mass_phase_comp['Liq', 'NaCl']))
        assert (pytest.approx(44.321, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_out[0].conc_mass_phase_comp['Liq',
                                                                       'NaCl'])
                )
        assert (pytest.approx(50.081, rel=1e-3) == value(
            m.fs.unit.feed_side.properties_interface_out[0].
            conc_mass_phase_comp['Liq', 'NaCl']))