def iapws_underwood(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"delta_temperature_callback":
delta_temperature_underwood_callback,
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
m.fs.unit.inlet_1.flow_mol[0].fix(100)
m.fs.unit.inlet_1.enth_mol[0].fix(4000)
m.fs.unit.inlet_1.pressure[0].fix(101325)
m.fs.unit.inlet_2.flow_mol[0].fix(100)
m.fs.unit.inlet_2.enth_mol[0].fix(3500)
m.fs.unit.inlet_2.pressure[0].fix(101325)
m.fs.unit.area.fix(1000)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
return m
def btx(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = BTXParameterBlock(default={"valid_phase": 'Liq'})
m.fs.unit = HeatExchanger(default={
"hot_side_name":"hot",
"cold_side_name":"cold",
"hot": {"property_package": m.fs.properties},
"cold": {"property_package": m.fs.properties},
"flow_pattern": HeatExchangerFlowPattern.cocurrent})
m.fs.unit.hot_inlet.flow_mol[0].fix(5) # mol/s
m.fs.unit.hot_inlet.temperature[0].fix(365) # K
m.fs.unit.hot_inlet.pressure[0].fix(101325) # Pa
m.fs.unit.hot_inlet.mole_frac_comp[0, "benzene"].fix(0.5)
m.fs.unit.hot_inlet.mole_frac_comp[0, "toluene"].fix(0.5)
m.fs.unit.cold_inlet.flow_mol[0].fix(1) # mol/s
m.fs.unit.cold_inlet.temperature[0].fix(300) # K
m.fs.unit.cold_inlet.pressure[0].fix(101325) # Pa
m.fs.unit.cold_inlet.mole_frac_comp[0, "benzene"].fix(0.5)
m.fs.unit.cold_inlet.mole_frac_comp[0, "toluene"].fix(0.5)
m.fs.unit.area.fix(1)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
return m
def basic_model(cb=delta_temperature_lmtd_callback):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.unit = HeatExchanger(default={
"shell": {"property_package": m.fs.properties},
"tube": {"property_package": m.fs.properties},
"delta_temperature_callback": cb,
"flow_pattern": HeatExchangerFlowPattern.countercurrent})
# Set inputs
m.fs.unit.inlet_1.flow_mol[0].fix(100)
m.fs.unit.inlet_1.enth_mol[0].fix(4000)
m.fs.unit.inlet_1.pressure[0].fix(101325)
m.fs.unit.inlet_2.flow_mol[0].fix(100)
m.fs.unit.inlet_2.enth_mol[0].fix(3500)
m.fs.unit.inlet_2.pressure[0].fix(101325)
m.fs.unit.area.fix(1000)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
assert degrees_of_freedom(m) == 0
m.fs.unit.get_costing()
m.fs.unit.initialize()
return m
def sapon(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = SaponificationParameterBlock()
m.fs.unit = HeatExchanger(default={
"shell": {"property_package": m.fs.properties},
"tube": {"property_package": m.fs.properties},
"flow_pattern": HeatExchangerFlowPattern.crossflow})
m.fs.unit.inlet_1.flow_vol[0].fix(1e-3)
m.fs.unit.inlet_1.temperature[0].fix(320)
m.fs.unit.inlet_1.pressure[0].fix(101325)
m.fs.unit.inlet_1.conc_mol_comp[0, "H2O"].fix(55388.0)
m.fs.unit.inlet_1.conc_mol_comp[0, "NaOH"].fix(100.0)
m.fs.unit.inlet_1.conc_mol_comp[0, "EthylAcetate"].fix(100.0)
m.fs.unit.inlet_1.conc_mol_comp[0, "SodiumAcetate"].fix(0.0)
m.fs.unit.inlet_1.conc_mol_comp[0, "Ethanol"].fix(0.0)
m.fs.unit.inlet_2.flow_vol[0].fix(1e-3)
m.fs.unit.inlet_2.temperature[0].fix(300)
m.fs.unit.inlet_2.pressure[0].fix(101325)
m.fs.unit.inlet_2.conc_mol_comp[0, "H2O"].fix(55388.0)
m.fs.unit.inlet_2.conc_mol_comp[0, "NaOH"].fix(100.0)
m.fs.unit.inlet_2.conc_mol_comp[0, "EthylAcetate"].fix(100.0)
m.fs.unit.inlet_2.conc_mol_comp[0, "SodiumAcetate"].fix(0.0)
m.fs.unit.inlet_2.conc_mol_comp[0, "Ethanol"].fix(0.0)
m.fs.unit.area.fix(1000)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
m.fs.unit.crossflow_factor.fix(0.6)
return m
def test_discharge():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.steam_prop = Iapws95ParameterBlock()
m.fs.therminol66_prop = ThermalOilParameterBlock()
m.fs.discharge_hx = HeatExchanger(
default={
"hot_side_name": "tube",
"cold_side_name": "shell",
"tube": {
"property_package": m.fs.therminol66_prop
},
"shell": {
"property_package": m.fs.steam_prop
},
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
# Set inputs
# Steam
m.fs.discharge_hx.inlet_2.flow_mol[0].fix(4163)
m.fs.discharge_hx.inlet_2.pressure[0].fix(1.379e+6)
m.fs.discharge_hx.inlet_2.enth_mol[0].fix(
htpx(T=300.15 * units.K, P=1.379e+6 * units.Pa))
# Thermal Oil
m.fs.discharge_hx.inlet_1.flow_mass[0].fix(833.3)
m.fs.discharge_hx.inlet_1.temperature[0].fix(256 + 273.15)
m.fs.discharge_hx.inlet_1.pressure[0].fix(101325)
# Designate the Area
m.fs.discharge_hx.area.fix(12180)
m.fs.discharge_hx.overall_heat_transfer_coefficient.fix(432.677)
# Designate the U Value.
m.fs.discharge_hx.initialize()
m.fs.discharge_hx.heat_duty.fix(1.066e+08)
m.fs.discharge_hx.area.unfix()
solver = get_solver()
results = solver.solve(m, tee=False)
# Check for optimal solution
assert results.solver.termination_condition == \
TerminationCondition.optimal
assert results.solver.status == SolverStatus.ok
# Tests to make sure the discharge cycle is functioning properly.
assert value(m.fs.discharge_hx.outlet_1.temperature[0]) == \
pytest.approx(473.5, rel=1e-1)
assert value(m.fs.discharge_hx.outlet_2.enth_mol[0]) == \
pytest.approx(27668.5, rel=1e-1)
def test_charge():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.steam_prop = Iapws95ParameterBlock()
m.fs.therminol66_prop = ThermalOilParameterBlock()
m.fs.charge_hx = HeatExchanger(
default={
"shell": {
"property_package": m.fs.steam_prop
},
"tube": {
"property_package": m.fs.therminol66_prop
},
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
# Set inputs
# Steam
m.fs.charge_hx.inlet_1.flow_mol[0].fix(4163)
m.fs.charge_hx.inlet_1.enth_mol[0].fix(
htpx(T=573.15 * units.K, P=5.0e+6 * units.Pa))
m.fs.charge_hx.inlet_1.pressure[0].fix(5.0e+6)
# Thermal Oil
m.fs.charge_hx.inlet_2.flow_mass[0].fix(833.3)
m.fs.charge_hx.inlet_2.temperature[0].fix(200 + 273.15)
m.fs.charge_hx.inlet_2.pressure[0].fix(101325)
m.fs.charge_hx.area.fix(12180)
m.fs.charge_hx.overall_heat_transfer_coefficient.fix(432.677)
m.fs.charge_hx.initialize()
m.fs.charge_hx.heat_duty.fix(1.066e+08)
# Needed to make the system solve.
m.fs.charge_hx.overall_heat_transfer_coefficient.unfix()
solver = get_solver()
results = solver.solve(m)
# Check for optimal solution
assert results.solver.termination_condition == \
TerminationCondition.optimal
assert results.solver.status == SolverStatus.ok
# Testing the exit values of the heat exchanger.
assert value(m.fs.charge_hx.outlet_2.temperature[0]) == \
pytest.approx(528.83, rel=1e-1)
assert value(m.fs.charge_hx.outlet_1.enth_mol[0]) == \
pytest.approx(27100.28, rel=1e-1)
def test_config():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = PhysicalParameterTestBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
}
})
# Check unit config arguments
# There are 8 to 10 arguments since you can add a side 1 and 2 config by
# side_1, side_2, or whatever the user named them
assert len(m.fs.unit.config) >= 8 and len(m.fs.unit.config) <= 10
assert not m.fs.unit.config.dynamic
assert not m.fs.unit.config.has_holdup
assert isinstance(m.fs.unit.config.shell, ConfigBlock)
assert isinstance(m.fs.unit.config.tube, ConfigBlock)
assert m.fs.unit.config.delta_temperature_callback is \
delta_temperature_lmtd_callback
assert m.fs.unit.config.flow_pattern == \
HeatExchangerFlowPattern.countercurrent
# Check shell config
assert len(m.fs.unit.config.shell) == 7
assert m.fs.unit.config.shell.material_balance_type == \
MaterialBalanceType.useDefault
assert m.fs.unit.config.shell.energy_balance_type == \
EnergyBalanceType.useDefault
assert m.fs.unit.config.shell.momentum_balance_type == \
MomentumBalanceType.pressureTotal
assert not m.fs.unit.config.shell.has_phase_equilibrium
assert not m.fs.unit.config.shell.has_pressure_change
assert m.fs.unit.config.shell.property_package is m.fs.properties
# Check tube config
assert len(m.fs.unit.config.tube) == 7
assert m.fs.unit.config.tube.material_balance_type == \
MaterialBalanceType.useDefault
assert m.fs.unit.config.tube.energy_balance_type == \
EnergyBalanceType.useDefault
assert m.fs.unit.config.tube.momentum_balance_type == \
MomentumBalanceType.pressureTotal
assert not m.fs.unit.config.tube.has_phase_equilibrium
assert not m.fs.unit.config.tube.has_pressure_change
assert m.fs.unit.config.tube.property_package is m.fs.properties
def test_costing():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
# Set inputs
m.fs.unit.inlet_1.flow_mol[0].fix(100)
m.fs.unit.inlet_1.enth_mol[0].fix(4000)
m.fs.unit.inlet_1.pressure[0].fix(101325)
m.fs.unit.inlet_2.flow_mol[0].fix(100)
m.fs.unit.inlet_2.enth_mol[0].fix(3500)
m.fs.unit.inlet_2.pressure[0].fix(101325)
m.fs.unit.area.fix(1000)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
assert degrees_of_freedom(m) == 0
m.fs.unit.initialize()
m.fs.unit.get_costing()
calculate_variable_from_constraint(m.fs.unit.costing.base_cost,
m.fs.unit.costing.base_cost_eq)
calculate_variable_from_constraint(m.fs.unit.costing.purchase_cost,
m.fs.unit.costing.cp_cost_eq)
assert_units_consistent(m.fs.unit.costing)
results = solver.solve(m)
# Check for optimal solution
assert results.solver.termination_condition == TerminationCondition.optimal
assert results.solver.status == SolverStatus.ok
assert m.fs.unit.costing.purchase_cost.value == \
pytest.approx(529738.6793, 1e-5)
def btx(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = BTXParameterBlock(default={"valid_phase": 'Liq'})
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"flow_pattern": HeatExchangerFlowPattern.cocurrent
})
return m
def sapon(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = SaponificationParameterBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"flow_pattern": HeatExchangerFlowPattern.crossflow
})
return m
def iapws(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
return m
def test_costing_book():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.unit = HeatExchanger(
default={
"shell": {
"property_package": m.fs.properties
},
"tube": {
"property_package": m.fs.properties
},
"flow_pattern": HeatExchangerFlowPattern.countercurrent
})
# Set inputs
m.fs.unit.inlet_1.flow_mol[0].fix(100)
m.fs.unit.inlet_1.enth_mol[0].fix(4000)
m.fs.unit.inlet_1.pressure[0].fix(101325)
m.fs.unit.inlet_2.flow_mol[0].fix(100)
m.fs.unit.inlet_2.enth_mol[0].fix(3500)
m.fs.unit.inlet_2.pressure[0].fix(101325)
m.fs.unit.area.fix(1000)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
# costing
m.fs.unit.get_costing(hx_type='floating_head',
length_factor='20ft',
year='2018')
m.fs.unit.area.fix(669.738) # m2
m.fs.unit.costing.pressure_factor.fix(1.19)
m.fs.unit.costing.material_factor.fix(4.05)
m.fs.costing.CE_index = 550
m.fs.unit.costing.hx_os = 1.0
calculate_variable_from_constraint(m.fs.unit.costing.base_cost_per_unit,
m.fs.unit.costing.base_cost_per_unit_eq)
calculate_variable_from_constraint(m.fs.unit.costing.purchase_cost,
m.fs.unit.costing.cp_cost_eq)
assert value(m.fs.unit.costing.base_cost) == \
pytest.approx(78802.0518, 1e-5)
assert m.fs.unit.costing.purchase_cost.value == \
pytest.approx(417765.1377, 1e-5)
def test_same_name():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
with pytest.raises(NameError):
m.fs.unit = HeatExchanger(default={"cold_side_name": "shell"})
HeatExchangerFlowPattern)
from idaes.core.util.model_statistics import degrees_of_freedom
# Import steam property package
from idaes.generic_models.properties.iapws95 import htpx, Iapws95ParameterBlock
from thermal_oil import ThermalOilParameterBlock
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.steam_prop = Iapws95ParameterBlock()
m.fs.therminol66_prop = ThermalOilParameterBlock()
m.fs.discharge_hx = HeatExchanger(
default={"hot_side_name": "tube", "cold_side_name": "shell",
"tube": {"property_package": m.fs.therminol66_prop},
"shell": {"property_package": m.fs.steam_prop},
"flow_pattern": HeatExchangerFlowPattern.countercurrent})
# Set inputs
#Steam
m.fs.discharge_hx.inlet_2.flow_mol[0].fix(4163)
m.fs.discharge_hx.inlet_2.pressure[0].fix(1.379e+6)
m.fs.discharge_hx.inlet_2.enth_mol[0].fix(htpx(T=300.15*units.K,
P=1.379e+6*units.Pa))
#Thermal Oil
m.fs.discharge_hx.inlet_1.flow_mass[0].fix(833.3)
m.fs.discharge_hx.inlet_1.temperature[0].fix(256 + 273.15)
m.fs.discharge_hx.inlet_1.pressure[0].fix(101325)
HeatExchangerFlowPattern)
# Import steam property package
from idaes.generic_models.properties.iapws95 import htpx, Iapws95ParameterBlock
from thermal_oil import ThermalOilParameterBlock
from idaes.core.util.model_statistics import degrees_of_freedom
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.steam_prop = Iapws95ParameterBlock()
m.fs.therminol66_prop = ThermalOilParameterBlock()
m.fs.charge_hx = HeatExchanger(
default={"shell": {"property_package": m.fs.steam_prop},
"tube": {"property_package": m.fs.therminol66_prop},
"flow_pattern": HeatExchangerFlowPattern.countercurrent})
# Set inputs
#Steam
m.fs.charge_hx.inlet_1.flow_mol[0].fix(4163)
m.fs.charge_hx.inlet_1.enth_mol[0].fix(htpx(T=573.15*units.K,
P=5.0e+6*units.Pa))
m.fs.charge_hx.inlet_1.pressure[0].fix(5.0e+6)
#Thermal Oil
m.fs.charge_hx.inlet_2.flow_mass[0].fix(833.3)
m.fs.charge_hx.inlet_2.temperature[0].fix(200 + 273.15)
m.fs.charge_hx.inlet_2.pressure[0].fix(101325)
m.fs.charge_hx.area.fix(12180)
def test_bad_option():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
with pytest.raises(KeyError):
m.fs.unit = HeatExchanger(default={"I'm a bad option": "hot"})
def test_heat_exchanger():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = props.SeawaterParameterBlock()
m.fs.unit = HeatExchanger(
default={
"hot_side_name": "hot",
"cold_side_name": "cold",
"hot": {
"property_package": m.fs.properties
},
"cold": {
"property_package": m.fs.properties
},
"delta_temperature_callback": delta_temperature_chen_callback,
"flow_pattern": HeatExchangerFlowPattern.countercurrent,
})
# 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", "TDS"))
iscale.set_scaling_factor(m.fs.unit.hot.heat, 1e-3)
iscale.set_scaling_factor(m.fs.unit.cold.heat, 1e-3)
iscale.set_scaling_factor(m.fs.unit.overall_heat_transfer_coefficient,
1e-3)
iscale.set_scaling_factor(m.fs.unit.area, 1)
iscale.calculate_scaling_factors(m)
# ---specifications---
# state variables
m.fs.unit.hot_inlet.flow_mass_phase_comp[0, "Liq", "H2O"].fix(1)
m.fs.unit.hot_inlet.flow_mass_phase_comp[0, "Liq", "TDS"].fix(0.01)
m.fs.unit.hot_inlet.temperature[0].fix(350)
m.fs.unit.hot_inlet.pressure[0].fix(2e5)
m.fs.unit.cold_inlet.flow_mass_phase_comp[0, "Liq", "H2O"].fix(0.5)
m.fs.unit.cold_inlet.flow_mass_phase_comp[0, "Liq", "TDS"].fix(0.01)
m.fs.unit.cold_inlet.temperature[0].fix(298)
m.fs.unit.cold_inlet.pressure[0].fix(2e5)
m.fs.unit.area.fix(5)
m.fs.unit.overall_heat_transfer_coefficient.fix(1000)
# solving
assert_units_consistent(m)
degrees_of_freedom(m)
m.fs.unit.initialize()
solver = get_solver()
results = solver.solve(m, tee=False)
assert_optimal_termination(results)
report_io = StringIO()
m.fs.unit.report(ostream=report_io)
output = """
====================================================================================
Unit : fs.unit Time: 0.0
------------------------------------------------------------------------------------
Unit Performance
Variables:
Key : Value : Fixed : Bounds
HX Area : 5.0000 : True : (0, None)
HX Coefficient : 1000.0 : True : (0, None)
Heat Duty : 89050. : False : (None, None)
Expressions:
Key : Value
Delta T Driving : 17.810
Delta T In : 9.2239
Delta T Out : 30.689
------------------------------------------------------------------------------------
Stream Table
Hot Inlet Hot Outlet Cold Inlet Cold Outlet
flow_mass_phase_comp ('Liq', 'H2O') 1.0000 1.0000 0.50000 0.50000
flow_mass_phase_comp ('Liq', 'TDS') 0.010000 0.010000 0.010000 0.010000
temperature 350.00 328.69 298.00 340.78
pressure 2.0000e+05 2.0000e+05 2.0000e+05 2.0000e+05
====================================================================================
"""
assert output == report_io.getvalue()
def btx(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
# As we lack other example prop packs with units, take the generic
# BT-PR package and change the base units
configuration2 = {
# Specifying components
"components": {
'benzene': {
"type": Component,
"enth_mol_ig_comp": RPP,
"entr_mol_ig_comp": RPP,
"pressure_sat_comp": RPP,
"phase_equilibrium_form": {("Vap", "Liq"): log_fugacity},
"parameter_data": {
"mw": (78.1136E-3, pyunits.kg/pyunits.mol), # [1]
"pressure_crit": (48.9e5, pyunits.Pa), # [1]
"temperature_crit": (562.2, pyunits.K), # [1]
"omega": 0.212, # [1]
"cp_mol_ig_comp_coeff": {
'A': (-3.392E1, pyunits.J/pyunits.mol/pyunits.K), # [1]
'B': (4.739E-1, pyunits.J/pyunits.mol/pyunits.K**2),
'C': (-3.017E-4, pyunits.J/pyunits.mol/pyunits.K**3),
'D': (7.130E-8, pyunits.J/pyunits.mol/pyunits.K**4)},
"enth_mol_form_vap_comp_ref": (
82.9e3, pyunits.J/pyunits.mol), # [3]
"entr_mol_form_vap_comp_ref": (
-269, pyunits.J/pyunits.mol/pyunits.K), # [3]
"pressure_sat_comp_coeff": {'A': (-6.98273, None), # [1]
'B': (1.33213, None),
'C': (-2.62863, None),
'D': (-3.33399, None)}}},
'toluene': {
"type": Component,
"enth_mol_ig_comp": RPP,
"entr_mol_ig_comp": RPP,
"pressure_sat_comp": RPP,
"phase_equilibrium_form": {("Vap", "Liq"): log_fugacity},
"parameter_data": {
"mw": (92.1405E-3, pyunits.kg/pyunits.mol), # [1]
"pressure_crit": (41e5, pyunits.Pa), # [1]
"temperature_crit": (591.8, pyunits.K), # [1]
"omega": 0.263, # [1]
"cp_mol_ig_comp_coeff": {
'A': (-2.435E1, pyunits.J/pyunits.mol/pyunits.K), # [1]
'B': (5.125E-1, pyunits.J/pyunits.mol/pyunits.K**2),
'C': (-2.765E-4, pyunits.J/pyunits.mol/pyunits.K**3),
'D': (4.911E-8, pyunits.J/pyunits.mol/pyunits.K**4)},
"enth_mol_form_vap_comp_ref": (
50.1e3, pyunits.J/pyunits.mol), # [3]
"entr_mol_form_vap_comp_ref": (
-321, pyunits.J/pyunits.mol/pyunits.K), # [3]
"pressure_sat_comp_coeff": {'A': (-7.28607, None), # [1]
'B': (1.38091, None),
'C': (-2.83433, None),
'D': (-2.79168, None)}}}},
# Specifying phases
"phases": {'Liq': {"type": LiquidPhase,
"equation_of_state": Cubic,
"equation_of_state_options": {
"type": CubicType.PR}},
'Vap': {"type": VaporPhase,
"equation_of_state": Cubic,
"equation_of_state_options": {
"type": CubicType.PR}}},
# Set base units of measurement
"base_units": {"time": pyunits.s,
"length": pyunits.m,
"mass": pyunits.t,
"amount": pyunits.mol,
"temperature": pyunits.degR},
# Specifying state definition
"state_definition": FTPx,
"state_bounds": {"flow_mol": (0, 100, 1000, pyunits.mol/pyunits.s),
"temperature": (273.15, 300, 500, pyunits.K),
"pressure": (5e4, 1e5, 1e6, pyunits.Pa)},
"pressure_ref": (101325, pyunits.Pa),
"temperature_ref": (298.15, pyunits.K),
# Defining phase equilibria
"phases_in_equilibrium": [("Vap", "Liq")],
"phase_equilibrium_state": {("Vap", "Liq"): SmoothVLE},
"bubble_dew_method": LogBubbleDew,
"parameter_data": {"PR_kappa": {("benzene", "benzene"): 0.000,
("benzene", "toluene"): 0.000,
("toluene", "benzene"): 0.000,
("toluene", "toluene"): 0.000}}}
m.fs.properties = GenericParameterBlock(default=configuration)
m.fs.properties2 = GenericParameterBlock(default=configuration2)
m.fs.unit = HeatExchanger(default={
"shell": {"property_package": m.fs.properties},
"tube": {"property_package": m.fs.properties2},
"flow_pattern": HeatExchangerFlowPattern.cocurrent})
m.fs.unit.inlet_1.flow_mol[0].fix(5) # mol/s
m.fs.unit.inlet_1.temperature[0].fix(365) # K
m.fs.unit.inlet_1.pressure[0].fix(101325) # Pa
m.fs.unit.inlet_1.mole_frac_comp[0, "benzene"].fix(0.5)
m.fs.unit.inlet_1.mole_frac_comp[0, "toluene"].fix(0.5)
m.fs.unit.inlet_2.flow_mol[0].fix(1) # mol/s
m.fs.unit.inlet_2.temperature[0].fix(540) # degR
m.fs.unit.inlet_2.pressure[0].fix(101.325) # kPa
m.fs.unit.inlet_2.mole_frac_comp[0, "benzene"].fix(0.5)
m.fs.unit.inlet_2.mole_frac_comp[0, "toluene"].fix(0.5)
m.fs.unit.area.fix(1)
m.fs.unit.overall_heat_transfer_coefficient.fix(100)
m.fs.unit.side_2.scaling_factor_pressure = 1
return m
def test_heat_exchanger():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = props.SeawaterParameterBlock()
m.fs.unit = HeatExchanger(
default={
"hot_side_name": "hot",
"cold_side_name": "cold",
"hot": {
"property_package": m.fs.properties
},
"cold": {
"property_package": m.fs.properties
},
"delta_temperature_callback": delta_temperature_chen_callback,
"flow_pattern": HeatExchangerFlowPattern.countercurrent,
})
# 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", "TDS"))
iscale.set_scaling_factor(m.fs.unit.hot.heat, 1e-3)
iscale.set_scaling_factor(m.fs.unit.cold.heat, 1e-3)
iscale.set_scaling_factor(m.fs.unit.overall_heat_transfer_coefficient,
1e-3)
iscale.set_scaling_factor(m.fs.unit.area, 1)
iscale.calculate_scaling_factors(m)
# ---specifications---
# state variables
m.fs.unit.hot_inlet.flow_mass_phase_comp[0, "Liq", "H2O"].fix(1)
m.fs.unit.hot_inlet.flow_mass_phase_comp[0, "Liq", "TDS"].fix(0.01)
m.fs.unit.hot_inlet.temperature[0].fix(350)
m.fs.unit.hot_inlet.pressure[0].fix(2e5)
m.fs.unit.cold_inlet.flow_mass_phase_comp[0, "Liq", "H2O"].fix(0.5)
m.fs.unit.cold_inlet.flow_mass_phase_comp[0, "Liq", "TDS"].fix(0.01)
m.fs.unit.cold_inlet.temperature[0].fix(298)
m.fs.unit.cold_inlet.pressure[0].fix(2e5)
m.fs.unit.area.fix(5)
m.fs.unit.overall_heat_transfer_coefficient.fix(1000)
# solving
assert_units_consistent(m)
degrees_of_freedom(m)
m.fs.unit.initialize()
solver = get_solver()
results = solver.solve(m, tee=False)
assert_optimal_termination(results)
assert pytest.approx(89050.0, rel=1e-4) == value(m.fs.unit.heat_duty[0])
assert pytest.approx(1.0, rel=1e-4) == value(
m.fs.unit.hot_outlet.flow_mass_phase_comp[0, "Liq", "H2O"])
assert pytest.approx(0.01, rel=1e-4) == value(
m.fs.unit.hot_outlet.flow_mass_phase_comp[0, "Liq", "TDS"])
assert pytest.approx(328.69, rel=1e-4) == value(
m.fs.unit.hot_outlet.temperature[0])
assert pytest.approx(2.0e5,
rel=1e-4) == value(m.fs.unit.hot_outlet.pressure[0])
assert pytest.approx(0.5, rel=1e-4) == value(
m.fs.unit.cold_outlet.flow_mass_phase_comp[0, "Liq", "H2O"])
assert pytest.approx(0.01, rel=1e-4) == value(
m.fs.unit.cold_outlet.flow_mass_phase_comp[0, "Liq", "TDS"])
assert pytest.approx(340.78, rel=1e-4) == value(
m.fs.unit.cold_outlet.temperature[0])
assert pytest.approx(2.0e5,
rel=1e-4) == value(m.fs.unit.cold_outlet.pressure[0])
m.fs.unit.report()
