def main():
# set up solver
solver_dict = {
'solver_str': 'ipopt',
'solver_opt': {
'nlp_scaling_method': 'user-scaling'
}
}
solver_dict['solver'] = SolverFactory(solver_dict['solver_str'])
solver_dict['solver'].options = solver_dict['solver_opt']
# build, set, and initialize
m = build()
set_operating_conditions(m, solver=solver_dict['solver'])
initialize_system(m, solver_dict=solver_dict)
# simulate and display
solve(m, solver=solver_dict['solver'])
print('\n***---Simulation results---***')
display_system(m)
display_design(m)
display_state(m)
# optimize and display
optimize(m, solver=solver_dict['solver'])
print('\n***---Optimization results---***')
display_system(m)
display_design(m)
display_state(m)
def unit_frame(self):
m = ConcreteModel()
m.fs = FlowsheetBlock(default={'dynamic': False})
m.fs.properties = props.SeawaterParameterBlock()
m.fs.unit = PressureExchanger(
default={'property_package': m.fs.properties})
# Specify inlet conditions
temperature = 25 + 273.15
flow_vol = 1e-3
lowP_mass_frac_TDS = 0.035
lowP_pressure = 101325
highP_mass_frac_TDS = 0.07
highP_pressure = 50e5
m.fs.unit.low_pressure_side.properties_in[0].flow_vol_phase['Liq'].fix(
flow_vol)
m.fs.unit.low_pressure_side.properties_in[0].mass_frac_phase_comp[
'Liq', 'TDS'].fix(lowP_mass_frac_TDS)
m.fs.unit.low_pressure_side.properties_in[0].pressure.fix(
lowP_pressure)
m.fs.unit.low_pressure_side.properties_in[0].temperature.fix(
temperature)
m.fs.unit.high_pressure_side.properties_in[0].flow_vol_phase[
'Liq'].fix(flow_vol)
m.fs.unit.high_pressure_side.properties_in[0].mass_frac_phase_comp[
'Liq', 'TDS'].fix(highP_mass_frac_TDS)
m.fs.unit.high_pressure_side.properties_in[0].pressure.fix(
highP_pressure)
m.fs.unit.high_pressure_side.properties_in[0].temperature.fix(
temperature)
# solve inlet conditions and only fix state variables (i.e. unfix flow_vol and mass_frac_phase)
solver = SolverFactory('ipopt')
solver.options = {'nlp_scaling_method': 'user-scaling'}
results = solver.solve(m.fs.unit.low_pressure_side.properties_in[0])
assert results.solver.termination_condition == TerminationCondition.optimal
m.fs.unit.low_pressure_side.properties_in[0].flow_mass_phase_comp[
'Liq', 'TDS'].fix()
m.fs.unit.low_pressure_side.properties_in[0].flow_vol_phase[
'Liq'].unfix()
m.fs.unit.low_pressure_side.properties_in[0].mass_frac_phase_comp[
'Liq', 'TDS'].unfix()
results = solver.solve(m.fs.unit.high_pressure_side.properties_in[0])
assert results.solver.termination_condition == TerminationCondition.optimal
m.fs.unit.high_pressure_side.properties_in[0].flow_mass_phase_comp[
'Liq', 'H2O'].fix()
m.fs.unit.high_pressure_side.properties_in[0].flow_mass_phase_comp[
'Liq', 'TDS'].fix()
m.fs.unit.high_pressure_side.properties_in[0].flow_vol_phase[
'Liq'].unfix()
m.fs.unit.high_pressure_side.properties_in[0].mass_frac_phase_comp[
'Liq', 'TDS'].unfix()
# Specify unit
efficiency = 0.95
m.fs.unit.efficiency_pressure_exchanger.fix(efficiency)
return m
def initialize(blk,
state_args=None,
outlvl=idaeslog.NOTSET,
solver='ipopt',
optarg={'tol': 1e-6}):
'''
This is a general purpose initialization routine for simple unit
models. This method assumes a single ControlVolume block called
controlVolume, and first initializes this and then attempts to solve
the entire unit.
More complex models should overload this method with their own
initialization routines,
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) to provide an initial state for
initialization (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating which solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
# Set solver options
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize control volume block
flags = blk.control_volume.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args,
)
init_log.info_high('Initialization Step 1 Complete.')
# ---------------------------------------------------------------------
# Solve unit
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
results = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 2 {}.".format(
idaeslog.condition(results)))
# ---------------------------------------------------------------------
# Release Inlet state
blk.control_volume.release_state(flags, outlvl + 1)
init_log.info('Initialization Complete: {}'.format(
idaeslog.condition(results)))
def initialize(blk,
state_args=None,
outlvl=0,
solver='ipopt',
optarg={'tol': 1e-6}):
'''
Downcomer initialization routine.
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) for the control_volume of the model to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
outlvl : sets output level of initialisation routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
flags = blk.control_volume.initialize(
outlvl=outlvl + 1,
optarg=optarg,
solver=solver,
state_args=state_args,
)
init_log.info_high("Initialization Step 1 Complete.")
# Fix outlet enthalpy and pressure
for t in blk.flowsheet().config.time:
blk.control_volume.properties_out[t].pressure.fix(
value(blk.control_volume.properties_in[t].pressure))
blk.pressure_change_total_eqn.deactivate()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 2 {}.".format(
idaeslog.condition(res)))
# Unfix outlet enthalpy and pressure
for t in blk.flowsheet().config.time:
blk.control_volume.properties_out[t].pressure.unfix()
blk.pressure_change_total_eqn.activate()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 3 {}.".format(
idaeslog.condition(res)))
blk.control_volume.release_state(flags, outlvl + 1)
init_log.info("Initialization Complete.")
def initialize(blk,
state_args_water_steam={},
outlvl=0,
solver='ipopt',
optarg={'tol': 1e-6}):
'''
Drum initialization routine.
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) for the control_volume of the model to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
outlvl : sets output level of initialisation routine
* 0 = no output (default)
* 1 = return solver state for each step in routine
* 2 = return solver state for each step in subroutines
* 3 = include solver output infomation (tee=True)
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
init_log.info_low("Starting initialization...")
# fix FeedWater Inlet
flags_fw = fix_state_vars(blk.mixed_state, state_args_water_steam)
blk.mixed_state.initialize()
# initialize outlet states
for t in blk.flowsheet().config.time:
blk.vap_state[t].flow_mol = value(blk.mixed_state[t].flow_mol *
blk.mixed_state[t].vapor_frac)
blk.vap_state[t].enth_mol = value(
blk.mixed_state[t].enth_mol_phase["Vap"])
blk.vap_state[t].pressure = value(blk.mixed_state[t].pressure)
blk.vap_state[t].vapor_frac = 1
blk.liq_state[t].flow_mol = value(
blk.mixed_state[t].flow_mol *
(1 - blk.mixed_state[t].vapor_frac))
blk.liq_state[t].enth_mol = value(
blk.mixed_state[t].enth_mol_phase["Liq"])
blk.liq_state[t].pressure = value(blk.mixed_state[t].pressure)
blk.liq_state[t].vapor_frac = 0
# unfix variables
revert_state_vars(blk.mixed_state, flags_fw)
init_log.info_low("Initialization Complete.")
def initialize(self, outlvl=idaeslog.NOTSET, optarg={}, solver="ipopt"):
"""
Initialization routine for mixer (default solver ipopt)
Keyword Arguments:
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
"""
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
# Set solver options
opt = SolverFactory(solver)
opt.options = optarg
# This shouldn't require too much initializtion, just fixing inlets
# and solving should always work.
# sp is what to save to make sure state after init is same as the start
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
for b in self.inlet_blocks.values():
for bdat in b.values():
bdat.pressure.fix()
bdat.enth_mol.fix()
bdat.flow_mol.fix()
for t, v in self.outlet.pressure.items():
if not v.fixed:
v.value = min([
value(self.inlet_blocks[i][t].pressure)
for i in self.inlet_blocks
])
self.outlet.unfix()
if (hasattr(self, "pressure_equality_constraints")
and self.pressure_equality_constraints.active):
# If using the equal pressure constraint fix the outlet and free
# the inlet pressures, this is typical for pressure driven flow
for i, b in self.inlet_blocks.items():
for bdat in b.values():
bdat.pressure.unfix()
self.outlet.pressure.fix()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info("Initialization Complete: {}".format(
idaeslog.condition(res)))
from_json(self, sd=istate, wts=sp)
def get_default_solver():
"""
Tries to set-up the default solver for testing, and returns None if not
available
"""
if SolverFactory('ipopt').available(exception_flag=False):
solver = SolverFactory('ipopt')
solver.options = {'tol': 1e-6}
else:
solver = None
return solver
def initialize(self, *args, **kwargs):
"""
Use the regular heat exchanger initialization, with the extraction rate
constraint deactivated; then it activates the constraint and calculates
a steam inlet flow rate.
"""
solver = kwargs.get("solver", "ipopt")
optarg = kwargs.get("oparg", {})
outlvl = kwargs.get("outlvl", idaeslog.NOTSET)
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
self.area.fix()
self.overall_heat_transfer_coefficient.fix()
self.inlet_1.fix()
self.inlet_2.fix()
self.outlet_1.unfix()
self.outlet_2.unfix()
# Do condenser initialization
self.inlet_1.flow_mol.unfix()
# fix volume and pressure drop since
# the condenser initialization dosen't require them
self.side_1.volume.fix(10)
self.side_1.deltaP.fix(0)
self.shell_volume_eqn.deactivate()
self.pressure_change_total_eqn.deactivate()
super().initialize()
self.side_1.volume.unfix()
self.side_1.deltaP.unfix()
self.shell_volume_eqn.activate()
self.pressure_change_total_eqn.activate()
opt = SolverFactory(solver)
opt.options = optarg
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info(
"Initialization Complete (w/ steam flow calc): {}".format(
idaeslog.condition(res)
)
)
from_json(self, sd=istate, wts=sp)
def initialize(blk,
state_args={},
outlvl=0,
solver='ipopt',
optarg={'tol': 1e-6}):
'''
This method initializes the StateJunction block by calling the
initialize method on the property block.
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) to provide an initial state for
initialization (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialisation routine
* 0 = no output (default)
* 1 = return solver state for each step in routine
* 2 = return solver state for each step in subroutines
* 3 = include solver output infomation (tee=True)
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating which solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
# Set solver options
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize control volume block
blk.properties.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
hold_state=False,
**state_args)
if outlvl > 0:
_log.info('{} Initialisation Step Complete.'.format(blk.name))
def initialize(self, *args, **kwargs):
"""
Use the regular heat exchanger initilization, with the extraction rate
constraint deactivated; then it activates the constraint and calculates
a steam inlet flow rate.
"""
self.extraction_rate_constraint.deactivate()
super().initialize(*args, **kwargs)
self.extraction_rate_constraint.activate()
solver = kwargs.get("solver", "ipopt")
optarg = kwargs.get("oparg", {})
outlvl = kwargs.get("outlvl", 0)
opt = SolverFactory(solver)
opt.options = optarg
tee = True if outlvl >= 3 else False
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
self.area.fix()
self.overall_heat_transfer_coefficient.fix()
self.inlet_1.fix()
self.inlet_2.fix()
self.outlet_1.unfix()
self.outlet_2.unfix()
self.inlet_1.flow_mol.unfix()
results = opt.solve(self, tee=tee)
if results.solver.termination_condition == TerminationCondition.optimal:
if outlvl >= 2:
_log.info('{} Initialization Failed.'.format(self.name))
else:
_log.warning('{} Initialization Failed.'.format(self.name))
from_json(self, sd=istate, wts=sp)
def initialize(blk,
state_args_1=None,
state_args_2=None,
state_args_3=None,
outlvl=idaeslog.NOTSET,
solver='ipopt',
optarg={'tol': 1e-6}):
'''
General Heat Exchanger initialisation routine.
Keyword Arguments:
state_args_1 : a dict of arguments to be passed to the property
package(s) for side 1 of the heat exchanger to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
state_args_2 : a dict of arguments to be passed to the property
package(s) for side 2 of the heat exchanger to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
state_args_3 : a dict of arguments to be passed to the property
package(s) for side 3 of the heat exchanger to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
outlvl : sets output level of initialisation routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize inlet property blocks
flags1 = blk.side_1.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_1)
flags2 = blk.side_2.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_2)
flags3 = blk.side_3.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_3)
init_log.info('Initialisation Step 1 Complete.')
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info("Initialization Step 2 Complete: {}".format(
idaeslog.condition(res)))
# ---------------------------------------------------------------------
# Release Inlet state
blk.side_1.release_state(flags1, outlvl)
blk.side_2.release_state(flags2, outlvl)
blk.side_3.release_state(flags3, outlvl)
init_log.info_low("Initialization Complete: {}".format(
idaeslog.condition(res)))
def initialize(self, *args, **kwargs):
outlvl = kwargs.get("outlvl", idaeslog.NOTSET)
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
config = self.config # shorter ref to config for less line splitting
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
# the initialization here isn't straight forward since the heat exchanger
# may have 3 stages and they are countercurrent. For simplicity each
# stage in initialized with the same cooling water inlet conditions then
# the whole feedwater heater is solved together. There are more robust
# approaches which can be implimented if the need arises.
# initialize desuperheat if include
if config.has_desuperheat:
if config.has_drain_cooling:
_set_port(self.desuperheat.inlet_2, self.cooling.inlet_2)
else:
_set_port(self.desuperheat.inlet_2, self.condense.inlet_2)
self.desuperheat.initialize(*args, **kwargs)
self.desuperheat.inlet_1.flow_mol.unfix()
if config.has_drain_mixer:
_set_port(self.drain_mix.steam, self.desuperheat.outlet_1)
else:
_set_port(self.condense.inlet_1, self.desuperheat.outlet_1)
# fix the steam and fwh inlet for init
self.desuperheat.inlet_1.fix()
self.desuperheat.inlet_1.flow_mol.unfix() # unfix for extract calc
# initialize mixer if included
if config.has_drain_mixer:
self.drain_mix.steam.fix()
self.drain_mix.drain.fix()
self.drain_mix.outlet.unfix()
self.drain_mix.initialize(*args, **kwargs)
_set_port(self.condense.inlet_1, self.drain_mix.outlet)
if config.has_desuperheat:
self.drain_mix.steam.unfix()
else:
self.drain_mix.steam.flow_mol.unfix()
# Initialize condense section
if config.has_drain_cooling:
_set_port(self.condense.inlet_2, self.cooling.inlet_2)
self.cooling.inlet_2.fix()
else:
self.condense.inlet_2.fix()
if not config.has_drain_mixer and not config.has_desuperheat:
self.condense.inlet_1.fix()
self.condense.inlet_1.flow_mol.unfix()
tempsat = value(self.condense.shell.properties_in[0].temperature_sat)
temp = value(self.condense.tube.properties_in[0].temperature)
if tempsat - temp < 30:
init_log.warning(
"The steam sat. temperature ({}) is near the feedwater"
" inlet temperature ({})".format(tempsat, temp))
self.condense.initialize(*args, **kwargs)
# Initialize drain cooling if included
if config.has_drain_cooling:
_set_port(self.cooling.inlet_1, self.condense.outlet_1)
self.cooling.initialize(*args, **kwargs)
# Solve all together
opt = SolverFactory(kwargs.get("solver", "ipopt"))
opt.options = kwargs.get("oparg", {})
assert degrees_of_freedom(self) == 0
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info("Condensing shell inlet delta T = {}".format(
value(self.condense.delta_temperature_in[0])))
init_log.info("Condensing Shell outlet delta T = {}".format(
value(self.condense.delta_temperature_out[0])))
init_log.info("Steam Flow = {}".format(
value(self.condense.inlet_1.flow_mol[0])))
init_log.info("Initialization Complete: {}".format(
idaeslog.condition(res)))
from_json(self, sd=istate, wts=sp)
def initialize(self, *args, **kwargs):
config = self.config # sorter ref to config for less line splitting
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
# the initilization here isn't straight forward since the heat exchanger
# may have 3 stages and they are countercurrent. For simplicity each
# stage in initialized with the same cooling water inlet conditions then
# the whole feedwater heater is solved together. There are more robust
# approaches which can be implimented if the need arises.
# initialize desuperheat if include
if config.has_desuperheat:
if config.has_drain_cooling:
_set_port(self.desuperheat.inlet_2, self.cooling.inlet_2)
else:
_set_port(self.desuperheat.inlet_2, self.condense.inlet_2)
self.desuperheat.initialize(*args, **kwargs)
self.desuperheat.inlet_1.flow_mol.unfix()
if config.has_drain_mixer:
_set_port(self.drain_mix.steam, self.desuperheat.outlet_1)
else:
_set_port(self.condense.inlet_1, self.desuperheat.outlet_1)
# fix the steam and fwh inlet for init
self.desuperheat.inlet_1.fix()
self.desuperheat.inlet_1.flow_mol.unfix() #unfix for extract calc
# initialize mixer if included
if config.has_drain_mixer:
self.drain_mix.steam.fix()
self.drain_mix.drain.fix()
self.drain_mix.outlet.unfix()
self.drain_mix.initialize(*args, **kwargs)
_set_port(self.condense.inlet_1, self.drain_mix.outlet)
if config.has_desuperheat:
self.drain_mix.steam.unfix()
else:
self.drain_mix.steam.flow_mol.unfix()
# Initialize condense section
if config.has_drain_cooling:
_set_port(self.condense.inlet_2, self.cooling.inlet_2)
self.cooling.inlet_2.fix()
else:
self.condense.inlet_2.fix()
self.condense.initialize(*args, **kwargs)
# Initialize drain cooling if included
if config.has_drain_cooling:
_set_port(self.cooling.inlet_1, self.condense.outlet_1)
self.cooling.initialize(*args, **kwargs)
# Solve all together
outlvl = kwargs.get("outlvl", 0)
opt = SolverFactory(kwargs.get("solver", "ipopt"))
opt.options = kwargs.get("oparg", {})
tee = True if outlvl >= 3 else False
assert (degrees_of_freedom(self) == 0)
results = opt.solve(self, tee=tee)
if results.solver.termination_condition == TerminationCondition.optimal:
if outlvl >= 2:
_log.info('{} Initialization Complete.'.format(self.name))
else:
_log.warning('{} Initialization Failed.'.format(self.name))
from_json(self, sd=istate, wts=sp)
def initialize(
self,
state_args_1=None,
state_args_2=None,
outlvl=idaeslog.NOTSET,
solver="ipopt",
optarg={"tol": 1e-6},
duty=None,
):
"""
Heat exchanger initialization method.
Args:
state_args_1 : a dict of arguments to be passed to the property
initialization for the hot side (see documentation of the specific
property package) (default = {}).
state_args_2 : a dict of arguments to be passed to the property
initialization for the cold side (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating which solver to use during
initialization (default = 'ipopt')
duty : an initial guess for the amount of heat transfered. This
should be a tuple in the form (value, units), (default
= (1000 J/s))
Returns:
None
"""
# Set solver options
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
hot_side = getattr(self, self.config.hot_side_name)
cold_side = getattr(self, self.config.cold_side_name)
opt = SolverFactory(solver)
opt.options = optarg
flags1 = hot_side.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_1)
init_log.info_high("Initialization Step 1a (hot side) Complete.")
flags2 = cold_side.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_2)
init_log.info_high("Initialization Step 1b (cold side) Complete.")
# ---------------------------------------------------------------------
# Solve unit without heat transfer equation
# if costing block exists, deactivate
if hasattr(self, "costing"):
self.costing.deactivate()
self.heat_transfer_equation.deactivate()
# Get side 1 and side 2 heat units, and convert duty as needed
s1_units = hot_side.heat.get_units()
s2_units = cold_side.heat.get_units()
if duty is None:
# Assume 1000 J/s and check for unitless properties
if s1_units is None and s2_units is None:
# Backwards compatability for unitless properties
s1_duty = -1000
s2_duty = 1000
else:
s1_duty = pyunits.convert_value(-1000,
from_units=pyunits.W,
to_units=s1_units)
s2_duty = pyunits.convert_value(1000,
from_units=pyunits.W,
to_units=s2_units)
else:
# Duty provided with explicit units
s1_duty = -pyunits.convert_value(
duty[0], from_units=duty[1], to_units=s1_units)
s2_duty = pyunits.convert_value(duty[0],
from_units=duty[1],
to_units=s2_units)
cold_side.heat.fix(s2_duty)
for i in hot_side.heat:
hot_side.heat[i].value = s1_duty
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info_high("Initialization Step 2 {}.".format(
idaeslog.condition(res)))
cold_side.heat.unfix()
self.heat_transfer_equation.activate()
# ---------------------------------------------------------------------
# Solve unit
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info_high("Initialization Step 3 {}.".format(
idaeslog.condition(res)))
# ---------------------------------------------------------------------
# Release Inlet state
hot_side.release_state(flags1, outlvl=outlvl)
cold_side.release_state(flags2, outlvl=outlvl)
init_log.info("Initialization Completed, {}".format(
idaeslog.condition(res)))
# if costing block exists, activate and initialize
if hasattr(self, "costing"):
self.costing.activate()
costing.initialize(self.costing)
def initialize(
self,
state_args={},
outlvl=idaeslog.NOTSET,
solver="ipopt",
optarg={
"tol": 1e-6,
"max_iter": 30
},
calculate_cf=True,
):
"""
Initialize the outlet turbine stage model. This deactivates the
specialized constraints, then does the isentropic turbine initialization,
then reactivates the constraints and solves.
Args:
state_args (dict): Initial state for property initialization
outlvl : sets output level of initialization routine
solver (str): Solver to use for initialization
optarg (dict): Solver arguments dictionary
"""
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
# sp is what to save to make sure state after init is same as the start
# saves value, fixed, and active state, doesn't load originally free
# values, this makes sure original problem spec is same but initializes
# the values of free vars
for t in self.flowsheet().config.time:
if self.outlet.pressure[t].fixed:
self.ratioP[t] = value(self.outlet.pressure[t] /
self.inlet.pressure[t])
self.deltaP[t] = value(self.outlet.pressure[t] -
self.inlet.pressure[t])
# Deactivate special constraints
self.stodola_equation.deactivate()
self.efficiency_correlation.deactivate()
self.efficiency_isentropic.fix()
self.deltaP.unfix()
self.ratioP.unfix()
self.inlet.fix()
self.outlet.unfix()
super().initialize(outlvl=outlvl, solver=solver, optarg=optarg)
for t in self.flowsheet().config.time:
mw = self.control_volume.properties_in[t].mw
Tin = self.control_volume.properties_in[t].temperature
Pin = self.control_volume.properties_in[t].pressure
Pr = self.ratioP[t]
if not calculate_cf:
cf = self.flow_coeff
self.inlet.flow_mol[t].fix(
value(cf * Pin * sqrt(1 - Pr**2) / mw / sqrt(Tin)))
super().initialize(outlvl=outlvl, solver=solver, optarg=optarg)
self.control_volume.properties_out[:].pressure.fix()
# Free eff_isen and activate sepcial constarints
self.efficiency_isentropic.unfix()
self.outlet.pressure.fix()
if calculate_cf:
self.flow_coeff.unfix()
self.inlet.flow_mol.unfix()
self.inlet.flow_mol[0].fix()
flow = self.control_volume.properties_in[0].flow_mol
mw = self.control_volume.properties_in[0].mw
Tin = self.control_volume.properties_in[0].temperature
Pin = self.control_volume.properties_in[0].pressure
Pr = self.ratioP[0]
self.flow_coeff.value = value(flow * mw * sqrt(Tin / (1 - Pr**2)) /
Pin)
else:
self.inlet.flow_mol.unfix()
self.stodola_equation.activate()
self.efficiency_correlation.activate()
slvr = SolverFactory(solver)
slvr.options = optarg
self.display()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = slvr.solve(self, tee=slc.tee)
init_log.info("Initialization Complete (Outlet Stage): {}".format(
idaeslog.condition(res)))
# reload original spec
if calculate_cf:
cf = value(self.flow_coeff)
from_json(self, sd=istate, wts=sp)
if calculate_cf:
# cf was probably fixed, so will have to set the value agian here
# if you ask for it to be calculated.
self.flow_coeff = cf
import pytest
from pyomo.environ import ConcreteModel, SolverFactory, TransformationFactory
from idaes.core import FlowsheetBlock
from idaes.unit_models.power_generation import SteamValve
from idaes.property_models import iapws95
from idaes.core.util.model_statistics import (degrees_of_freedom,
activated_equalities_generator)
prop_available = iapws95.iapws95_available()
# See if ipopt is available and set up solver
if SolverFactory('ipopt').available():
solver = SolverFactory('ipopt')
solver.options = {'tol': 1e-6}
else:
solver = None
@pytest.fixture()
def build_valve_vapor():
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
m.fs.properties = iapws95.Iapws95ParameterBlock()
m.fs.valve = SteamValve(default={"property_package": m.fs.properties})
return m
@pytest.fixture()
def build_valve_liquid():
def initialize(self,
state_args_1=None,
state_args_2=None,
outlvl=0,
solver='ipopt',
optarg={'tol': 1e-6},
duty=1000):
"""
Heat exchanger initialization method.
Args:
state_args_1 : a dict of arguments to be passed to the property
initialization for shell (see documentation of the specific
property package) (default = {}).
state_args_2 : a dict of arguments to be passed to the property
initialization for tube (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialisation routine
* 0 = no output (default)
* 1 = return solver state for each step in routine
* 2 = return solver state for each step in subroutines
* 3 = include solver output infomation (tee=True)
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating which solver to use during
initialization (default = 'ipopt')
duty : an initial guess for the amount of heat transfered
(default = 10000)
Returns:
None
"""
# Set solver options
tee = True if outlvl >= 3 else False
opt = SolverFactory(solver)
opt.options = optarg
flags1 = self.shell.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
state_args=state_args_1)
if outlvl > 0:
_log.info('{} Initialization Step 1a (shell) Complete.'.format(
self.name))
flags2 = self.tube.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
state_args=state_args_2)
if outlvl > 0:
_log.info('{} Initialization Step 1b (tube) Complete.'.format(
self.name))
# ---------------------------------------------------------------------
# Solve unit without heat transfer equation
self.heat_transfer_equation.deactivate()
self.tube.heat.fix(duty)
results = opt.solve(self, tee=tee, symbolic_solver_labels=True)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
_log.info('{} Initialization Step 2 Complete.'.format(
self.name))
else:
_log.warning('{} Initialization Step 2 Failed.'.format(
self.name))
self.tube.heat.unfix()
self.heat_transfer_equation.activate()
# ---------------------------------------------------------------------
# Solve unit
results = opt.solve(self, tee=tee, symbolic_solver_labels=True)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
_log.info('{} Initialization Step 3 Complete.'.format(
self.name))
else:
_log.warning('{} Initialization Step 3 Failed.'.format(
self.name))
# ---------------------------------------------------------------------
# Release Inlet state
self.shell.release_state(flags1, outlvl - 1)
self.tube.release_state(flags2, outlvl - 1)
if outlvl > 0:
_log.info('{} Initialization Complete.'.format(self.name))
def initialize(self, state_args={}, outlvl=0, solver='ipopt',
optarg={'tol': 1e-6, 'max_iter':30}):
"""
Initialize the inlet turbine stage model. This deactivates the
specialized constraints, then does the isentropic turbine initialization,
then reactivates the constraints and solves.
Args:
state_args (dict): Initial state for property initialization
outlvl (int): Amount of output (0 to 3) 0 is lowest
solver (str): Solver to use for initialization
optarg (dict): Solver arguments dictionary
"""
stee = True if outlvl >= 3 else False
# sp is what to save to make sure state after init is same as the start
# saves value, fixed, and active state, doesn't load originally free
# values, this makes sure original problem spec is same but initializes
# the values of free vars
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
# Deactivate special constraints
self.inlet_flow_constraint.deactivate()
self.isentropic_enthalpy.deactivate()
self.efficiency_correlation.deactivate()
self.deltaP.unfix()
self.ratioP.unfix()
# Fix turbine parameters + eff_isen
self.eff_nozzle.fix()
self.blade_reaction.fix()
self.flow_coeff.fix()
self.blade_velocity.fix()
# fix inlet and free outlet
for t in self.flowsheet().config.time:
for k, v in self.inlet.vars.items():
v[t].fix()
for k, v in self.outlet.vars.items():
v[t].unfix()
# If there isn't a good guess for efficeny or outlet pressure
# provide something reasonable.
eff = self.efficiency_isentropic[t]
eff.fix(eff.value if value(eff) > 0.3 and value(eff) < 1.0 else 0.8)
# for outlet pressure try outlet pressure, pressure ratio, delta P,
# then if none of those look reasonable use a pressure ratio of 0.8
# to calculate outlet pressure
Pout = self.outlet.pressure[t]
Pin = self.inlet.pressure[t]
prdp = value((self.deltaP[t] - Pin)/Pin)
if value(Pout/Pin) > 0.98 or value(Pout/Pin) < 0.3:
if value(self.ratioP[t]) < 0.98 and value(self.ratioP[t]) > 0.3:
Pout.fix(value(Pin*self.ratioP))
elif prdp < 0.98 and prdp > 0.3:
Pout.fix(value(prdp*Pin))
else:
Pout.fix(value(Pin*0.8))
else:
Pout.fix()
self.deltaP[:] = value(Pout - Pin)
self.ratioP[:] = value(Pout/Pin)
for t in self.flowsheet().config.time:
self.properties_isentropic[t].pressure.value = \
value(self.outlet.pressure[t])
self.properties_isentropic[t].flow_mol.value = \
value(self.inlet.flow_mol[t])
self.properties_isentropic[t].enth_mol.value = \
value(self.inlet.enth_mol[t]*0.95)
self.outlet.flow_mol[t].value = \
value(self.inlet.flow_mol[t])
self.outlet.enth_mol[t].value = \
value(self.inlet.enth_mol[t]*0.95)
# Make sure the initialization problem has no degrees of freedom
# This shouldn't happen here unless there is a bug in this
dof = degrees_of_freedom(self)
try:
assert(dof == 0)
except:
_log.exception("degrees_of_freedom = {}".format(dof))
raise
# one bad thing about reusing this is that the log messages aren't
# really compatible with being nested inside another initialization
super(TurbineInletStageData, self).initialize(state_args=state_args,
outlvl=outlvl, solver=solver, optarg=optarg)
# Free eff_isen and activate sepcial constarints
self.efficiency_isentropic.unfix()
self.outlet.pressure.unfix()
self.inlet_flow_constraint.activate()
self.isentropic_enthalpy.activate()
self.efficiency_correlation.activate()
slvr = SolverFactory(solver)
slvr.options = optarg
res = slvr.solve(self, tee=stee)
if outlvl > 0:
if res.solver.termination_condition == TerminationCondition.optimal:
_log.info("{} Initialization Complete.".format(self.name))
else:
_log.warning(
"""{} Initialization Failed. The most likely cause of initialization failure for
the Turbine inlet stages model is that the flow coefficient is not compatible
with flow rate guess.""".format(self.name))
# reload original spec
from_json(self, sd=istate, wts=sp)
def init_isentropic(blk, state_args, outlvl, solver, optarg):
'''
Initialisation routine for unit (default solver ipopt)
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) to provide an initial state for
initialization (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialisation routine
* 0 = no output (default)
* 1 = return solver state for each step in routine
* 2 = return solver state for each step in subroutines
* 3 = include solver output infomation (tee=True)
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
# Set solver options
if outlvl > 3:
stee = True
else:
stee = False
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize Isentropic block
blk.control_volume.properties_in.initialize(outlvl=outlvl-1,
optarg=optarg,
solver=solver,
state_args=state_args)
if outlvl > 0:
logger.info('{} Initialisation Step 1 Complete.'.format(blk.name))
# ---------------------------------------------------------------------
# Initialize holdup block
flags = blk.control_volume.initialize(outlvl=outlvl-1,
optarg=optarg,
solver=solver,
state_args=state_args)
if outlvl > 0:
logger.info('{} Initialisation Step 2 Complete.'.format(blk.name))
# ---------------------------------------------------------------------
# Solve for isothermal conditions
if isinstance(
blk.control_volume.properties_in[
blk.flowsheet().config.time[1]].temperature,
Var):
for t in blk.flowsheet().config.time:
blk.control_volume.properties_in[t].temperature.fix()
blk.isentropic.deactivate()
results = opt.solve(blk, tee=stee)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
logger.info('{} Initialisation Step 3 Complete.'
.format(blk.name))
else:
logger.warning('{} Initialisation Step 3 Failed.'
.format(blk.name))
for t in blk.flowsheet().config.time:
blk.control_volume.properties_in[t].temperature.unfix()
blk.isentropic.activate()
elif outlvl > 0:
logger.info('{} Initialisation Step 3 Skipped.'.format(blk.name))
# ---------------------------------------------------------------------
# Solve unit
results = opt.solve(blk, tee=stee)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
logger.info('{} Initialisation Step 4 Complete.'
.format(blk.name))
else:
logger.warning('{} Initialisation Step 4 Failed.'
.format(blk.name))
# ---------------------------------------------------------------------
# Release Inlet state
blk.control_volume.release_state(flags, outlvl-1)
if outlvl > 0:
logger.info('{} Initialisation Complete.'.format(blk.name))
def initialize(
self,
state_args={},
outlvl=idaeslog.NOTSET,
solver="ipopt",
optarg={"tol": 1e-6, "max_iter": 30},
calculate_cf=False,
):
"""
Initialize the inlet turbine stage model. This deactivates the
specialized constraints, then does the isentropic turbine initialization,
then reactivates the constraints and solves. This initializtion uses a
flow value guess, so some reasonable flow guess should be sepecified prior
to initializtion.
Args:
state_args (dict): Initial state for property initialization
outlvl (int): Amount of output (0 to 3) 0 is lowest
solver (str): Solver to use for initialization
optarg (dict): Solver arguments dictionary
calculate_cf (bool): If True, use the flow and pressure ratio to
calculate the flow coefficient.
"""
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
# sp is what to save to make sure state after init is same as the start
sp = StoreSpec.value_isfixed_isactive(only_fixed=True)
istate = to_json(self, return_dict=True, wts=sp)
# Setup for initializtion step 1
self.inlet_flow_constraint.deactivate()
self.efficiency_correlation.deactivate()
self.eff_nozzle.fix()
self.blade_reaction.fix()
self.flow_coeff.fix()
self.blade_velocity.fix()
self.inlet.fix()
self.outlet.unfix()
for t in self.flowsheet().config.time:
self.efficiency_isentropic[t] = 0.9
super().initialize(outlvl=outlvl, solver=solver, optarg=optarg)
# Free eff_isen and activate sepcial constarints
self.inlet_flow_constraint.activate()
self.efficiency_correlation.activate()
if calculate_cf:
self.ratioP.fix()
self.flow_coeff.unfix()
for t in self.flowsheet().config.time:
g = self.control_volume.properties_in[t].heat_capacity_ratio
mw = self.control_volume.properties_in[t].mw
flow = self.control_volume.properties_in[t].flow_mol
Tin = self.control_volume.properties_in[t].temperature
Pin = self.control_volume.properties_in[t].pressure
Pratio = self.ratioP[t]
self.flow_coeff[t].value = value(
flow * mw * sqrt(
Tin/(g/(g - 1) *(Pratio**(2.0/g) - Pratio**((g + 1)/g)))
)/Pin
)
slvr = SolverFactory(solver)
slvr.options = optarg
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = slvr.solve(self, tee=slc.tee)
init_log.info("Initialization Complete: {}".format(idaeslog.condition(res)))
# reload original spec
if calculate_cf:
cf = {}
for t in self.flowsheet().config.time:
cf[t] = value(self.flow_coeff[t])
from_json(self, sd=istate, wts=sp)
if calculate_cf:
# cf was probably fixed, so will have to set the value agian here
# if you ask for it to be calculated.
for t in self.flowsheet().config.time:
self.flow_coeff[t] = cf[t]
def initialize(
self,
state_args_1=None,
state_args_2=None,
outlvl=idaeslog.NOTSET,
solver="ipopt",
optarg={"tol": 1e-6},
duty=1000,
):
"""
Heat exchanger initialization method.
Args:
state_args_1 : a dict of arguments to be passed to the property
initialization for side_1 (see documentation of the specific
property package) (default = {}).
state_args_2 : a dict of arguments to be passed to the property
initialization for side_2 (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating which solver to use during
initialization (default = 'ipopt')
duty : an initial guess for the amount of heat transfered
(default = 10000)
Returns:
None
"""
# Set solver options
init_log = idaeslog.getInitLogger(self.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(self.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
flags1 = self.side_1.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_1)
init_log.info_high("Initialization Step 1a (side_1) Complete.")
flags2 = self.side_2.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_2)
init_log.info_high("Initialization Step 1b (side_2) Complete.")
# ---------------------------------------------------------------------
# Solve unit without heat transfer equation
self.heat_transfer_equation.deactivate()
self.side_2.heat.fix(duty)
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info_high("Initialization Step 2 {}.".format(
idaeslog.condition(res)))
self.side_2.heat.unfix()
self.heat_transfer_equation.activate()
# ---------------------------------------------------------------------
# Solve unit
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(self, tee=slc.tee)
init_log.info_high("Initialization Step 3 {}.".format(
idaeslog.condition(res)))
# ---------------------------------------------------------------------
# Release Inlet state
self.side_1.release_state(flags1, outlvl=outlvl)
self.side_2.release_state(flags2, outlvl=outlvl)
init_log.info("Initialization Completed, {}".format(
idaeslog.condition(res)))
def initialize(blk, outlvl=0, optarg={}, solver='ipopt', hold_state=False):
'''
Initialisation routine for mixer (default solver ipopt)
Keyword Arguments:
outlvl : sets output level of initialisation routine. **Valid
values:** **0** - no output (default), **1** - return
solver state for each step in routine, **2** - include
solver output infomation (tee=True)
optarg : solver options dictionary object (default={})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
hold_state : flag indicating whether the initialization routine
should unfix any state variables fixed during
initialization, **default** - False. **Valid values:**
**True** - states variables are not unfixed, and a dict of
returned containing flags for which states were fixed
during initialization, **False** - state variables are
unfixed after initialization by calling the release_state
method.
Returns:
If hold_states is True, returns a dict containing flags for which
states were fixed during initialization.
'''
# Set solver options
if outlvl > 1:
stee = True
else:
stee = False
opt = SolverFactory(solver)
opt.options = optarg
# Initialize inlet state blocks
flags = {}
inlet_list = blk.create_inlet_list()
i_block_list = []
for i in inlet_list:
i_block = getattr(blk, i + "_state")
i_block_list.append(i_block)
flags[i] = {}
flags[i] = i_block.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
hold_state=True)
# Initialize mixed state block
if blk.config.mixed_state_block is None:
mblock = blk.mixed_state
else:
mblock = blk.config.mixed_state_block
# Calculate initial guesses for mixed stream state
for t in blk.flowsheet().config.time:
# Iterate over state vars as defined by property package
s_vars = mblock[t].define_state_vars()
for s in s_vars:
i_vars = []
for i in range(len(i_block_list)):
i_vars.append(
getattr(i_block_list[i][t], s_vars[s].local_name))
if s == "pressure":
# If pressure, use minimum as initial guess
mblock[t].pressure.value = min(
i_block_list[i][t].pressure.value
for i in range(len(i_block_list)))
elif "flow" in s:
# If a "flow" variable (i.e. extensive), sum inlets
for k in s_vars[s]:
s_vars[s][k].value = sum(
i_vars[i][k].value
for i in range(len(i_block_list)))
else:
# Otherwise use average of inlets
for k in s_vars[s]:
s_vars[s][k].value = (
sum(i_vars[i][k].value
for i in range(len(i_block_list))) /
len(i_block_list))
mblock.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
hold_state=False)
if blk.config.mixed_state_block is None:
if (hasattr(blk, "pressure_equality_constraints")
and blk.pressure_equality_constraints.active is True):
blk.pressure_equality_constraints.deactivate()
for t in blk.flowsheet().config.time:
sys_press = getattr(blk,
blk.create_inlet_list()[0] +
"_state")[t].pressure
blk.mixed_state[t].pressure.fix(sys_press.value)
results = opt.solve(blk, tee=stee)
blk.pressure_equality_constraints.activate()
for t in blk.flowsheet().config.time:
blk.mixed_state[t].pressure.unfix()
else:
results = opt.solve(blk, tee=stee)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
_log.info('{} Initialisation Complete.'.format(blk.name))
else:
_log.warning('{} Initialisation Failed.'.format(blk.name))
else:
_log.info('{} Initialisation Complete.'.format(blk.name))
if hold_state is True:
return flags
else:
blk.release_state(flags, outlvl=outlvl - 1)
Author: Jaffer Ghouse
"""
import pytest
from pyomo.environ import ConcreteModel, SolverFactory, TerminationCondition, \
SolverStatus, value
from pyomo.util.check_units import assert_units_consistent
from idaes.core import FlowsheetBlock
from idaes.generic_models.properties.activity_coeff_models.BTX_activity_coeff_VLE \
import BTXParameterBlock
from idaes.core.util.model_statistics import degrees_of_freedom
# See if ipopt is available and set up solver
if SolverFactory('ipopt').available():
solver = SolverFactory('ipopt')
solver.options = {'tol': 1e-6, 'mu_init': 1e-8, 'bound_push': 1e-8}
else:
solver = None
# -----------------------------------------------------------------------------
# Create a flowsheet for test
m = ConcreteModel()
m.fs = FlowsheetBlock(default={"dynamic": False})
# vapor-liquid (ideal) - FTPz
m.fs.properties_ideal_vl_FTPz = BTXParameterBlock(
default={
"valid_phase": ('Liq', 'Vap'),
"activity_coeff_model": "Ideal",
"state_vars": "FTPz"
})
m.fs.state_block_ideal_vl_FTPz = m.fs.properties_ideal_vl_FTPz.build_state_block(
def initialize(blk, state_args_PA=None, state_args_SA=None,
outlvl=idaeslog.NOTSET, solver='ipopt',
optarg={'tol': 1e-6}):
'''
Initialization routine.
1.- initialize state blocks, using an initial guess for inlet
primary air and secondary air.
2.- Use PA and SA values to guess flue gas component molar flowrates,
Temperature, and Pressure. Initialize flue gas state block.
3.- Then, solve complete model.
Keyword Arguments:
state_args_PA : a dict of arguments to be passed to the property
package(s) for the primary air state block to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
state_args_SA : a dict of arguments to be passed to the property
package(s) for secondary air state block to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
outlvl : sets output level of initialisation routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize inlet property blocks
blk.primary_air.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_PA
)
blk.primary_air_moist.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_PA
)
blk.secondary_air.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=state_args_SA
)
init_log.info_high("Initialization Step 1 Complete.")
state_args = {"flow_mol_comp": {"H2O": (blk.primary_air_inlet.
flow_mol_comp[0, "H2O"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "H2O"].value),
"CO2": (blk.primary_air_inlet.
flow_mol_comp[0, "CO2"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "CO2"].value),
"N2": (blk.primary_air_inlet.
flow_mol_comp[0, "N2"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "N2"].value),
"O2": (blk.primary_air_inlet.
flow_mol_comp[0, "O2"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "O2"].value),
"SO2": (blk.primary_air_inlet.
flow_mol_comp[0, "SO2"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "SO2"].value),
"NO": (blk.primary_air_inlet.
flow_mol_comp[0, "NO"].value
+ blk.secondary_air_inlet.
flow_mol_comp[0, "NO"].value)},
"temperature": 1350.00,
"pressure": blk.primary_air_inlet.pressure[0].value}
# initialize flue gas outlet
blk.flue_gas.initialize(state_args=state_args,
outlvl=outlvl,
solver=solver)
init_log.info_high("Initialization Step 2 Complete.")
if blk.config.calculate_PA_SA_flows is False:
# Option 1: given PA and SA component flow rates - fixed inlets
# fix inlet component molar flow rates
# unfix ratio_PA2coal, SR, and fluegas_o2_pct_dry
blk.primary_air_inlet.flow_mol_comp[...].fix()
blk.secondary_air_inlet.flow_mol_comp[...].fix()
blk.ratio_PA2coal.unfix()
blk.SR.unfix()
blk.fluegas_o2_pct_dry.unfix()
dof = degrees_of_freedom(blk)
else:
# Option 2: SR, ratioPA2_coal to estimate TCA, PA, SA
# unfix component molar flow rates, but keep T and P fixed.
blk.primary_air_inlet.flow_mol_comp[:, :].unfix()
blk.secondary_air_inlet.flow_mol_comp[:, :].unfix()
dof = degrees_of_freedom(blk)
if not dof == 0:
raise ConfigurationError('User needs to check '
'degrees of freedom')
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high(
"Initialization Step 3 {}.".format(idaeslog.condition(res))
)
init_log.info("Initialization Complete.")
def initialize(blk, outlvl=6, optarg={}, solver="ipopt", hold_state=False):
"""
Initialization routine for mixer (default solver ipopt)
Keyword Arguments:
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
hold_state : flag indicating whether the initialization routine
should unfix any state variables fixed during
initialization, **default** - False. **Valid values:**
**True** - states variables are not unfixed, and a dict of
returned containing flags for which states were fixed
during initialization, **False** - state variables are
unfixed after initialization by calling the release_state
method.
Returns:
If hold_states is True, returns a dict containing flags for which
states were fixed during initialization.
"""
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
# Set solver options
opt = SolverFactory(solver)
opt.options = optarg
# Initialize inlet state blocks
flags = {}
inlet_list = blk.create_inlet_list()
i_block_list = []
for i in inlet_list:
i_block = getattr(blk, i + "_state")
i_block_list.append(i_block)
flags[i] = {}
flags[i] = i_block.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
hold_state=True,
)
# Initialize mixed state block
if blk.config.mixed_state_block is None:
mblock = blk.mixed_state
else:
mblock = blk.config.mixed_state_block
o_flags = {}
# Calculate initial guesses for mixed stream state
for t in blk.flowsheet().config.time:
# Iterate over state vars as defined by property package
s_vars = mblock[t].define_state_vars()
for s in s_vars:
i_vars = []
for k in s_vars[s]:
# Record whether variable was fixed or not
o_flags[t, s, k] = s_vars[s][k].fixed
# If fixed, use current value
# otherwise calculate guess from mixed state
if not s_vars[s][k].fixed:
for i in range(len(i_block_list)):
i_vars.append(
getattr(i_block_list[i][t],
s_vars[s].local_name)
)
if s == "pressure":
# If pressure, use minimum as initial guess
mblock[t].pressure.value = min(
i_block_list[i][t].pressure.value
for i in range(len(i_block_list))
)
elif "flow" in s:
# If a "flow" variable (i.e. extensive), sum inlets
for k in s_vars[s]:
s_vars[s][k].value = sum(
i_vars[i][k].value for i in range(
len(i_block_list))
)
else:
# Otherwise use average of inlets
for k in s_vars[s]:
s_vars[s][k].value = sum(
i_vars[i][k].value for i in range(
len(i_block_list))
) / len(i_block_list)
mblock.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
hold_state=False,
)
# Revert fixed status of variables to what they were before
for t in blk.flowsheet().config.time:
s_vars = mblock[t].define_state_vars()
for s in s_vars:
for k in s_vars[s]:
s_vars[s][k].fixed = o_flags[t, s, k]
if blk.config.mixed_state_block is None:
if (
hasattr(blk, "pressure_equality_constraints")
and blk.pressure_equality_constraints.active is True
):
blk.pressure_equality_constraints.deactivate()
for t in blk.flowsheet().config.time:
sys_press = getattr(
blk,
blk.create_inlet_list()[0] + "_state")[t].pressure
blk.mixed_state[t].pressure.fix(sys_press.value)
with idaeslog.solver_log(solve_log, idaeslog.DEBUG)as slc:
res = opt.solve(blk, tee=slc.tee)
blk.pressure_equality_constraints.activate()
for t in blk.flowsheet().config.time:
blk.mixed_state[t].pressure.unfix()
else:
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info(
"Initialization Complete: {}".format(idaeslog.condition(res))
)
else:
init_log.info("Initialization Complete.")
if hold_state is True:
return flags
else:
blk.release_state(flags, outlvl=outlvl)
def initialize(
blk,
shell_state_args=None,
tube_state_args=None,
outlvl=idaeslog.NOTSET,
solver="ipopt",
optarg={"tol": 1e-6},
):
"""
Initialization routine for the unit (default solver ipopt).
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) to provide an initial state for
initialization (see documentation of the specific
property package) (default = {}).
outlvl : sets output level of initialization routine
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
"""
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
# ---------------------------------------------------------------------
# Initialize shell block
flags_shell = blk.shell.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=shell_state_args,
)
flags_tube = blk.tube.initialize(
outlvl=outlvl,
optarg=optarg,
solver=solver,
state_args=tube_state_args,
)
init_log.info_high("Initialization Step 1 Complete.")
# ---------------------------------------------------------------------
# Solve unit
# Wall 0D
if blk.config.has_wall_conduction == WallConductionType.zero_dimensional:
shell_units = \
blk.config.shell_side.property_package.get_metadata().get_derived_units
for t in blk.flowsheet().config.time:
for z in blk.shell.length_domain:
blk.temperature_wall[t, z].fix(
value(0.5 *
(blk.shell.properties[t, 0].temperature +
pyunits.convert(
blk.tube.properties[t, 0].temperature,
to_units=shell_units('temperature')))))
blk.tube.deactivate()
blk.tube_heat_transfer_eq.deactivate()
blk.wall_0D_model.deactivate()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 2 {}.".format(
idaeslog.condition(res)))
blk.tube.activate()
blk.tube_heat_transfer_eq.activate()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 3 {}.".format(
idaeslog.condition(res)))
blk.wall_0D_model.activate()
blk.temperature_wall.unfix()
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high("Initialization Step 4 {}.".format(
idaeslog.condition(res)))
blk.shell.release_state(flags_shell)
blk.tube.release_state(flags_tube)
init_log.info("Initialization Complete.")
"energy_mixing_type": MixingType.extensive,
"momentum_mixing_type": MomentumMixingType.none
})
m.fs.Mixer.feed_1.flow_mass[0].fix(0.5)
m.fs.Mixer.feed_1.mass_frac[0].fix(0.1)
m.fs.Mixer.feed_1.temperature[0].fix(273.15 + 50)
m.fs.Mixer.feed_2.flow_mass[0].fix(0.5)
m.fs.Mixer.feed_2.mass_frac[0].fix(0.035)
m.fs.Mixer.feed_2.temperature[0].fix(273.15 + 25)
# m.fs.Mixer.outlet.temperature[0].fix(273.15 + 40)
# m.fs.Mixer.mixed_state[0].dens_mass
# m.fs.Mixer.mixed_state[0].viscosity
# m.fs.Mixer.mixed_state[0].dens_mass_comp
m.fs.Mixer.mixed_state[0].pressure_osm
# m.fs.Mixer.mixed_state[0].osm_coeff
# m.fs.Mixer.mixed_state[0].enth_mass_liq
m.fs.Mixer.initialize(outlvl=0)
print("Degrees of Freedom =", degrees_of_freedom(m))
assert degrees_of_freedom(m) == 0
solver = SolverFactory('ipopt')
solver.options = {'tol': 1e-6, 'max_iter': 5000}
results = solver.solve(m, tee=False)
assert results.solver.termination_condition == TerminationCondition.optimal
# m.display()
#
m.fs.Mixer.display()
for p in m.fs.Mixer.component_objects(Port, descend_into=True):
p.display()
# m.fs.Mixer.pprint()
from collections import OrderedDict
import random
import time as timemodule
import enum
import pdb
__author__ = "Robert Parker and David Thierry"
# TODO: clean up this file - add license, remove solver_available
# See if ipopt is available and set up solver
solver_available = SolverFactory('ipopt').available()
if solver_available:
solver = SolverFactory('ipopt')
solver.options = {'tol': 1e-6,
'mu_init': 1e-8,
'bound_push': 1e-8,
'halt_on_ampl_error': 'yes'}
else:
solver = None
class CachedVarsContext(object):
def __init__(self, varlist, nvars, tlist):
if type(tlist) is not list:
tlist = [tlist]
self.n_t = len(tlist)
self.vars = varlist
self.nvars = nvars
self.tlist = tlist
self.cache = [[None for j in range(self.n_t)]
for i in range(self.nvars)]
def initialize(blk, outlvl=0, optarg={}, solver='ipopt', hold_state=False):
'''
Initialisation routine for separator (default solver ipopt)
Keyword Arguments:
outlvl : sets output level of initialisation routine. **Valid
values:** **0** - no output (default), **1** - return
solver state for each step in routine, **2** - include
solver output infomation (tee=True)
optarg : solver options dictionary object (default=None)
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
hold_state : flag indicating whether the initialization routine
should unfix any state variables fixed during
initialization, **default** - False. **Valid values:**
**True** - states variables are not unfixed, and a dict of
returned containing flags for which states were fixed
during initialization, **False** - state variables are
unfixed after initialization by calling the release_state
method.
Returns:
If hold_states is True, returns a dict containing flags for which
states were fixed during initialization.
'''
# Set solver options
if outlvl > 1:
stee = True
else:
stee = False
opt = SolverFactory(solver)
opt.options = optarg
# Initialize mixed state block
if blk.config.mixed_state_block is not None:
mblock = blk.config.mixed_state_block
else:
mblock = blk.mixed_state
flags = mblock.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
hold_state=True)
if blk.config.ideal_separation:
# If using ideal splitting, initialisation should be complete
return flags
# Initialize outlet StateBlocks
outlet_list = blk.create_outlet_list()
for o in outlet_list:
# Get corresponding outlet StateBlock
o_block = getattr(blk, o + "_state")
for t in blk.flowsheet().config.time:
# Calculate values for state variables
s_vars = o_block[t].define_state_vars()
for v in s_vars:
m_var = getattr(mblock[t], s_vars[v].local_name)
if "flow" in v:
# If a "flow" variable, is extensive
# Apply split fraction
try:
for k in s_vars[v]:
if (k is None or blk.config.split_basis
== SplittingType.totalFlow):
s_vars[v][k].value = value(
m_var[k] * blk.split_fraction[(t, o)])
else:
s_vars[v][k].value = value(
m_var[k] *
blk.split_fraction[(t, o) + k])
except KeyError:
raise KeyError(
"{} state variable and split fraction "
"indexing sets do not match. The in-built"
" initialization routine for Separators "
"relies on the split fraction and state "
"variable indexing sets matching to "
"calculate initial guesses for extensive "
"variables. In other cases users will "
"need to provide their own initial "
"guesses".format(blk.name))
else:
# Otherwise intensive, equate to mixed stream
for k in s_vars[v]:
s_vars[v][k].value = m_var[k].value
# Call initialization routine for outlet StateBlock
o_block.initialize(outlvl=outlvl - 1,
optarg=optarg,
solver=solver,
hold_state=False)
if blk.config.mixed_state_block is None:
results = opt.solve(blk, tee=stee)
if outlvl > 0:
if results.solver.termination_condition == \
TerminationCondition.optimal:
_log.info('{} Initialisation Complete.'.format(blk.name))
else:
_log.warning('{} Initialisation Failed.'.format(blk.name))
else:
_log.info('{} Initialisation Complete.'.format(blk.name))
if hold_state is True:
return flags
else:
blk.release_state(flags, outlvl=outlvl - 1)
def initialize(blk, state_args_feedwater={}, state_args_water_steam={},
outlvl=idaeslog.NOTSET, solver='ipopt', optarg={'tol': 1e-6}):
'''
Drum initialization routine.
Keyword Arguments:
state_args : a dict of arguments to be passed to the property
package(s) for the control_volume of the model to
provide an initial state for initialization
(see documentation of the specific property package)
(default = None).
outlvl : sets output level of initialisation routine
* 0 = no output (default)
* 1 = return solver state for each step in routine
* 2 = return solver state for each step in subroutines
* 3 = include solver output infomation (tee=True)
optarg : solver options dictionary object (default={'tol': 1e-6})
solver : str indicating whcih solver to use during
initialization (default = 'ipopt')
Returns:
None
'''
init_log = idaeslog.getInitLogger(blk.name, outlvl, tag="unit")
solve_log = idaeslog.getSolveLogger(blk.name, outlvl, tag="unit")
opt = SolverFactory(solver)
opt.options = optarg
init_log.info_low("Starting initialization...")
# fix FeedWater Inlet
flags_fw = fix_state_vars(blk.mixer.FeedWater_state,
state_args_feedwater)
# expecting 2 DOF due to pressure driven constraint
if degrees_of_freedom(blk) != 2:
raise Exception(degrees_of_freedom(blk))
blk.flash.initialize(state_args_water_steam=state_args_water_steam,
outlvl=outlvl,
optarg=optarg,
solver=solver)
init_log.info("Initialization Step 1 Complete.")
blk.mixer.SaturatedWater.flow_mol[:].fix(blk.flash.liq_outlet.
flow_mol[0].value)
blk.mixer.SaturatedWater.pressure[:].fix(blk.flash.liq_outlet.
pressure[0].value)
blk.mixer.SaturatedWater.enth_mol[:].fix(blk.flash.liq_outlet.
enth_mol[0].value)
blk.mixer.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver)
init_log.info("Initialization Step 2 Complete.")
blk.control_volume.initialize(outlvl=outlvl,
optarg=optarg,
solver=solver,
hold_state=False)
init_log.info("Initialization Step 3 Complete.")
# fix flash Inlet
flags_steam = fix_state_vars(blk.flash.mixed_state,
state_args_water_steam)
# unfix inlets (connected with arc)
blk.mixer.SaturatedWater.flow_mol[:].unfix()
blk.mixer.SaturatedWater.enth_mol[:].unfix()
blk.mixer.SaturatedWater.pressure[:].unfix()
blk.mixer.FeedWater.pressure[0].unfix()
# solve model
with idaeslog.solver_log(solve_log, idaeslog.DEBUG) as slc:
res = opt.solve(blk, tee=slc.tee)
init_log.info_high(
"Initialization Step 4 {}.".format(idaeslog.condition(res))
)
revert_state_vars(blk.mixer.FeedWater_state, flags_fw)
revert_state_vars(blk.flash.mixed_state, flags_steam)
init_log.info("Initialization Complete.")
