Ejemplo n.º 1
0
class FWH0DData(UnitModelBlockData):
    CONFIG = UnitModelBlockData.CONFIG()
    _define_feedwater_heater_0D_config(CONFIG)

    def build(self):
        super().build()
        config = self.config  # sorter ref to config for less line splitting

        # All feedwater heaters have a condensing section
        _set_prop_pack(config.condense, config)
        self.condense = FWHCondensing0D(default=config.condense)

        # Add a mixer to add the drain stream from another feedwater heater
        if config.has_drain_mixer:
            mix_cfg = {  # general unit model config
                "dynamic": config.dynamic,
                "has_holdup": config.has_holdup,
                "property_package": config.property_package,
                "property_package_args": config.property_package_args,
                "momentum_mixing_type": MomentumMixingType.none,
                "material_balance_type": MaterialBalanceType.componentTotal,
                "inlet_list": ["steam", "drain"]
            }
            self.drain_mix = Mixer(default=mix_cfg)

            @self.drain_mix.Constraint(self.drain_mix.flowsheet().config.time)
            def mixer_pressure_constraint(b, t):
                """
                Constraint to set the drain mixer pressure to the pressure of
                the steam extracted from the turbine. The drain inlet should
                always be a higher pressure than the steam inlet.
                """
                return b.steam_state[t].pressure == b.mixed_state[t].pressure

            # Connect the mixer to the condensing section inlet
            self.mix_out_arc = Arc(source=self.drain_mix.outlet,
                                   destination=self.condense.inlet_1)

        # Add a desuperheat section before the condensing section
        if config.has_desuperheat:
            _set_prop_pack(config.desuperheat, config)
            self.desuperheat = HeatExchanger(default=config.desuperheat)
            # set default area less than condensing section area, this will
            # almost always be overridden by the user fixing an area later
            self.desuperheat.area.value = 10
            if config.has_drain_mixer:
                self.desuperheat_drain_arc = Arc(
                    source=self.desuperheat.outlet_1,
                    destination=self.drain_mix.steam)
            else:
                self.desuperheat_drain_arc = Arc(
                    source=self.desuperheat.outlet_1,
                    destination=self.condense.inlet_1)
            self.condense_out2_arc = Arc(source=self.condense.outlet_2,
                                         destination=self.desuperheat.inlet_2)

        # Add a drain cooling section after the condensing section
        if config.has_drain_cooling:
            _set_prop_pack(config.cooling, config)
            self.cooling = HeatExchanger(default=config.cooling)
            # set default area less than condensing section area, this will
            # almost always be overridden by the user fixing an area later
            self.cooling.area.value = 10
            self.cooling_out2_arc = Arc(source=self.cooling.outlet_2,
                                        destination=self.condense.inlet_2)
            self.condense_out1_arc = Arc(source=self.condense.outlet_1,
                                         destination=self.cooling.inlet_1)

        TransformationFactory("network.expand_arcs").apply_to(self)

    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)
Ejemplo n.º 2
0
class TurbineMultistageData(UnitModelBlockData):

    CONFIG = ConfigBlock()
    _define_turbine_multistage_config(CONFIG)

    def build(self):
        super(TurbineMultistageData, self).build()
        config = self.config
        unit_cfg = { # general unit model config
            "dynamic":config.dynamic,
            "has_holdup":config.has_holdup,
            "has_phase_equilibrium":config.has_phase_equilibrium,
            "property_package":config.property_package,
            "property_package_args":config.property_package_args,
        }
        ni = self.config.num_parallel_inlet_stages
        inlet_idx = self.inlet_stage_idx = RangeSet(ni)

        # Adding unit models
        #------------------------

        # Splitter to inlet that splits main flow into parallel flows for
        # paritial arc admission to the turbine
        self.inlet_split = Separator(default=self._split_cfg(unit_cfg, ni))
        self.throttle_valve = SteamValve(inlet_idx, default=unit_cfg)
        self.inlet_stage = TurbineInletStage(inlet_idx, default=unit_cfg)
        # mixer to combine the parallel flows back together
        self.inlet_mix = Mixer(default=self._mix_cfg(unit_cfg, ni))
        # add turbine sections.
        # inlet stage -> hp stages -> ip stages -> lp stages -> outlet stage
        self.hp_stages = TurbineStage(RangeSet(config.num_hp),
                                      default=unit_cfg)
        self.ip_stages = TurbineStage(RangeSet(config.num_ip),
                                      default=unit_cfg)
        self.lp_stages = TurbineStage(RangeSet(config.num_lp),
                                      default=unit_cfg)
        self.outlet_stage = TurbineOutletStage(default=unit_cfg)

        for i in self.hp_stages:
            self.hp_stages[i].ratioP.fix()
            self.hp_stages[i].efficiency_isentropic[:].fix()
        for i in self.ip_stages:
            self.ip_stages[i].ratioP.fix()
            self.ip_stages[i].efficiency_isentropic[:].fix()
        for i in self.lp_stages:
            self.lp_stages[i].ratioP.fix()
            self.lp_stages[i].efficiency_isentropic[:].fix()

        # Then make splitter config.  If number of outlets is specified
        # make a specific config, otherwise use default with 2 outlets
        s_sfg_default = self._split_cfg(unit_cfg, 2)
        hp_splt_cfg = {}
        ip_splt_cfg = {}
        lp_splt_cfg = {}
        # Now to finish up if there are more than two outlets, set that
        for i, v in config.hp_split_num_outlets.items():
            hp_splt_cfg[i] = self._split_cfg(unit_cfg, v)
        for i, v in config.ip_split_num_outlets.items():
            ip_splt_cfg[i] = self._split_cfg(unit_cfg, v)
        for i, v in config.lp_split_num_outlets.items():
            lp_splt_cfg[i] = self._split_cfg(unit_cfg, v)
        # put in splitters for turbine steam extractions
        if config.hp_split_locations:
            self.hp_split = Separator(config.hp_split_locations,
                                      default=s_sfg_default,
                                      initialize=hp_splt_cfg)
        if config.ip_split_locations:
            self.ip_split = Separator(config.ip_split_locations,
                                      default=s_sfg_default,
                                      initialize=ip_splt_cfg)
        if config.lp_split_locations:
            self.lp_split = Separator(config.lp_split_locations,
                                      default=s_sfg_default,
                                      initialize=lp_splt_cfg)

        # Done with unit models.  Adding Arcs (streams).
        #------------------------------------------------

        # First up add streams in the inlet section
        def _split_to_rule(b, i):
            return {
                "source": getattr(self.inlet_split, "outlet_{}".format(i)),
                "destination": self.throttle_valve[i].inlet
            }

        def _valve_to_rule(b, i):
            return {
                "source": self.throttle_valve[i].outlet,
                "destination": self.inlet_stage[i].inlet
            }

        def _inlet_to_rule(b, i):
            return {
                "source": self.inlet_stage[i].outlet,
                "destination": getattr(self.inlet_mix, "inlet_{}".format(i))
            }

        self.split_to_valve_stream = Arc(inlet_idx, rule=_split_to_rule)
        self.valve_to_inlet_stage_stream = Arc(inlet_idx, rule=_valve_to_rule)
        self.inlet_stage_to_mix = Arc(inlet_idx, rule=_inlet_to_rule)

        # There are three sections HP, IP, and LP which all have the same sort
        # of internal connctions, so the functions below provide some generic
        # capcbilities for adding the internal Arcs (streams).
        def _arc_indexes(nstages, index_set, discon, splits):
            """
            This takes the index set of all possible streams in a turbine
            section and throws out arc indexes for stages that are disconnected
            and arc indexes that are not needed because there is no splitter
            after a stage.

            Args:
                nstages (int): Number of stages in section
                index_set (Set): Index set for arcs in the section
                discon (list): Disconnected stages in the section
                splits (list): Spliter locations
            """
            sr = set()  # set of things to remove from the Arc index set
            for i in index_set:
                if (i[0] in discon or i[0] == nstages) and i[0] in splits:
                    # don't connect stage i to next remove stream after split
                    sr.add((i[0], 2))
                elif (i[0] in discon
                      or i[0] == nstages) and i[0] not in splits:
                    # no splitter and disconnect so remove both streams
                    sr.add((i[0], 1))
                    sr.add((i[0], 2))
                elif i[0] not in splits:
                    # no splitter and not disconnected so just second stream
                    sr.add((i[0], 2))
                else:
                    # has splitter so need both streams don't remove anything
                    pass
            for i in sr:  # remove the unneeded Arc indexes
                index_set.remove(i)

        def _arc_rule(turbines, splitters):
            """
            This creates a rule function for arcs in a turbine section. When
            this is used the indexes for nonexistant stream will have already
            been removed, so any indexes the rule will get should have a stream
            associated.

            Args:
                turbines (TurbineStage): Indexed block with turbine section stages
                splitters (Separator): Indexed block of splitters
            """
            def _rule(b, i, j):
                if i in splitters and j == 1:
                    return {
                        "source": turbines[i].outlet,
                        "destination": splitters[i].inlet
                    }
                elif j == 2:
                    return {
                        "source": splitters[i].outlet_1,
                        "destination": turbines[i + 1].inlet
                    }
                else:
                    return {
                        "source": turbines[i].outlet,
                        "destination": turbines[i + 1].inlet
                    }

            return _rule

        # Create initial arcs index sets with all possible streams
        self.hp_stream_idx = Set(initialize=self.hp_stages.index_set() *
                                 [1, 2])
        self.ip_stream_idx = Set(initialize=self.ip_stages.index_set() *
                                 [1, 2])
        self.lp_stream_idx = Set(initialize=self.lp_stages.index_set() *
                                 [1, 2])

        # Throw out unneeded streams
        _arc_indexes(config.num_hp, self.hp_stream_idx, config.hp_disconnect,
                     config.hp_split_locations)
        _arc_indexes(config.num_ip, self.ip_stream_idx, config.ip_disconnect,
                     config.ip_split_locations)
        _arc_indexes(config.num_lp, self.lp_stream_idx, config.lp_disconnect,
                     config.lp_split_locations)

        # Create connections internal to each turbine section (hp, ip, and lp)
        self.hp_stream = Arc(self.hp_stream_idx,
                             rule=_arc_rule(self.hp_stages, self.hp_split))
        self.ip_stream = Arc(self.ip_stream_idx,
                             rule=_arc_rule(self.ip_stages, self.ip_split))
        self.lp_stream = Arc(self.lp_stream_idx,
                             rule=_arc_rule(self.lp_stages, self.lp_split))

        # Connect hp section to ip section unless its a disconnect location
        last_hp = config.num_hp
        if 0 not in config.ip_disconnect and last_hp not in config.hp_disconnect:
            if last_hp in config.hp_split_locations:  # connect splitter to ip
                self.hp_to_ip_stream = Arc(
                    source=self.hp_split[last_hp].outlet_1,
                    destination=self.ip_stages[1].inlet)
            else:  # connect last hp to ip
                self.hp_to_ip_stream = Arc(
                    source=self.hp_stages[last_hp].outlet,
                    destination=self.ip_stages[1].inlet)
        # Connect ip section to lp section unless its a disconnect location
        last_ip = config.num_ip
        if 0 not in config.lp_disconnect and last_ip not in config.ip_disconnect:
            if last_ip in config.ip_split_locations:  # connect splitter to ip
                self.ip_to_lp_stream = Arc(
                    source=self.ip_split[last_ip].outlet_1,
                    destination=self.lp_stages[1].inlet)
            else:  # connect last hp to ip
                self.ip_to_lp_stream = Arc(
                    source=self.ip_stages[last_ip].outlet,
                    destination=self.lp_stages[1].inlet)
        # Connect inlet stage to hp section
        #   not allowing disconnection of inlet and first regular hp stage
        if 0 in config.hp_split_locations:
            # connect inlet mix to splitter and splitter to hp section
            self.inlet_to_splitter_stream = Arc(
                source=self.inlet_mix.outlet,
                destination=self.hp_split[0].inlet)
            self.splitter_to_hp_stream = Arc(
                source=self.hp_split[0].outlet_1,
                destination=self.hp_stages[1].inlet)
        else:  # connect mixer to first hp turbine stage
            self.inlet_to_hp_stream = Arc(source=self.inlet_mix.outlet,
                                          destination=self.hp_stages[1].inlet)

        @self.Expression(self.flowsheet().config.time)
        def power(b, t):
            return (sum(b.inlet_stage[i].power_shaft[t]
                        for i in b.inlet_stage) +
                    b.outlet_stage.power_shaft[t] +
                    sum(b.hp_stages[i].power_shaft[t] for i in b.hp_stages) +
                    sum(b.ip_stages[i].power_shaft[t] for i in b.ip_stages) +
                    sum(b.lp_stages[i].power_shaft[t] for i in b.lp_stages))

        # Connect inlet stage to hp section
        #   not allowing disconnection of inlet and first regular hp stage
        last_lp = config.num_lp
        if last_lp in config.lp_split_locations:  # connect splitter to outlet
            self.lp_to_outlet_stream = Arc(
                source=self.lp_split[last_lp].outlet_1,
                destination=self.outlet_stage.inlet)
        else:  # connect last lpstage to outlet
            self.lp_to_outlet_stream = Arc(
                source=self.lp_stages[last_lp].outlet,
                destination=self.outlet_stage.inlet)
        TransformationFactory("network.expand_arcs").apply_to(self)

    def _split_cfg(self, unit_cfg, no=2):
        """
        This creates a configuration dictionary for a splitter.

        Args:
            unit_cfg: The base unit config dict.
            no: Number of outlets, default=2
        """
        # Create a dict for splitter config args
        s_cfg = copy.copy(unit_cfg)  # splitter config based on unit_cfg
        s_cfg.update(
            split_basis=SplittingType.totalFlow,
            ideal_separation=False,
            num_outlets=no,
            energy_split_basis=EnergySplittingType.equal_molar_enthalpy)
        del s_cfg["has_phase_equilibrium"]
        return s_cfg

    def _mix_cfg(self, unit_cfg, ni=2):
        """
        This creates a configuration dictionary for a mixer.

        Args:
            unit_cfg: The base unit config dict.
            ni: Number of inlets, default=2
        """
        m_cfg = copy.copy(unit_cfg)  # splitter config based on unit_cfg
        m_cfg.update(
            num_inlets=ni,
            momentum_mixing_type=MomentumMixingType.minimize_and_equality)
        del m_cfg["has_phase_equilibrium"]
        return m_cfg

    def throttle_cv_fix(self, value):
        """
        Fix the thottle valve coefficients.  These are generally the same for
        each of the parallel stages so this provides a convenient way to set
        them.

        Args:
            value: The value to fix the turbine inlet flow coefficients at
        """
        for i in self.throttle_valve:
            self.throttle_valve[i].Cv.fix(value)

    def turbine_inlet_cf_fix(self, value):
        """
        Fix the inlet turbine stage flow coefficient.  These are
        generally the same for each of the parallel stages so this provides
        a convenient way to set them.

        Args:
            value: The value to fix the turbine inlet flow coefficients at
        """
        for i in self.inlet_stage:
            self.inlet_stage[i].flow_coeff.fix(value)

    def turbine_outlet_cf_fix(self, value):
        """
        Fix the inlet turbine stage flow coefficient.  These are
        generally the same for each of the parallel stages so this provides
        a convenient way to set them.

        Args:
            value: The value to fix the turbine inlet flow coefficients at
        """
        self.outlet_stage.flow_coeff.fix(value)

    def initialize(self,
                   outlvl=0,
                   solver='ipopt',
                   optarg={
                       'tol': 1e-6,
                       'max_iter': 35
                   }):
        """
        Initialize
        """
        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)

        ni = self.config.num_parallel_inlet_stages

        # Initialize Splitter
        # Fix n - 1 split fractions
        self.inlet_split.split_fraction[0, "outlet_1"].value = 1.0 / ni
        for i in self.inlet_stage_idx:
            if i == 1:  #fix rest of splits at leaving first one free
                continue
            self.inlet_split.split_fraction[0, "outlet_{}".format(i)].fix(1.0 /
                                                                          ni)
        # fix inlet and free outlet
        self.inlet_split.inlet.fix()
        for i in self.inlet_stage_idx:
            ol = getattr(self.inlet_split, "outlet_{}".format(i))
            ol.unfix()
        self.inlet_split.initialize(outlvl=outlvl,
                                    solver=solver,
                                    optarg=optarg)
        # free split fractions
        for i in self.inlet_stage_idx:
            self.inlet_split.split_fraction[0, "outlet_{}".format(i)].unfix()

        # Initialize valves
        for i in self.inlet_stage_idx:
            _set_port(self.throttle_valve[i].inlet,
                      getattr(self.inlet_split, "outlet_{}".format(i)))
            self.throttle_valve[i].initialize(outlvl=outlvl,
                                              solver=solver,
                                              optarg=optarg)

        # Initialize turbine
        for i in self.inlet_stage_idx:
            _set_port(self.inlet_stage[i].inlet, self.throttle_valve[i].outlet)
            self.inlet_stage[i].initialize(outlvl=outlvl,
                                           solver=solver,
                                           optarg=optarg)

        # Initialize Mixer
        self.inlet_mix.use_minimum_inlet_pressure_constraint()
        for i in self.inlet_stage_idx:
            _set_port(getattr(self.inlet_mix, "inlet_{}".format(i)),
                      self.inlet_stage[i].outlet)
            getattr(self.inlet_mix, "inlet_{}".format(i)).fix()
        self.inlet_mix.initialize(outlvl=outlvl, solver=solver, optarg=optarg)
        for i in self.inlet_stage_idx:
            getattr(self.inlet_mix, "inlet_{}".format(i)).unfix()
        self.inlet_mix.use_equal_pressure_constraint()

        def init_section(stages, splits, disconnects, prev_port):
            if 0 in splits:
                _set_port(splits[0].inlet, prev_port)
                splits[0].initialize(outlvl=outlvl,
                                     solver=solver,
                                     optarg=optarg)
                prev_port = splits[0].outlet_1
            for i in stages:
                if i - 1 not in disconnects:
                    _set_port(stages[i].inlet, prev_port)
                stages[i].initialize(outlvl=outlvl,
                                     solver=solver,
                                     optarg=optarg)
                prev_port = stages[i].outlet
                if i in splits:
                    _set_port(splits[i].inlet, prev_port)
                    splits[i].initialize(outlvl=outlvl,
                                         solver=solver,
                                         optarg=optarg)
                    prev_port = splits[i].outlet_1
            return prev_port

        prev_port = self.inlet_mix.outlet
        prev_port = init_section(self.hp_stages, self.hp_split,
                                 self.config.hp_disconnect, prev_port)
        if len(self.hp_stages) in self.config.hp_disconnect:
            prev_port = self.ip_stages[1].inlet
        prev_port = init_section(self.ip_stages, self.ip_split,
                                 self.config.ip_disconnect, prev_port)
        if len(self.ip_stages) in self.config.ip_disconnect:
            prev_port = self.lp_stages[1].inlet
        prev_port = init_section(self.lp_stages, self.lp_split,
                                 self.config.lp_disconnect, prev_port)

        _set_port(self.outlet_stage.inlet, prev_port)
        self.outlet_stage.initialize(outlvl=outlvl,
                                     solver=solver,
                                     optarg=optarg)

        from_json(self, sd=istate, wts=sp)