Source code for tespy.components.nodes.droplet_separator

# -*- coding: utf-8

"""Module of class DropletSeparator.


This file is part of project TESPy (github.com/oemof/tespy). It's copyrighted
by the contributors recorded in the version control history of the file,
available from its original location
tespy/components/nodes/droplet_separator.py

SPDX-License-Identifier: MIT
"""

from tespy.components.component import component_registry
from tespy.components.nodes.base import NodeBase
from tespy.tools.document_models import generate_latex_eq
from tespy.tools.fluid_properties import dh_mix_dpQ
from tespy.tools.fluid_properties import h_mix_pQ


[docs] @component_registry class DropletSeparator(NodeBase): r""" Separate liquid phase from gas phase of a single fluid. This component is the parent component of the Drum. **Mandatory Equations** - :py:meth:`tespy.components.nodes.base.NodeBase.mass_flow_func` - :py:meth:`tespy.components.nodes.base.NodeBase.pressure_equality_func` - :py:meth:`tespy.components.nodes.droplet_separator.DropletSeparator.fluid_func` - :py:meth:`tespy.components.nodes.droplet_separator.DropletSeparator.energy_balance_func` - :py:meth:`tespy.components.nodes.droplet_separator.DropletSeparator.outlet_states_func` Inlets/Outlets - in1 - out1, out2 (index 1: saturated liquid, index 2: saturated gas) Image .. image:: /api/_images/DropletSeparator.svg :alt: flowsheet of the droplet separator :align: center :class: only-light .. image:: /api/_images/DropletSeparator_darkmode.svg :alt: flowsheet of the droplet separator :align: center :class: only-dark Parameters ---------- label : str The label of the component. design : list List containing design parameters (stated as String). offdesign : list List containing offdesign parameters (stated as String). design_path : str Path to the components design case. local_offdesign : boolean Treat this component in offdesign mode in a design calculation. local_design : boolean Treat this component in design mode in an offdesign calculation. char_warnings : boolean Ignore warnings on default characteristics usage for this component. printout : boolean Include this component in the network's results printout. Example ------- The droplet separator separates gas from liquid phase. From a stream of water the liquid phase will be separated. >>> from tespy.components import Sink, Source, DropletSeparator >>> from tespy.connections import Connection >>> from tespy.networks import Network >>> import shutil >>> nw = Network(T_unit='C', p_unit='bar', h_unit='kJ / kg', iterinfo=False) >>> so = Source('two phase inflow') >>> sig = Sink('gas outflow') >>> sil = Sink('liquid outflow') >>> ds = DropletSeparator('droplet separator') >>> ds.component() 'droplet separator' >>> so_ds = Connection(so, 'out1', ds, 'in1') >>> ds_sig = Connection(ds, 'out2', sig, 'in1') >>> ds_sil = Connection(ds, 'out1', sil, 'in1') >>> nw.add_conns(so_ds, ds_sig, ds_sil) We specify the fluid's state at the inlet. At the gas outflow saturated gas enthalpy is expected, at the liquid gas outflow saturated liquid enthalpy. The mass flow at the outlets is expected to split according to the vapor mass fraction: .. math:: \dot{m}_\mathrm{out,1} = \left(1 - \frac{h_\mathrm{in} - h'}{h'' - h'} \right) \cdot \dot{m}_\mathrm{in} \dot{m}_\mathrm{out,2} = \frac{h_\mathrm{in} - h'}{h'' - h'} \cdot \dot{m}_\mathrm{in} >>> so_ds.set_attr(fluid={'water': 1}, p=1, h=1500, m=10) >>> nw.solve('design') >>> Q_in = so_ds.calc_Q() >>> round(Q_in * so_ds.m.val_SI, 6) == round(ds_sig.m.val_SI, 6) True >>> round((1 - Q_in) * so_ds.m.val_SI, 6) == round(ds_sil.m.val_SI, 6) True >>> ds_sig.calc_Q() 1.0 >>> ds_sil.calc_Q() 0.0 In a different setup, we unset pressure and enthalpy and specify gas temperature and mass flow instead. The temperature specification must yield the corresponding boiling point pressure and the mass flow must yield the inlet enthalpy. The inlet vapor mass fraction must be equal to fraction of gas mass flow to inlet mass flow (0.95 in this example). >>> so_ds.set_attr(fluid={'water': 1}, p=None, h=None, T=150, m=10) >>> ds_sig.set_attr(m=9.5) >>> nw.solve('design') >>> round(so_ds.calc_Q(), 6) 0.95 >>> T_boil = so_ds.calc_T_sat() >>> round(T_boil, 6) == round(so_ds.T.val_SI, 6) True """
[docs] @staticmethod def component(): return 'droplet separator'
[docs] def get_mandatory_constraints(self): return { 'mass_flow_constraints': { 'func': self.mass_flow_func, 'deriv': self.mass_flow_deriv, 'constant_deriv': True, 'latex': self.mass_flow_func_doc, 'num_eq': 1}, 'energy_balance_constraints': { 'func': self.energy_balance_func, 'deriv': self.energy_balance_deriv, 'constant_deriv': False, 'latex': self.energy_balance_func_doc, 'num_eq': 1}, 'pressure_constraints': { 'func': self.pressure_equality_func, 'deriv': self.pressure_equality_deriv, 'constant_deriv': True, 'latex': self.pressure_equality_func_doc, 'num_eq': self.num_i + self.num_o - 1}, 'outlet_constraints': { 'func': self.outlet_states_func, 'deriv': self.outlet_states_deriv, 'constant_deriv': False, 'latex': self.outlet_states_func_doc, 'num_eq': 2} }
[docs] @staticmethod def inlets(): return ['in1']
[docs] @staticmethod def outlets(): return ['out1', 'out2']
[docs] def energy_balance_func(self): r""" Calculate energy balance. Returns ------- residual : float Residual value of energy balance. .. math:: 0 = \sum_i \left(\dot{m}_{in,i} \cdot h_{in,i} \right) - \sum_j \left(\dot{m}_{out,j} \cdot h_{out,j} \right)\\ \forall i \in \text{inlets} \; \forall j \in \text{outlets} """ res = 0 for i in self.inl: res += i.m.val_SI * i.h.val_SI for o in self.outl: res -= o.m.val_SI * o.h.val_SI return res
[docs] def energy_balance_func_doc(self, label): r""" Calculate energy balance. Parameters ---------- label : str Label for equation. Returns ------- latex : str LaTeX code of equations applied. """ latex = ( r'0=\sum_i\left(\dot{m}_{\mathrm{in,}i}\cdot h_{\mathrm{in,}i}' r'\right) - \sum_j \left(\dot{m}_{\mathrm{out,}j} \cdot ' r'h_{\mathrm{out,}j} \right) \; \forall i \in \text{inlets} \;' r'\forall j \in \text{outlets}' ) return generate_latex_eq(self, latex, label)
[docs] def energy_balance_deriv(self, increment_filter, k): r""" Calculate partial derivatives of energy balance. Parameters ---------- increment_filter : ndarray Matrix for filtering non-changing variables. k : int Position of derivatives in Jacobian matrix (k-th equation). """ for i in self.inl: if i.m.is_var: self.jacobian[k, i.m.J_col] = i.h.val_SI if i.h.is_var: self.jacobian[k, i.h.J_col] = i.m.val_SI for o in self.outl: if o.m.is_var: self.jacobian[k, o.m.J_col] = -o.h.val_SI if o.h.is_var: self.jacobian[k, o.h.J_col] = -o.m.val_SI
[docs] def outlet_states_func(self): r""" Calculate energy balance. Returns ------- residual : list Residual values of outlet state equations. .. math:: 0 = h_{out,1} - h\left(p, x=0 \right)\\ 0 = h_{out,2} - h\left(p, x=1 \right) """ o0 = self.outl[0] o1 = self.outl[1] return [ h_mix_pQ(o0.p.val_SI, 0, o0.fluid_data) - o0.h.val_SI, h_mix_pQ(o1.p.val_SI, 1, o1.fluid_data) - o1.h.val_SI ]
[docs] def outlet_states_func_doc(self, label): r""" Calculate energy balance. Parameters ---------- label : str Label for equation. Returns ------- latex : str LaTeX code of equations applied. """ latex = ( r'\begin{split}' + '\n' r'0 =&h_\mathrm{out,1} -h\left(p_\mathrm{out,1}, x=0\right)\\' r'0 =&h_\mathrm{out,2} -h\left(p_\mathrm{out,2}, x=1\right)\\' r'\end{split}' ) return generate_latex_eq(self, latex, label)
[docs] def outlet_states_deriv(self, increment_filter, k): r""" Calculate partial derivatives of outlet states. Parameters ---------- increment_filter : ndarray Matrix for filtering non-changing variables. k : int Position of derivatives in Jacobian matrix (k-th equation). """ o0 = self.outl[0] o1 = self.outl[1] if o0.p.is_var: self.jacobian[k, o0.p.J_col] = ( dh_mix_dpQ(o0.p.val_SI, 0, o0.fluid_data) ) if o0.h.is_var and self.it == 0: self.jacobian[k, o0.h.J_col] = -1 if o1.p.is_var: self.jacobian[k + 1, o1.p.J_col] = ( dh_mix_dpQ(o1.p.val_SI, 1, o1.fluid_data) ) if o1.h.is_var and self.it == 0: self.jacobian[k + 1, o1.h.J_col] = -1
[docs] def propagate_wrapper_to_target(self, branch): if self in branch["components"]: return for outconn in self.outl: branch["connections"] += [outconn] branch["components"] += [self] outconn.target.propagate_wrapper_to_target(branch)
[docs] @staticmethod def initialise_source(c, key): r""" Return a starting value for pressure and enthalpy at outlet. Parameters ---------- c : tespy.connections.connection.Connection Connection to perform initialisation on. key : str Fluid property to retrieve. Returns ------- val : float Starting value for pressure/enthalpy in SI units. .. math:: val = \begin{cases} 10^6 & \text{key = 'p'}\\ h\left(p, x=1 \right) & \text{key = 'h' at outlet 1}\\ h\left(p, x=0 \right) & \text{key = 'h' at outlet 2} \end{cases} """ if key == 'p': return 10e5 elif key == 'h': if c.source_id == 'out1': return h_mix_pQ(c.p.val_SI, 0, c.fluid_data) else: return h_mix_pQ(c.p.val_SI, 1, c.fluid_data)
[docs] @staticmethod def initialise_target(c, key): r""" Return a starting value for pressure and enthalpy at inlet. Parameters ---------- c : tespy.connections.connection.Connection Connection to perform initialisation on. key : str Fluid property to retrieve. Returns ------- val : float Starting value for pressure/enthalpy in SI units. .. math:: val = \begin{cases} 10^6 & \text{key = 'p'}\\ h\left(p, x=0.5 \right) & \text{key = 'h' at inlet 1} \end{cases} """ if key == 'p': return 10e5 elif key == 'h': return h_mix_pQ(c.p.val_SI, 0.5, c.fluid_data)
[docs] def get_plotting_data(self): """Generate a dictionary containing FluProDia plotting information. Returns ------- data : dict A nested dictionary containing the keywords required by the :code:`calc_individual_isoline` method of the :code:`FluidPropertyDiagram` class. First level keys are the connection index ('in1' -> 'out1', therefore :code:`1` etc.). """ return { i + 1: { 'isoline_property': 'p', 'isoline_value': self.inl[0].p.val, 'isoline_value_end': self.outl[i].p.val, 'starting_point_property': 'v', 'starting_point_value': self.inl[0].vol.val, 'ending_point_property': 'v', 'ending_point_value': self.outl[i].vol.val } for i in range(2)}