PooPyLab.unit_procs.streams.splitter Class Reference

Stream element with an inlet, a mainstream outlet, and a sidestream outlet. More...

Inheritance diagram for PooPyLab.unit_procs.streams.splitter:

Public Member Functions
def	__init__ (self)
	Constructor for "splitter".
def	set_flow_data_src (self, branch='Main', flow_ds=flow_data_src.TBD)
	Set the flow data source of the branch specified by the user. More...
def	get_flow_data_src (self)
	Return the flow data source tags of all three branches.
def	assign_initial_guess (self, init_guess_lst)
	Assign the intial guess to the unit before simulation. More...
def	is_converged (self, limit=1E-6)
	Return the convergence status of the unit. More...
def	get_type (self)
	Return the type string of the process unit. More...
def	has_sidestream (self)
	Return whether the unit has a sidestream. More...
def	add_upstream (self, discharger, upst_branch='Main')
	Add the discharger's branch to inlet. More...
def	has_discharger (self)
	Return whether the unit's inlet has been connected. More...
def	get_upstream (self)
	Return the _inlet {} of the unit. More...
def	totalize_inflow (self)
	Combine the individual flows specified in the self._inlet into one. More...
def	blend_inlet_comps (self)
	Calculate the flow weighted average model component concentrations. More...
def	update_combined_input (self)
	Update both total inflow and blended concentrations (model components).
def	remove_upstream (self, discharger)
	Remove an existing discharger from inlet. More...
def	set_downstream_main (self, rcvr)
	Define the main outlet by specifying the receiving process unit.
def	main_outlet_connected (self)
	Return whether the mainstream outlet is connected. More...
def	get_downstream_main (self)
	Return the process unit connected at the mainstream outlet. More...
def	set_mainstream_flow_by_upstream (self, f=True)
	Set whether the mainstream flow = (total inflow - side outflow).
def	set_mainstream_flow (self, flow=0)
	Define the mainstream outlet flow. More...
def	get_main_outflow (self)
	Return the mainstream outflow. More...
def	get_main_outlet_concs (self)
	Return a copy of the mainstream outlet concentrations. More...
def	set_downstream_side (self, rcvr)
	Define the downstream side outlet's connection. More...
def	side_outlet_connected (self)
	Return True if the main outlet is connected, False if not. More...
def	get_downstream_side (self)
	Return the process unit connected to the side outlet. More...
def	set_sidestream_flow (self, flow=0)
	Define the flow rate for the sidestream. More...
def	sidestream_flow_defined (self)
	Return whether the sidestream flow rate has been defined. More...
def	get_side_outflow (self)
	Return the sidestream outlet flow rate. More...
def	get_side_outlet_concs (self)
	Return a copy of the sidestream outlet concentrations. More...
def	set_flow (self, dschgr, flow)
	Specify the flow from the discharger. More...
def	discharge (self)
	Pass the total flow and blended components to the downstreams. More...
def	get_TSS (self, br='Main')
	Return the Total Suspended Solids of the specified branch.
def	get_VSS (self, br='Main')
	Return the Volatile Suspended Solids of the specified branch.
def	get_COD (self, br='Main')
	Return the Chemical Oxygen Demand (total) of the specified branch.
def	get_sCOD (self, br='Main')
	Return the soluble COD of the specified branch.
def	get_pCOD (self, br='Main')
	Return the particultate COD of the specified branch.
def	get_TN (self, br='Main')
	Return the total nitrogen of the specified branch. More...
def	get_orgN (self, br='Main')
	Return the organic nitrogen of the specified branch.
def	get_inorgN (self, br='Main')
	Return the inorganic nitrogen of the specified branch.
def	get_pN (self, br='Main')
	Return the particulate nitrogen of the specified branch.
def	get_sN (self, br='Main')
	Return the soluble nitrogen of the specified branch.
def	set_as_SRT_controller (self, setting=False)
	Set the current splitter as an Solids Retention Time controller. More...
def	is_SRT_controller (self)
	Return whether a splitter is an SRT controller.

Private Member Functions
def	_discharge_main_outlet (self)
	Pass the flow and concentrations to the main outlet. More...
def	_discharge_side_outlet (self)
	Pass the flow and concentrations to the side outlet. More...
def	_branch_flow_helper (self)
	Calculate 1 of the 3 branches' flow based on the other 2. More...
def	_check_conc_cnvg (self, curr_comps=[], prev_comps=[], abs_lim=1E-6)
	Check the convergence of model components (concentrations). More...
def	_sum_helper (self, branch='Main', index_list=[])
	Sum up the model components indicated by the index_list. More...

Private Attributes
	__name__
	_type
	type string of the process unit
	_inlet
	upstream units and their flows in the format of {unit: Flow}
	_main_outlet
	mainstream outlet, a single receiver
	_side_outlet
	sidestream outlet, a single receiver
	_has_discharger
	flag on whether there are upstream units
	_has_sidestream
	flag on whether there is a sidestream, always True for a splitter
	_mo_connected
	flag on whether the mainstream outlet is connected
	_so_connected
	flag on whether the sidestream outlet is connected
	_upstream_set_mo_flow
	whether the mainstream outflow is by inflow - sidestream outflow
	_in_flow_ds
	flow data source tag for inlet
	_mo_flow_ds
	flow data source tag for mainstream outlet
	_so_flow_ds
	flow data source tag for sidestream outlet
	_so_flow_defined
	flag to confirm it has received _so_flow > 0 m3/d
	_mo_flow
	mainstream outflow, m3/d
	_so_flow
	sidestream outflow, m3/d
	_total_inflow
	total inlet flow, m3/d
	_SRT_controller
	flag on whether this splitter is SRT controller
	_in_comps
	inlet model components
	_mo_comps
	mainstream outlet model components
	_so_comps
	sidestream outlet model components
	_prev_mo_comps
	mainstream outlet model components for the previous round
	_prev_so_comps
	sidestream outlet model components for the previous round
	_converged
	flag on convergence status

Static Private Attributes
int	__id

Detailed Description

Stream element with an inlet, a mainstream outlet, and a sidestream outlet.

There are three connection points for the flows to get in and out of a splitter an inlet, a mainstream outlet, and a sidestream outlet.

General Functions

It is assumed that there is no significant biochemical reactions happening across a splitter unit. It only maintains the flow balance around the three connections. Therefore, the model components (as concentrations) are identical for all the connections after proper flow and load updates.

Flow balance is maintained using the flow data source tags of two of the three connection points (see below for more details).

Special Functions

When specified as an SRT (solids retention time) controller, a splitter would have to be connected with a WAS (waste activated sludge) unit at its sidestream.

Member Function Documentation

set_flow_data_src()

def PooPyLab.unit_procs.streams.splitter.set_flow_data_src	(		self,
			branch = 'Main',
			flow_ds = flow_data_src.TBD
	)

Set the flow data source of the branch specified by the user.

   This function helps to decide how a stream process unit (splitter,
   pipe, influent, effluent, WAS, etc.) performs flow balance
   calculations.

   For instance, if the user defines both the mainstream and sidestream
   outlet flow rates, then the inlet flow rate will be calculated as the
   sum of the two branches. As another example, if the user only defines
   the sidestream branch flow rate, then the mainstream branch flow will
   be determined as (total_inflow - sidestream_outflow).

   When setting the flow data source of a branch, the function will check
   to see whether the flow data sources for the other two brachnes can
   also be determined.

Parameters

branch	'Main'|'Side'|'Inlet'
flow_ds	flow_data_source.TBD|.UPS|.DNS|.PRG

Return

None

See

_branch_flow_helper(),
set_mainstream_flow_by_upstream(),
totalize_inflow(),
utils.flow_data_src.

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

assign_initial_guess()

def PooPyLab.unit_procs.streams.splitter.assign_initial_guess	(		self,
			init_guess_lst
	)

Assign the intial guess to the unit before simulation.

   All three branches of a stream element will get the same model
   components.

Parameters

init_guess_lst

list of model components (concentrations)

Return

None

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.bio.asm_reactor, and PooPyLab.unit_procs.streams.influent.

is_converged()

def PooPyLab.unit_procs.streams.splitter.is_converged	(		self,
			limit = 1E-6
	)

Return the convergence status of the unit.

   This function checks the absolute changes of flows and concentrations
   between last round of simulation and current. If all changes are within
   the tolerance limit, it flags the self._converged True.

   The same absolute changes will be used in evaluting the convergence of
   splitter, clarifier, pipe, effluent, WAS, and other unit processes that
   do not have splicit definitions of change rate terms (dy/dt = f(...)).

   This function is redefined for unit processes like asm_reactor whose
   models have specific dy/dt terms.

Parameters

limit

Limit within which the simulation is considered converged

Return

True/False

See

_check_conc_cnvg()

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent, and PooPyLab.unit_procs.bio.asm_reactor.

get_type()

def PooPyLab.unit_procs.streams.splitter.get_type

(

self

)

Return the type string of the process unit.

Parameters

None

Return

str

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

has_sidestream()

def PooPyLab.unit_procs.streams.splitter.has_sidestream

(

self

)

Return whether the unit has a sidestream.

Parameters

None

Return

bool

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

add_upstream()

def PooPyLab.unit_procs.streams.splitter.add_upstream	(		self,
			discharger,
			upst_branch = 'Main'
	)

Add the discharger's branch to inlet.

   This function add an upstream unit's (discharger's) outlet, as
   specified by the ups_branch parameter, to the current inlet.

   The function first checks whether the specified discharger is already
   in self._inlet. If so, does nothing. Otherwise, add the discharger into
   self._inlet and put 0.0 m3/d as a place holder for the corresponding
   flow rate.

   An error message will display if upst_branch is neither 'Main' nor
   'Side'. And the specified discharger will NOT be added to self._inlet
   as a result.

   After adding the discharger into self._inlet. This function calls the
   discharger's set_downstream_main()/set_downstream_side() to connect its
   mainstream/sidestream outlet to the current unit's inlet.

   Upon sucessful addition of the specified discharger and its branch, the
   self._has_discharger flag is set to True.

Parameters

discharger	the process unit to be added to self._inlet;
upst_branch	branch of the discharger to get flow from.

See

set_downstream_main(),
set_downstream_side(),

remove_upstream().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

has_discharger()

def PooPyLab.unit_procs.streams.splitter.has_discharger

(

self

)

Return whether the unit's inlet has been connected.

Parameters

None

Return

bool

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

get_upstream()

def PooPyLab.unit_procs.streams.splitter.get_upstream

(

self

)

Return the _inlet {} of the unit.

Parameters

None

Return

{unit_addr: flow into self._inlet}

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

totalize_inflow()

def PooPyLab.unit_procs.streams.splitter.totalize_inflow

(

self

)

Combine the individual flows specified in the self._inlet into one.

   There are scenarios to be managed here:

       1) When the mainstream outlet branch's flow is to be calculated
       using the total inflow (self._upstream_set_mo_flow == True): The
       total inflow is calculated using the individual flows specified in
       self._inlet; and

       2) When both flow rates for the mainstream and sidestream outlet
       branches have been specified (either by user or simulation run
       time), i.e. self._upstream_set_mo_flow == False: the total inflow
       will be the sum of the two branches. This calculated total inflow
       is to be passed upstream by the main loop to maintain the WWTP's
       flow balance.

Parameters

None

Return

float

See

utils.datatypes.flow_data_src,
set_flow_data_src(),
set_mainstream_flow_by_upstream(),
_branch_flow_helper(),
blend_inlet_comps(),

update_combined_input().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

blend_inlet_comps()

def PooPyLab.unit_procs.streams.splitter.blend_inlet_comps

(

self

)

Calculate the flow weighted average model component concentrations.

Note

This function does not totalize inlet flow. It only uses the current flow rates. It is adviced to call totalize_inflow() first.

See

totalize_inflow()

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

remove_upstream()

def PooPyLab.unit_procs.streams.splitter.remove_upstream	(		self,
			discharger
	)

Remove an existing discharger from inlet.

   This function first checks whether the specified discharger to be
   removed exists in self._inlet:

       If so, proceed and remove it from self._inlet. Then it finds
       out which branch of the discharger is originally connected to
       current unit's inlet, inform the original discharger to update its
       corresponding branch's connection. The _has_discharger flag will be
       checked and updated when an upstream discharger is removed
       successfully.

       If not, an error message will be displayed and nothing will be
       removed from the self._inlet.

Parameters

discharger

An inlet unit to be removed.

Return

None

See

add_upstream()

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

main_outlet_connected()

def PooPyLab.unit_procs.streams.splitter.main_outlet_connected

(

self

)

Return whether the mainstream outlet is connected.

Parameters

None

Return

bool

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

get_downstream_main()

def PooPyLab.unit_procs.streams.splitter.get_downstream_main

(

self

)

Return the process unit connected at the mainstream outlet.

Parameters

None

Return

poopy_lab_obj

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

set_mainstream_flow()

def PooPyLab.unit_procs.streams.splitter.set_mainstream_flow	(		self,
			flow = 0
	)

Define the mainstream outlet flow.

    If the specified flow is less than 0 m3/d, the current unit's
    mainstream outlet flow will be set to 0 m3/d. An error message will
    display.

    Upon successful setting of the mainstream flow rate, the mainstream
    outlet's flow data source will be set to flow_data_src.PRG, and the
    _upstream_set_mo_flow flag False.

Parameters

flow	flow rate in m3/d, shall be no less than 0.

Return

None

See

set_sidestream_flow(),
totalize_inflow(),

set_flow_data_src().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

get_main_outflow()

def PooPyLab.unit_procs.streams.splitter.get_main_outflow

(

self

)

Return the mainstream outflow.

Parameters

None

Return

float, m3/d

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

get_main_outlet_concs()

def PooPyLab.unit_procs.streams.splitter.get_main_outlet_concs

(

self

)

Return a copy of the mainstream outlet concentrations.

Parameters

None

Return

list

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

set_downstream_side()

def PooPyLab.unit_procs.streams.splitter.set_downstream_side	(		self,
			rcvr
	)

Define the downstream side outlet's connection.

   An influent unit can not receive any flow from the current unit. An
   error message will be displayed if the specified receiver is of the
   influent type.

   If the specified receiver is already connected to the current unit's
   sidestream outlet branch, nothing will be done.

   Successful connection of the receiver and current unit's sidestream
   outlet will set the _so_connected flag to True.

Parameters

rcvr	receiver of the current unit's sidestream outlet flow.

See

add_upstream(),

set_downstream_main().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.pipe.

side_outlet_connected()

def PooPyLab.unit_procs.streams.splitter.side_outlet_connected

(

self

)

Return True if the main outlet is connected, False if not.

Parameters

None

Return

bool

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

get_downstream_side()

def PooPyLab.unit_procs.streams.splitter.get_downstream_side

(

self

)

Return the process unit connected to the side outlet.

Parameters

None

Return

poopy_lab_obj

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

set_sidestream_flow()

def PooPyLab.unit_procs.streams.splitter.set_sidestream_flow	(		self,
			flow = 0
	)

Define the flow rate for the sidestream.

   If the specified flow is less than 0 m3/d, n error message will
   display.

   Upon successful setting of the sidestream flow rate, the sidestream
   outlet's flow data source will be set to flow_data_src.PRG.

Parameters

flow	flow rate in m3/d, shall be no less than 0.

Return

None

See

set_mainstream_flow(),
totalize_inflow(),

set_flow_data_src().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.pipe.

sidestream_flow_defined()

def PooPyLab.unit_procs.streams.splitter.sidestream_flow_defined

(

self

)

Return whether the sidestream flow rate has been defined.

Parameters

None

Return

bool

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

get_side_outflow()

def PooPyLab.unit_procs.streams.splitter.get_side_outflow

(

self

)

Return the sidestream outlet flow rate.

Parameters

None

Return

float

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

get_side_outlet_concs()

def PooPyLab.unit_procs.streams.splitter.get_side_outlet_concs

(

self

)

Return a copy of the sidestream outlet concentrations.

Parameters

None

Return

list

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

set_flow()

def PooPyLab.unit_procs.streams.splitter.set_flow	(		self,
			dschgr,
			flow
	)

Specify the flow from the discharger.

   Please see the _discharge_main_outlet() and _discharge_side_outlet()
   for the use of this function.

Parameters

dschgr	discharger
flow	flow rate in m3/d

Return

None

See

discharge().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.influent.

_discharge_main_outlet()

def PooPyLab.unit_procs.streams.splitter._discharge_main_outlet (   self )

private

Pass the flow and concentrations to the main outlet.

   This function identifies the process unit connected to the mainstream
   outlet, then call its set_flow() and update_combined_input() so that
   the flow and concentrations from the current unit is passed onto the
   mainstream outlet.

See

discharge();
get_downstream_main();
set_flow();
update_combined_input();
_discharge_side_outlet();

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

_discharge_side_outlet()

def PooPyLab.unit_procs.streams.splitter._discharge_side_outlet (   self )

private

Pass the flow and concentrations to the side outlet.

   This function identifies the process unit connected to the sidestream
   outlet, then call its set_flow() and update_combined_input() so that
   the flow and concentrations from the current unit is passed onto the
   sidestream outlet.

See

discharge();
get_downstream_side();
set_flow();
update_combined_input();
_discharge_main_outlet();

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

discharge()

def PooPyLab.unit_procs.streams.splitter.discharge

(

self

)

Pass the total flow and blended components to the downstreams.

   Record the main- and sidestream outlet concentrations from the previous
   iteration. Update the concentrations for the two outlet branches. Pass
   the flows and concentrations onto the downstream units.

See

_branch_flow_helper();
_discharge_main_outlet();

_discharge_side_outlet().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.WAS, PooPyLab.unit_procs.streams.effluent, PooPyLab.unit_procs.streams.influent, and PooPyLab.unit_procs.physchem.final_clarifier.

get_TN()

def PooPyLab.unit_procs.streams.splitter.get_TN	(		self,
			br = 'Main'
	)

Return the total nitrogen of the specified branch.

TN = TKN + NOx_N

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

_branch_flow_helper()

def PooPyLab.unit_procs.streams.splitter._branch_flow_helper (   self )

private

Calculate 1 of the 3 branches' flow based on the other 2.

   1) Side outlet flow (_so_flow) can be set by
     1A) either WAS (_SRT_controller) or direct user input
     2A) upstream (non _SRT_controller)
   2) Main outlet flow (_mo_flow) can be set by
     2A) upstream automatically
     2B) direct user/run_time input
   3) Inlet flow is dependent on the two outlet branches' settings back
   tracing will be required to make sure flows are balanced if both main
   and side outlet flows are set either by user or run time SRT control.

See

set_flow_data_src(),

discharge().

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

Reimplemented in PooPyLab.unit_procs.streams.effluent, PooPyLab.unit_procs.streams.influent, and PooPyLab.unit_procs.streams.pipe.

_check_conc_cnvg()

def PooPyLab.unit_procs.streams.splitter._check_conc_cnvg (   self,   curr_comps = [],   prev_comps = [],   abs_lim = 1E-6  )

private

Check the convergence of model components (concentrations).

Parameters

curr_comps	current model components
prev_comps	prevous round model components
abs_lim	absolute limit for convergence

Retrun

list of bool for each model component's convergence status

See

is_converged()

Reimplemented from PooPyLab.unit_procs.base.poopy_lab_obj.

set_as_SRT_controller()

def PooPyLab.unit_procs.streams.splitter.set_as_SRT_controller	(		self,
			setting = False
	)

Set the current splitter as an Solids Retention Time controller.

   There are specific rules for connected an SRT controlling splitter.
   Once set, the splitter shall have a sidestream connected to a pipe
   followed by a WAS (waste activated sludge) unit.

   Once set True, the sidestream flow will be determined during simulation
   by the downstream WAS unit.

Parameters

setting

True/False

Return

None

See

utils.pfd.check();

utils.pfd._check_connection().

Reimplemented in PooPyLab.unit_procs.physchem.final_clarifier.

_sum_helper()

def PooPyLab.unit_procs.streams.splitter._sum_helper (   self,   branch = 'Main',   index_list = []  )

private

Sum up the model components indicated by the index_list.

Parameters

branch	{'Inlet'|'Main'|'Side'}
index_list	a list of indices for the model components to use

Return

float

---

The documentation for this class was generated from the following file:

• /home/kai/PythonPrograms/PooPyLab_Project/PooPyLab/unit_procs/streams.py