def analyse(self, pamb, Tamb):
"""Run the exergy analysis.
Parameters
----------
pamb : float
Ambient pressure value for analysis, provide value in network's
pressure unit.
Tamb : float
Ambient temperature value for analysis, provide value in network's
temperature unit.
"""
pamb_SI = hlp.convert_to_SI('p', pamb, self.nw.p_unit)
Tamb_SI = hlp.convert_to_SI('T', Tamb, self.nw.T_unit)
# reset data
self.component_data = pd.DataFrame(
columns=['E_F', 'E_P', 'E_D', 'epsilon', 'group'], dtype='float64')
self.bus_data = self.component_data.copy()
self.connection_data = pd.DataFrame(
columns=['e_PH', 'e_T', 'e_M', 'E_PH', 'E_T', 'E_M'],
dtype='float64')
self.network_data = pd.Series(index=['E_F', 'E_P', 'E_D', 'E_L'],
dtype='float64')
self.network_data[:] = 0
# physical exergy of connections
for conn in self.nw.conns['object']:
conn.get_physical_exergy(pamb_SI, Tamb_SI)
self.connection_data.loc[conn.label] = [
conn.ex_physical, conn.ex_therm, conn.ex_mech,
conn.Ex_physical, conn.Ex_therm, conn.Ex_mech
]
self.sankey_data = {}
for label in self.reserved_fkt_groups:
self.sankey_data[label] = pd.DataFrame(columns=['value', 'cat'],
dtype='object')
# exergy balance of components
for cp in self.nw.comps['object']:
# save component information
cp.exergy_balance(Tamb_SI)
if not hasattr(cp, 'fkt_group'):
cp.fkt_group = cp.label
self.component_data.loc[cp.label] = [
cp.E_F, cp.E_P, cp.E_D, cp.epsilon, cp.fkt_group
]
if cp.fkt_group in self.reserved_fkt_groups:
msg = (
'The labels ' + ', '.join(self.reserved_fkt_groups) + ' '
'cannot be used by components (if no group was assigned) '
'or component groups in the exergy analysis. Found '
'component/group with name ' + cp.fkt_group + '.')
raise ValueError(msg)
elif cp.fkt_group not in self.sankey_data:
self.sankey_data[cp.fkt_group] = pd.DataFrame(
columns=['value', 'cat'], dtype='object')
self.evaluate_busses(cp)
self.network_data.loc['E_D'] = (self.component_data['E_D'].sum() +
self.bus_data['E_D'].sum())
self.network_data.loc['E_F'] = abs(self.network_data.loc['E_F'])
self.network_data.loc['E_P'] = abs(self.network_data.loc['E_P'])
self.network_data.loc['epsilon'] = (self.network_data.loc['E_P'] /
self.network_data.loc['E_F'])
# calculate exergy destruction ratios for components/busses
E_F = self.network_data.loc['E_F']
E_D = self.network_data.loc['E_D']
self.component_data['y_Dk'] = self.component_data['E_D'] / E_F
self.component_data['y*_Dk'] = self.component_data['E_D'] / E_D
self.bus_data['y_Dk'] = self.bus_data['E_D'] / E_F
self.bus_data['y*_Dk'] = self.bus_data['E_D'] / E_D
residual = abs(self.network_data.loc['E_F'] -
self.network_data.loc['E_P'] -
self.network_data.loc['E_D'] -
self.network_data.loc['E_L'])
if residual >= err**0.5:
msg = (
'The exergy balance of your network is not closed (residual '
'value is ' + str(round(residual, 6)) + ', but should be '
'smaller than ' + str(err**0.5) + '), you should check the '
'component and network exergy data and check, if network is '
'properly setup for the exergy analysis.')
logging.error(msg)
self.create_group_data()
def comp_init(self, nw):
Component.comp_init(self, nw, num_eq=len(nw.fluids) + 1)
self.Tamb.val_SI = convert_to_SI('T', self.Tamb.val, nw.T_unit)