class TestHeatPump:
def setup(self):
# %% network setup
self.nw = Network(fluids=['water', 'NH3'],
T_unit='C',
p_unit='bar',
h_unit='kJ / kg',
m_unit='kg / s')
# %% components
# sources & sinks
cc_coolant = CycleCloser('coolant cycle closer')
cc_consumer = CycleCloser('consumer cycle closer')
amb_in = Source('source ambient')
amb_out = Sink('sink ambient')
ic_in = Source('source intercool')
ic_out = Sink('sink intercool')
# consumer system
cd = HeatExchanger('condenser')
rp = Pump('recirculation pump')
cons = HeatExchangerSimple('consumer')
# evaporator system
va = Valve('valve')
dr = Drum('drum')
ev = HeatExchanger('evaporator')
su = HeatExchanger('superheater')
pu = Pump('pump evaporator')
# compressor-system
cp1 = Compressor('compressor 1')
cp2 = Compressor('compressor 2')
he = HeatExchanger('intercooler')
# busses
self.power = Bus('total compressor power')
self.power.add_comps({
'comp': cp1,
'base': 'bus'
}, {
'comp': cp2,
'base': 'bus'
})
self.heat = Bus('total delivered heat')
self.heat.add_comps({'comp': cd, 'char': -1})
self.nw.add_busses(self.power, self.heat)
# %% connections
# consumer system
c_in_cd = Connection(cc_coolant, 'out1', cd, 'in1')
cb_rp = Connection(cc_consumer, 'out1', rp, 'in1')
rp_cd = Connection(rp, 'out1', cd, 'in2')
self.cd_cons = Connection(cd, 'out2', cons, 'in1')
cons_cf = Connection(cons, 'out1', cc_consumer, 'in1')
self.nw.add_conns(c_in_cd, cb_rp, rp_cd, self.cd_cons, cons_cf)
# connection condenser - evaporator system
cd_va = Connection(cd, 'out1', va, 'in1')
self.nw.add_conns(cd_va)
# evaporator system
va_dr = Connection(va, 'out1', dr, 'in1')
dr_pu = Connection(dr, 'out1', pu, 'in1')
pu_ev = Connection(pu, 'out1', ev, 'in2')
ev_dr = Connection(ev, 'out2', dr, 'in2')
dr_su = Connection(dr, 'out2', su, 'in2')
self.nw.add_conns(va_dr, dr_pu, pu_ev, ev_dr, dr_su)
self.amb_in_su = Connection(amb_in, 'out1', su, 'in1')
su_ev = Connection(su, 'out1', ev, 'in1')
ev_amb_out = Connection(ev, 'out1', amb_out, 'in1')
self.nw.add_conns(self.amb_in_su, su_ev, ev_amb_out)
# connection evaporator system - compressor system
su_cp1 = Connection(su, 'out2', cp1, 'in1')
self.nw.add_conns(su_cp1)
# compressor-system
cp1_he = Connection(cp1, 'out1', he, 'in1')
he_cp2 = Connection(he, 'out1', cp2, 'in1')
cp2_c_out = Connection(cp2, 'out1', cc_coolant, 'in1')
ic_in_he = Connection(ic_in, 'out1', he, 'in2')
he_ic_out = Connection(he, 'out2', ic_out, 'in1')
self.nw.add_conns(cp1_he, he_cp2, ic_in_he, he_ic_out, cp2_c_out)
# %% component parametrization
# condenser system
x = np.array([
0, 0.0625, 0.125, 0.1875, 0.25, 0.3125, 0.375, 0.4375, 0.5, 0.5625,
0.6375, 0.7125, 0.7875, 0.9, 0.9875, 1, 1.0625, 1.125, 1.175,
1.2125, 1.2375, 1.25
])
y = np.array([
0.0076, 0.1390, 0.2731, 0.4003, 0.5185, 0.6263, 0.7224, 0.8056,
0.8754, 0.9312, 0.9729, 1.0006, 1.0203, 1.0158, 1.0051, 1.0000,
0.9746, 0.9289, 0.8832, 0.8376, 0.7843, 0.7614
])
rp.set_attr(eta_s=0.8,
design=['eta_s'],
offdesign=['eta_s_char'],
eta_s_char={
'char_func': CharLine(x, y),
'param': 'm'
})
cons.set_attr(pr=1, design=['pr'], offdesign=['zeta'])
# evaporator system
x = np.linspace(0, 2.5, 26)
y = np.array([
0.000, 0.164, 0.283, 0.389, 0.488, 0.581, 0.670, 0.756, 0.840,
0.921, 1.000, 1.078, 1.154, 1.228, 1.302, 1.374, 1.446, 1.516,
1.585, 1.654, 1.722, 1.789, 1.855, 1.921, 1.986, 2.051
])
kA_char1 = {'char_func': CharLine(x, y), 'param': 'm'}
x = np.array([
0.0100, 0.0400, 0.0700, 0.1100, 0.1500, 0.2000, 0.2500, 0.3000,
0.3500, 0.4000, 0.4500, 0.5000, 0.5500, 0.6000, 0.6500, 0.7000,
0.7500, 0.8000, 0.8500, 0.9000, 0.9500, 1.0000, 1.5000, 2.0000
])
y = np.array([
0.0185, 0.0751, 0.1336, 0.2147, 0.2997, 0.4118, 0.5310, 0.6582,
0.7942, 0.9400, 0.9883, 0.9913, 0.9936, 0.9953, 0.9966, 0.9975,
0.9983, 0.9988, 0.9992, 0.9996, 0.9998, 1.0000, 1.0008, 1.0014
])
kA_char2 = {'char_func': CharLine(x, y), 'param': 'm'}
ev.set_attr(pr1=1,
pr2=.999,
ttd_l=5,
design=['ttd_l'],
offdesign=['kA_char'],
kA_char1=kA_char1,
kA_char2=kA_char2)
# no kA modification for hot side!
x = np.array([0, 1])
y = np.array([1, 1])
kA_char1 = {'char_func': CharLine(x, y), 'param': 'm'}
# characteristic line for superheater kA
x = np.array(
[0, 0.045, 0.136, 0.244, 0.43, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2])
y = np.array(
[0, 0.037, 0.112, 0.207, 0.5, 0.8, 0.85, 0.9, 0.95, 1, 1.04, 1.07])
kA_char2 = {'char_func': CharLine(x, y), 'param': 'm'}
su.set_attr(kA_char1=kA_char1,
kA_char2=kA_char2,
offdesign=['zeta1', 'zeta2', 'kA_char'])
x = np.array([
0, 0.0625, 0.125, 0.1875, 0.25, 0.3125, 0.375, 0.4375, 0.5, 0.5625,
0.6375, 0.7125, 0.7875, 0.9, 0.9875, 1, 1.0625, 1.125, 1.175,
1.2125, 1.2375, 1.25
])
y = np.array([
0.0076, 0.1390, 0.2731, 0.4003, 0.5185, 0.6263, 0.7224, 0.8056,
0.8754, 0.9312, 0.9729, 1.0006, 1.0203, 1.0158, 1.0051, 1.0000,
0.9746, 0.9289, 0.8832, 0.8376, 0.7843, 0.7614
])
pu.set_attr(eta_s=0.8,
design=['eta_s'],
offdesign=['eta_s_char'],
eta_s_char={
'char_func': CharLine(x, y),
'param': 'm'
})
# compressor system
x = np.array([0, 0.4, 1, 1.2])
y = np.array([0.5, 0.9, 1, 1.1])
cp1.set_attr(eta_s=0.8,
design=['eta_s'],
offdesign=['eta_s_char'],
eta_s_char={
'char_func': CharLine(x, y),
'param': 'm'
})
cp2.set_attr(eta_s=0.8,
design=['eta_s'],
offdesign=['eta_s_char'],
eta_s_char={
'char_func': CharLine(x, y),
'param': 'm'
})
# characteristic line for intercooler kA
x = np.linspace(0, 2.5, 26)
y = np.array([
0.0000, 0.2455, 0.3747, 0.4798, 0.5718, 0.6552, 0.7323, 0.8045,
0.8727, 0.9378, 1.0000, 1.0599, 1.1176, 1.1736, 1.2278, 1.2806,
1.3320, 1.3822, 1.4313, 1.4792, 1.5263, 1.5724, 1.6176, 1.6621,
1.7058, 1.7488
])
kA_char1 = {'char_func': CharLine(x, y), 'param': 'm'}
x = np.linspace(0, 2.5, 26)
y = np.array([
0.000, 0.164, 0.283, 0.389, 0.488, 0.581, 0.670, 0.756, 0.840,
0.921, 1.000, 1.078, 1.154, 1.228, 1.302, 1.374, 1.446, 1.516,
1.585, 1.654, 1.722, 1.789, 1.855, 1.921, 1.986, 2.051
])
kA_char2 = {'char_func': CharLine(x, y), 'param': 'm'}
he.set_attr(kA_char1=kA_char1,
kA_char2=kA_char2,
offdesign=['zeta1', 'zeta2', 'kA_char'])
# characteristic line for condenser kA
x = np.linspace(0, 2.5, 26)
y = np.array([
0.0000, 0.2455, 0.3747, 0.4798, 0.5718, 0.6552, 0.7323, 0.8045,
0.8727, 0.9378, 1.0000, 1.0599, 1.1176, 1.1736, 1.2278, 1.2806,
1.3320, 1.3822, 1.4313, 1.4792, 1.5263, 1.5724, 1.6176, 1.6621,
1.7058, 1.7488
])
kA_char1 = {'char_func': CharLine(x, y), 'param': 'm'}
x = np.linspace(0, 2.5, 26)
y = np.array([
0.000, 0.164, 0.283, 0.389, 0.488, 0.581, 0.670, 0.756, 0.840,
0.921, 1.000, 1.078, 1.154, 1.228, 1.302, 1.374, 1.446, 1.516,
1.585, 1.654, 1.722, 1.789, 1.855, 1.921, 1.986, 2.051
])
kA_char2 = {'char_func': CharLine(x, y), 'param': 'm'}
cd.set_attr(kA_char1=kA_char1,
kA_char2=kA_char2,
pr2=0.9998,
design=['pr2'],
offdesign=['zeta2', 'kA_char'])
# %% connection parametrization
# condenser system
c_in_cd.set_attr(fluid={'water': 0, 'NH3': 1}, p=60)
rp_cd.set_attr(T=60, fluid={'water': 1, 'NH3': 0}, p=10)
self.cd_cons.set_attr(T=105)
cd_va.set_attr(p=Ref(c_in_cd, 1, -0.01), Td_bp=-5, design=['Td_bp'])
# evaporator system cold side
pu_ev.set_attr(m=Ref(va_dr, 10, 0), p0=5)
dr_su.set_attr(p0=5, T=5)
su_cp1.set_attr(p=Ref(dr_su, 1, -0.05), Td_bp=5, design=['Td_bp', 'p'])
# evaporator system hot side
self.amb_in_su.set_attr(m=20, T=12, p=1, fluid={'water': 1, 'NH3': 0})
su_ev.set_attr(p=Ref(self.amb_in_su, 1, -0.001), design=['p'])
ev_amb_out.set_attr()
# compressor-system
cp1_he.set_attr(p=15)
he_cp2.set_attr(T=40, p=Ref(cp1_he, 1, -0.01), design=['T', 'p'])
ic_in_he.set_attr(p=1, T=20, m=5, fluid={'water': 1, 'NH3': 0})
he_ic_out.set_attr(p=Ref(ic_in_he, 1, -0.002), design=['p'])
def test_model(self):
"""
Test the operating points of the heat pump against a different model.
By now, not all characteristic functions of the original model are
available in detail, thus perfect matching is not possible!
"""
self.nw.solve('design')
self.nw.save('tmp')
self.nw.print_results()
# input values from ebsilon
T = [105, 100, 90, 80]
m_source = np.array([[23, 22, 20, 18, 16], [27, 24, 20, 16, 12],
[31, 25, 20, 15, 10], [33, 26, 20, 15, 10]])
COP = np.array([[2.436, 2.414, 2.368, 2.338, 2.287],
[2.591, 2.523, 2.448, 2.355, 2.216],
[2.777, 2.635, 2.557, 2.442, 2.243],
[2.866, 2.711, 2.629, 2.528, 2.351]])
i = 0
for T in T:
j = 0
self.cd_cons.set_attr(T=T)
for m in m_source[i]:
self.amb_in_su.set_attr(m=m)
if j == 0:
self.nw.solve('offdesign',
design_path='tmp',
init_path='tmp')
else:
self.nw.solve('offdesign', design_path='tmp')
# relative deviation should not exceed 6.5 %
# this should be much less, unfortunately not all ebsilon
# characteristics are available, thus it is
# difficult/impossible to match the models perfectly!
d_rel_COP = abs(self.heat.P.val / self.power.P.val -
COP[i, j]) / COP[i, j]
msg = ('The deviation in COP should be less than 0.065, is ' +
str(d_rel_COP) + ' at mass flow ' + str(m) +
' and temperature ' + str(T) + '.')
assert d_rel_COP < 0.065, msg
j += 1
i += 1
shutil.rmtree('./tmp', ignore_errors=True)
dh_c.set_attr(T=60,
p=5,
fluid={
'CO2': 0,
'Ar': 0,
'N2': 0,
'O2': 0,
'H2O': 1,
'CH4': 0
})
dh_w.set_attr(T=90)
# %%
nw.solve(mode='design')
nw.print_results()
nw.save('design_point')
document_model(nw, filename='report_design.tex')
power.set_attr(P=-100e6)
nw.solve(mode='offdesign',
init_path='design_point',
design_path='design_point')
nw.print_results()
document_model(nw, filename='report_offdesign.tex')
power.set_attr(P=1 / 0.9 * 0.8 * power.P.val)
nw.solve(mode='offdesign', design_path='design_point')
nw.print_results()
class TestPiping:
def setup_piping_network(self, instance):
self.nw = Network(['CH4'], T_unit='C', p_unit='bar')
self.source = Source('source')
self.sink = Sink('sink')
self.c1 = Connection(self.source, 'out1', instance, 'in1')
self.c2 = Connection(instance, 'out1', self.sink, 'in1')
self.nw.add_conns(self.c1, self.c2)
def test_Valve(self):
"""Test component properties of valves."""
instance = Valve('valve')
self.setup_piping_network(instance)
# parameter specification
self.c1.set_attr(fluid={'CH4': 1}, m=10, p=10, T=120)
self.c2.set_attr(p=1)
# test variable pressure ration
instance.set_attr(pr='var')
self.nw.solve('design')
convergence_check(self.nw.lin_dep)
pr = round(self.c2.p.val_SI / self.c1.p.val_SI, 2)
msg = ('Value of pressure ratio must be ' + str(pr) + ', is ' +
str(round(instance.pr.val, 2)) + '.')
assert pr == round(instance.pr.val, 2), msg
# test variable zeta value
zeta = round(instance.zeta.val, 0)
instance.set_attr(zeta='var', pr=None)
self.nw.solve('design')
convergence_check(self.nw.lin_dep)
msg = ('Value of dimension independent zeta value must be ' +
str(zeta) + ', is ' + str(round(instance.zeta.val, 0)) + '.')
assert zeta == round(instance.zeta.val, 0), msg
# dp char
x = np.array([8, 9, 10, 11, 12])
y = np.array([5, 8, 9, 9.5, 9.6]) * 1e5
dp_char = CharLine(x, y)
instance.set_attr(zeta=None,
dp_char={
'char_func': dp_char,
'is_set': True
})
m = 11
self.c1.set_attr(m=m)
self.c2.set_attr(p=np.nan)
self.nw.solve('design')
convergence_check(self.nw.lin_dep)
self.nw.print_results()
dp = round(-dp_char.evaluate(m), 0)
dp_act = round(self.c2.p.val_SI - self.c1.p.val_SI)
msg = ('The pressure drop at the valve should be ' + str(dp) + ' but '
'is ' + str(dp_act) + '.')
assert dp == dp_act, msg
def test_Pipe(self):
"""Test component properties of pipe."""
instance = Pipe('pipe')
self.setup_piping_network(instance)
