def test_cv():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("prop.txt", col=7)
phase = read_data("prop.txt", col=13)
for i, c in enumerate(cond):
if c[2] == "undefined":
continue
if (c[0] > 640 and c[0] < 680) and (c[1] > 2.1e7 and c[1] < 3.1e7):
#near critical and non-analytic terms were omitted
continue
if phase[i][2] in ["liquid", "supercritical"]:
p = "Liq"
else:
p = "Vap"
model.prop_in.temperature.set_value(c[0])
model.prop_in.pressure = c[1]
cv = value(model.prop_in.cv_mol_phase[p] / model.prop_in.mw / 1000)
rho = value(model.prop_in.dens_mass_phase[p])
if rho > 250 and rho < 420 and c[0] < 700 and c[0] > 640:
tol = 0.03 # steep part in sc region
else:
tol = 0.003
assert (abs(cv - c[2]) / c[2] < tol)
def test_tau_sat():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("sat_prop.txt", col=2)
for c in cond:
tau = value(model.prop_in.func_tau_sat(c[1] / 1000.0))
T = 647.096 / tau
print("{}, {}, {}".format(c[1], c[0], T))
assert (abs(T - c[0]) < 0.1)
def test_liquid_enthalpy_sat():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("sat_prop.txt", col=5)
for c in cond:
if c[0] > 645: # getting very close to ciritical point
tol = 0.01
else:
tol = 0.001
model.prop_in.pressure = c[1]
enth = value(model.prop_in.enth_mol_sat_phase["Liq"] /
model.prop_in.mw / 1000.0)
assert (abs((enth - c[2]) / c[2]) < tol)
def test_vapor_density_sat():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("sat_prop.txt", col=14)
for c in cond:
if c[0] > 645: # getting very close to ciritical point
tol = 0.01
else:
tol = 0.001
model.prop_in.temperature.set_value(c[0])
model.prop_in.pressure = c[1]
rho = value(model.prop_in.dens_mass_phase["Vap"])
assert (abs(rho - c[2]) / c[2] < tol)
def test_enthalpy_vapor_as_function_of_p_and_tau():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("prop.txt", col=5)
phase = read_data("prop.txt", col=13)
for i, c in enumerate(cond):
if phase[i][2] in ["liquid", "supercritical"]:
continue
model.prop_in.temperature.set_value(c[0])
h = value(model.prop_in.func_hvpt(c[1] / 1000, 647.096 / c[0]))
rho = value(model.prop_in.dens_mass_phase["Vap"])
if rho > 250 and rho < 420 and c[0] < 700 and c[0] > 640:
tol = 0.03 # steep part in sc region
else:
tol = 0.003
assert (abs(h - c[2]) / c[2] < tol)
def test_entropy():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("prop.txt", col=6)
phase = read_data("prop.txt", col=13)
for i, c in enumerate(cond):
if phase[i][2] in ["liquid", "supercritical"]:
p = "Liq"
else:
p = "Vap"
model.prop_in.temperature.set_value(c[0])
model.prop_in.pressure = c[1]
s = value(model.prop_in.entr_mol_phase[p] / model.prop_in.mw / 1000)
rho = value(model.prop_in.dens_mass_phase[p])
if rho > 250 and rho < 420 and c[0] < 700 and c[0] > 640:
tol = 0.03 # steep part in sc region
else:
tol = 0.003
assert (abs(s - c[2]) / c[2] < tol)
def test_density():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond = read_data("prop.txt", col=2)
phase = read_data("prop.txt", col=13)
for i, c in enumerate(cond):
if phase[i][2] in ["liquid", "supercritical"]:
p = "Liq"
else:
p = "Vap"
model.prop_in.temperature.set_value(c[0])
model.prop_in.pressure = c[1]
rho = value(model.prop_in.dens_mass_phase[p])
if rho > 250 and rho < 420 and c[0] < 700 and c[0] > 645:
tol = 0.03 # steep part in sc region
elif c[1] < 20:
tol = 0.005 #very low pressure < 20 Pa
else:
tol = 0.001
assert (abs(rho - c[2]) / c[2] < tol)
def test_enthalpy_of_vaporization():
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(
default={"parameters": model.prop_param})
cond_liq = read_data("sat_prop.txt", col=5)
cond_vap = read_data("sat_prop.txt", col=17)
for i, c in enumerate(cond_liq):
if c[0] > 645: # getting very close to ciritical point
tol = 0.05
else:
tol = 0.001
model.prop_in.pressure.value = c[1]
enth = value(model.prop_in.dh_vap_mol / model.prop_in.mw / 1000.0)
enth_dat = cond_vap[i][2] - c[2]
if abs(enth_dat) > 1e-8:
assert (abs((enth - enth_dat) / enth_dat) < tol)
else:
assert (abs(enth - enth_dat) < tol)
#Over Critical Pressure
model.prop_in.pressure = model.prop_in.config.parameters.pressure_crit * 1.1
enth = value(model.prop_in.dh_vap_mol / model.prop_in.mw / 1000.0)
assert (abs(enth) < 0.001)
def make_model(self):
model = ConcreteModel()
model.prop_param = iapws95.Iapws95ParameterBlock()
model.prop_in = iapws95.Iapws95StateBlock(default={"parameters":model.prop_param})
return model