def test_set_Tx(self):
"""Set a pair of properties of the State and check the properties.
Also works as a functional/regression test of CoolProp.
"""
s = State(substance="water")
s.Tx = Q_(400.0, "K"), Q_(0.5, "dimensionless")
assert isclose_quant(s.T, Q_(400.0, "K"))
assert isclose_quant(s.p, Q_(245769.34557103913, "Pa"))
assert isclose_quant(s.Tx[0], Q_(400.0, "K"))
assert isclose_quant(s.Tx[1], Q_(0.5, "dimensionless"))
assert isclose_quant(s.u, Q_(1534461.5163075812, "J/kg"))
assert isclose_quant(s.s, Q_(4329.703956664546, "J/(kg*K)"))
assert isclose_quant(s.cp, Q_(4056.471547685226, "J/(kg*K)"))
assert isclose_quant(s.cv, Q_(2913.7307270395363, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(0.3656547423394701, "m**3/kg"))
assert isclose_quant(s.h, Q_(1624328.2430353598, "J/kg"))
assert isclose_quant(s.x, Q_(0.5, "dimensionless"))
s.Tx = Q_(400.0, "K"), Q_(50, "percent")
assert isclose_quant(s.T, Q_(400.0, "K"))
assert isclose_quant(s.p, Q_(245769.34557103913, "Pa"))
assert isclose_quant(s.Tx[0], Q_(400.0, "K"))
assert isclose_quant(s.Tx[1], Q_(0.5, "dimensionless"))
assert isclose_quant(s.u, Q_(1534461.5163075812, "J/kg"))
assert isclose_quant(s.s, Q_(4329.703956664546, "J/(kg*K)"))
assert isclose_quant(s.cp, Q_(4056.471547685226, "J/(kg*K)"))
assert isclose_quant(s.cv, Q_(2913.7307270395363, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(0.3656547423394701, "m**3/kg"))
assert isclose_quant(s.h, Q_(1624328.2430353598, "J/kg"))
assert isclose_quant(s.x, Q_(0.5, "dimensionless"))
def test_set_hp(self):
"""Set a pair of properties of the State and check the properties.
Also works as a functional/regression test of CoolProp.
"""
s = State(substance="water")
s.hp = Q_(1061602.391543017, "J/kg"), Q_(101325.0, "Pa")
assert isclose_quant(s.T, Q_(373.1242958476843, "K"))
assert isclose_quant(s.p, Q_(101325.0, "Pa"))
assert isclose_quant(s.hp[0], Q_(1061602.391543017, "J/kg"))
assert isclose_quant(s.hp[1], Q_(101325.0, "Pa"))
assert isclose_quant(s.u, Q_(1013250, "J/kg"))
assert isclose_quant(s.s, Q_(3028.9867985920914, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(0.4772010021515822, "m**3/kg"))
assert isclose_quant(s.h, Q_(1061602.391543017, "J/kg"))
assert isclose_quant(s.x, Q_(0.28475636946248034, "dimensionless"))
s.hp = Q_(3336406.139862406, "J/kg"), Q_(101325.0, "Pa")
assert isclose_quant(s.T, Q_(700.9882316847855, "K"))
assert isclose_quant(s.p, Q_(101325.0, "Pa"))
assert isclose_quant(s.hp[0], Q_(3336406.139862406, "J/kg"))
assert isclose_quant(s.hp[1], Q_(101325.0, "Pa"))
assert isclose_quant(s.u, Q_(3013250, "J/kg"))
assert isclose_quant(s.s, Q_(8623.283568815832, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(3.189303132125469, "m**3/kg"))
assert isclose_quant(s.h, Q_(3336406.139862406, "J/kg"))
assert s.x is None
def test_eq(self):
"""Test equality comparison of states.
States are equal when their properties are equal and the substances are the
same.
"""
st_1 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
st_2 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
assert st_1 == st_2
def test_comparison(self):
"""Greater/less than comparisons are not supported."""
st_1 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
st_2 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
with pytest.raises(TypeError):
st_1 < st_2
with pytest.raises(TypeError):
st_1 <= st_2
with pytest.raises(TypeError):
st_1 > st_2
with pytest.raises(TypeError):
st_1 >= st_2
def test_set_properties_too_many_props_and_values(self):
"""Passing too many properties to _set_properties raises a StateError."""
s = State(substance="water")
with pytest.raises(StateError):
s._set_properties(
["T", "v", "h"],
[
Q_(373.1242958476844, "K"),
Q_(1.801983936953226, "m**3/kg"),
Q_(2730301.3859201893, "J/kg"),
],
)
def test_lowercase_input(self):
"""Substances should be able to be specified with lowercase letters."""
State(substance="water")
State(substance="r22")
State(substance="r134a")
State(substance="ammonia")
State(substance="propane")
State(substance="air")
State(substance="isobutane")
State(substance="carbondioxide")
State(substance="oxygen")
State(substance="nitrogen")
def test_set_hv(self):
"""Set a pair of properties of the State and check the properties.
Also works as a functional/regression test of CoolProp.
"""
s = State(substance="water")
s.hv = Q_(1061602.391543017, "J/kg"), Q_(0.4772010021515822, "m**3/kg")
assert isclose_quant(s.T, Q_(373.1242958476843, "K"))
assert isclose_quant(s.p, Q_(101325.0, "Pa"))
assert isclose_quant(s.hv[0], Q_(1061602.391543017, "J/kg"))
assert isclose_quant(s.hv[1], Q_(0.4772010021515822, "m**3/kg"))
assert isclose_quant(s.u, Q_(1013250, "J/kg"))
assert isclose_quant(s.s, Q_(3028.9867985920914, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(0.4772010021515822, "m**3/kg"))
assert isclose_quant(s.h, Q_(1061602.391543017, "J/kg"))
assert isclose_quant(s.x, Q_(0.28475636946248034, "dimensionless"))
def test_set_Tv(self):
"""Set a pair of properties of the State and check the properties.
Also works as a functional/regression test of CoolProp.
"""
s = State(substance="water")
s.Tv = Q_(400.0, "K"), Q_(1.801983936953226, "m**3/kg")
assert isclose_quant(s.T, Q_(400.0, "K"))
assert isclose_quant(s.p, Q_(101325.0, "Pa"))
assert isclose_quant(s.Tv[0], Q_(400.0, "K"))
assert isclose_quant(s.Tv[1], Q_(1.801983936953226, "m**3/kg"))
assert isclose_quant(s.u, Q_(2547715.3635084038, "J/kg"))
assert isclose_quant(s.s, Q_(7496.2021523754065, "J/(kg*K)"))
assert isclose_quant(s.cp, Q_(2009.2902478486988, "J/(kg*K)"))
assert isclose_quant(s.cv, Q_(1509.1482452129906, "J/(kg*K)"))
assert isclose_quant(s.v, Q_(1.801983936953226, "m**3/kg"))
assert isclose_quant(s.h, Q_(2730301.3859201893, "J/kg"))
assert s.x is None
def test_bad_dimensions(self, prop):
"""Setting bad dimensions for the input property raises a StateError."""
kwargs = {prop: Q_(1.0, "dimensionless")}
if prop == "v":
kwargs["T"] = Q_(300.0, "K")
else:
kwargs["v"] = Q_(1.0, "m**3/kg")
with pytest.raises(StateError):
State(substance="water", **kwargs)
def test_too_many_props(self):
"""Specifying too many properties should raise a ValueError."""
with pytest.raises(ValueError):
State(
substance="water",
T=Q_(300, "K"),
p=Q_(101325, "Pa"),
u=Q_(100, "kJ/kg"),
)
def test_bad_x_dimensions(self):
"""Setting bad dimensions for quality raises a StateError.
Must be done in a separate test because the "dimensionless"
sentinel value used in the other test is actually the correct
dimension for quality.
"""
with pytest.raises(StateError):
State(substance="water", T=Q_(300.0, "K"), x=Q_(1.01325, "K"))
def test_too_few_props(self):
"""Specifying too few properties should raise a value error."""
with pytest.raises(ValueError):
State(substance="water", T=Q_(300, "K"))
def test_quality_gt_one(self):
"""Vapor qualities greater than 1.0 should raise a StateError."""
with pytest.raises(StateError):
State(substance="water", x=Q_(2.0, "dimensionless"), p=Q_(101325, "Pa"))
def test_bad_substance(self):
"""A substance not in the approved list should raise a ValueError."""
with pytest.raises(ValueError):
State(substance="bad substance")
def test_TP_twophase(self):
"""Setting a two-phase mixture with T and p should raise a StateError."""
with pytest.raises(StateError):
State(substance="water", T=Q_(373.1242958476844, "K"), p=Q_(101325.0, "Pa"))
def test_unit_definitions(self):
"""All of the properties should have units defined."""
st = State("water")
props = st._all_props[:]
props.extend(st._read_only_props)
assert all([a in st._SI_units.keys() for a in props])
def test_negative_pressure(self):
"""Negative absolute pressures should raise a StateError."""
with pytest.raises(StateError):
State(substance="water", T=Q_(300, "K"), p=Q_(-101325, "Pa"))
def test_quality_lt_zero(self):
"""Vapor qualities less than 0.0 should raise a StateError."""
with pytest.raises(StateError):
State(substance="water", x=Q_(-1.0, "dimensionless"), p=Q_(101325, "Pa"))
def test_not_eq_sub(self):
"""States are not equal when substances are not the same."""
st_1 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
st_2 = State(substance="ammonia", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
assert not st_1 == st_2
def test_not_eq(self):
"""States are not equal when properties are not equal."""
st_1 = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
st_2 = State(substance="water", T=Q_(300.0, "K"), p=Q_(101325.0, "Pa"))
assert not st_1 == st_2
def test_bad_property_setting(self):
"""Regression test that pressure is lowercase p, not uppercase."""
s = State(substance="water")
with pytest.raises(AttributeError):
# Should be lowercase p
s.TP = Q_(400.0, "K"), Q_(101325.0, "Pa")
def test_bad_get_property(self):
"""Accessing attributes that aren't one of the properties or pairs raises."""
s = State(substance="water", T=Q_(400.0, "K"), p=Q_(101325.0, "Pa"))
with pytest.raises(AttributeError):
s.bad_get
def test_negative_volume(self):
"""Negative absolute specific volumes should raise a StateError."""
with pytest.raises(StateError):
State(substance="water", T=Q_(300, "K"), v=Q_(-10.13, "m**3/kg"))
def test_invalid_input_prop(self):
"""Invalid input properties should raise a ValueError."""
with pytest.raises(ValueError):
State(
substance="water", x=Q_(0.5, "dimensionless"), bad_prop=Q_(101325, "Pa")
)