[Thermo] Use min/max temperatures from equation of state

The values in the liquidvapor.cti should be ignored, since this thermo data is
not actually applicable -- it is just used to set the reference state.

include/cantera/thermo/PureFluidPhase.h

@@ -43,6 +43,9 @@ public:
         m_tpx_name = name;
     }
 
+    virtual double minTemp(size_t k=npos) const;
+    virtual double maxTemp(size_t k=npos) const;
+
     virtual doublereal enthalpy_mole() const;
     virtual doublereal intEnergy_mole() const;
     virtual doublereal entropy_mole() const;

interfaces/cython/cantera/test/test_purefluid.py

@@ -17,6 +17,11 @@ class TestPureFluid(utilities.CanteraTest):
         self.assertNear(self.water.critical_temperature, 647.286)
         self.assertNear(self.water.critical_density, 317.0)
 
+    def test_temperature_limits(self):
+        co2 = ct.CarbonDioxide()
+        self.assertNear(co2.min_temp, 216.54)
+        self.assertNear(co2.max_temp, 1500.0)
+
     def test_set_state(self):
         self.water.PX = 101325, 0.5
         self.assertNear(self.water.P, 101325)

src/thermo/PureFluidPhase.cpp

@@ -73,6 +73,16 @@ void PureFluidPhase::setParametersFromXML(const XML_Node& eosdata)
     }
 }
 
+double PureFluidPhase::minTemp(size_t k) const
+{
+    return m_sub->Tmin();
+}
+
+double PureFluidPhase::maxTemp(size_t k) const
+{
+    return m_sub->Tmax();
+}
+
 doublereal PureFluidPhase::enthalpy_mole() const
 {
     setTPXState();