Add support for T(p,h) in a few gas FPs by adding it

as a Newton inversion of h(p,T) in HelmhotzFP refs idaholab#29620

modules/fluid_properties/include/fluidproperties/HelmholtzFluidProperties.h

@@ -55,6 +55,8 @@ class HelmholtzFluidProperties : public SinglePhaseFluidProperties
   virtual Real h_from_p_T(Real pressure, Real temperature) const override;
   virtual void h_from_p_T(Real p, Real T, Real & h, Real & dh_dp, Real & dh_dT) const override;
 
+  virtual Real T_from_p_h(Real pressure, Real enthalpy) const override;
+
   /**
    * Pressure as a function of density and temperature
    *

modules/fluid_properties/src/fluidproperties/HelmholtzFluidProperties.C

@@ -216,6 +216,24 @@ HelmholtzFluidProperties::h_from_p_T(
           molarMass();
 }
 
+Real
+HelmholtzFluidProperties::T_from_p_h(Real pressure, Real enthalpy) const
+{
+  auto lambda = [&](Real pressure, Real current_T, Real & new_h, Real & dh_dp, Real & dh_dT)
+  { h_from_p_T(pressure, current_T, new_h, dh_dp, dh_dT); };
+  Real T = FluidPropertiesUtils::NewtonSolve(
+               pressure, enthalpy, _T_initial_guess, _tolerance, lambda, name() + "::T_from_p_h")
+               .first;
+  // check for nans
+  if (std::isnan(T))
+    mooseError("Conversion from enthalpy (h = ",
+               enthalpy,
+               ") and pressure (p = ",
+               pressure,
+               ") to temperature failed to converge.");
+  return T;
+}
+
 Real
 HelmholtzFluidProperties::p_from_rho_T(Real density, Real temperature) const
 {