Reply To: Energy source term related with chemical reaction in UDF

[Rob]

Any reason for not using the species reactions within a phase, or the chemistry options in the Phase panel in Fluent? You also want to update to 2023R2 (soon to be superceded by 2024R1) for new feature that will help with what you're doing. 

If materials are changing phase, you would usually include two materials, with one being solid/liquid and the second liquid/gas respectively. Formation enthalpy then includes the chemical and "phase" part (eg latent heat).