Model development for the simulation of the hydrogen addition effect onto the NOx emission of an industrial combustor

The impact on to NOx of three different natural gas compositions, including a hydrogen-enriched fuel blend, is numerically investigated with high-fidelity simulations in the heavy-duty gas turbine NOVA LT16® combustor at relevant engine conditions. For describing the NO formation, a novel emission model based on the characteristic NOx-Damköhler number is presented and used to process the LES solution at run time. The numerical predictions are contrasted to the measurements obtained in a dedicated campaign on a full-annular combustor rig, showing a limited discrepancy against the experimental data for any investigated Test Point. The sources contributing to the NO formation are analysed in detail, helping to shed some light on the mechanisms behind the NO formation in the combustor.