Study on Reduced Chemical Mechanisms of Ammonia / Methane Combustion under Gas Turbine Conditions

On September 1st, academic journal Energy & Fuels published a new paper that features research coming out of the UK’s Cardiff University and Ireland’s University of Limerick.

This study demonstrates a “reduced mechanism” for simulating the “robust numerical analyses with detailed chemistry” necessary for the “industrial implementation” of ammonia in gas turbine combustion for “future power generation.”

Here’s the abstract:

As an alternative fuel and hydrogen carrier, ammonia is believed to have good potential for future power generation. To explore the feasibility of co-firing ammonia with methane, studies involving robust numerical analyses with detailed chemistry are required to progress toward industrial implementation. Therefore, the objective of this study is to determine a reduced mechanism for simulation studies of ammonia/methane combustion in practical gas turbine combustor conditions. First, five different-sized reduced mechanisms of the well-known Konnov’s mechanism were compared. The reduced mechanisms were tested for ignition delay time validation (zero dimensional) using ammonia/methane mixtures at high-pressure conditions relevant to gas turbine devices. Furthermore, the combustion products of ammonia/methane premixed laminar flames (one dimensional) were validated with the results from the full Konnov’s mechanism. Finally, computational fluid dynamics simulations of a turbulent flame (two dimensional) with all of the reduced mechanisms were performed under high-temperature and high-pressure conditions representative of industrial systems. Results show that several of the reduced mechanisms utilized performed reasonably well in combustion simulation studies under gas turbine conditions. Hence, a reaction mechanism with 48 species and 500 elementary reactions is recommended for future studies.

The paper is available online (registration required for full access).

The authors are:
Hua Xiao^†, Micheal Howard^‡, Agustin Valera-Medina^†, Stephen Dooley^‡, and Philip J. Bowen^†
† College of Physical Sciences and Engineering, Cardiff University, United Kingdom
^‡ Materials & Surface Institute, University of Limerick, Ireland