Numerical simulation of a hydrogen fuelled gas turbine combustor Paolo Gobbato*, Massimo Masi, Andrea Toffolo, Andrea Lazzaretto Department of Mechanical Engineering, University of Padova, Via Venezia 1, 35131 Padova, Italy article info Article history: Received 31 March 2010 Received in revised form 2 November 2010 Accepted 10 January 2011 Available online 15 February 2011 Keywords: Hydrogen fuelled gas turbine Combustor CFD analysis Liner temperatures Hydrogen turbine inlet temperature calculation abstract The interest for hydrogen-fuelled combustors is recently growing thanks to the develop- ment of gas turbines fed by high content hydrogen syngas. The diffusion flame combustion is a well-known and consolidated technology in the field of industrial gas turbine appli- cations. However, few CFD analyses on commercial medium size heavy duty gas turbine fuelled with pure hydrogen are available in the literature. This paper presents a CFD simulation of the air-hydrogen reacting flow inside a diffusion flame combustor of a single shaft gas turbine. The 3D geometrical model extends from the compressor discharge to the gas turbine inlet (both liner and air plenum are included). A coarse grid and a very simplified reaction scheme are adopted to evaluate the capability of a rather basic model to predict the temperature field inside the combustor. The interest is focused on the liner wall temperatures and the turbine inlet temperature profile since they could affect the reli- ability of components designed for natural gas operation. Data of a full-scale experimental test are employed to validate the numerical results. The calculated thermal field is useful to explain the non-uniform distribution of the temperature measured at the turbine inlet. Copyright ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. 1. Introduction In the last decade several research studies have been carried out on hydrogen combustion in gas turbines for stationary applications [1e5]. The main reasons for the growing interest in this topic are the increasing cost of fossil fuels and the atmospheric climate changes. The prices of oil and natural gas encourage heat and electric power generation from the combustion of industrial by-products, such as refinery and manufactured coal gases (e.g. coal oven gas), which are often characterised by a high hydrogen content by volume [5e7]. On the other hand, the increasing concern about global warming and climate change issues pushes towards clean and sustainable cycles (e.g. IGCC, Integrated Gasification Combined Cycle) in which hydrogen often plays an important role as energy carrier. In fact, hydrogen percentage in the gas stream obtained by gasification is typically from 25% to 40% by volume and sometimes exceeds 50% [1,6]. The natural gas lean-premixed combustors have to undergo some modifications if fed with hydrogen rich fuels, due to the combined effect of hydrogen shorter autoignition delay and faster flame speed. The influence of fuel composi- tion on blowout, flashback, autoignition and stability charac- teristics of premixed combustors are widely discussed in Ref. [8]. On the other hand, the addition of hydrogen to hydrocarbon fuels extends the stable combustion range to leaner mixtures, thanks to hydrogen wider flammability limits. This results in stable operation at lower temperatures in the combustion zone, and, therefore, in a lower production of thermal nitric oxides (NOx) [9,10]. * Corresponding author. Tel.: þ39 049 827 6748; fax: þ39 049 827 6785. E-mail address: paolo.gobbato@unipd.it (P. Gobbato). Available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy 36 (2011) 7993 e8002 0360-3199/$ e see front matter Copyright ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2011.01.045