Cofiring of biogas in existing gas turbines is a feasible option to reduce the consumption of natural gas. However, admixing of biogas will have an effect on the combustion process. As a consequence, the burning velocity and, therefore, the flame stability may be affected when a significant amount of biogas is mixed with the natural gas. The effect of admixing natural gas with biogas on the stability of the combustion process in lean premixed gas turbines is insufficiently known. In the present paper, a Computational Fluid Dynamics (CFD) methodology will be presented for the assessment of the safe limit of biogas cofiring in a gasturbine. An advanced Flamelet/Flamefront combustion model [1, 2, 3] and the Coherent Flame Model [4] are utilized. In both models, the detailed GRI 3.0 reaction mechanism [5] has been used to describe the combustion chemistry. The degree of mixing of fuel and air in the lean premix-burners of the gasturbine has been determined with a separate CFD model of the burners.

This content is only available via PDF.
You do not currently have access to this content.