FLOX^® Combustion at High Power Density and High Flame Temperatures

In this contribution, an overview of the progress in the design of an enhanced FLOX^® burner is given. A fuel flexible burner concept was developed to fulfill the requirements of modern gas turbines: high specific power density, high turbine inlet temperature, and low NO_x emissions. The basis for the research work is numerical simulation. With the focus on pollutant emissions a detailed chemical kinetic mechanism is used in the calculations. A novel mixing control concept, called HiPerMix^®, and its application in the FLOX^® burner is presented. In view of the desired operational conditions in a gas turbine combustor this enhanced FLOX^® burner was manufactured and experimentally investigated at the DLR test facility. In the present work experimental and computational results are presented for natural gas and natural gas + hydrogen combustion at gas turbine relevant conditions and high adiabatic flame temperatures (up to T_ad = 2000 K). The respective power densities are P_A = 13.3 MW/m²/bar (NG) and P_A = 14.8 MW/m²/bar (NG + H₂) satisfying the demands of a gas turbine combustor. It is demonstrated that the combustion is complete and stable and that the pollutant emissions are very low.