A model for combustor dynamics for inclusion in a dynamic gas turbine engine simulation code

To improve upon the current capabilities of post-stall gas turbine combustor dynamic modeling and further the understanding of compressor-combustor interactions, a dynamic combustor model is developed for inclusion into a full engine simulation code. A flux-difference splitting algorithm is used to numerically integrate the quasi-one-dimensional Euler equations, supplemented with species mass conservation equations. The combustion model involves a single-step, global finite-rate chemistry scheme with a temperature-dependent activation energy. Source terms are used to account for mass bleed and mass injection, with additional capabilities to handle momentum and energy sources and sinks. The model is tested in a lean premixed dump combustor with comparisons to previous multidimensional numerical and experimental results. Preliminary numerical results for cold flow in a can-type gas turbine combustor are also presented. Experimental data from this combustor are also obtained in this study and include measurements of mass flow rate, pressure, and temperature under cold and hot flow conditions, thus providing unique data suitable for validation studies of the model. Steady and dynamic simulations in the dump combustor show that the model is able to capture several relevant features including fuel flow and inlet velocity transients and flashback. Cold flow results in the can-type combustor show that the model is able to predict a reasonable velocity distribution in a complicated geometry with flow splits.