Computational Parametric Study of Fuel Distribution in an Experimental Trapped Vortex Combustor Sector Rig

Numerical simulations are performed to predict the flow properties in a liquid spray droplets fueled Trapped Vortex Combustor (TVC) sector rig. The quantities studied include aerodynamics, pressure drop, spray droplets trajectories, evaporation, mixing and combustion, and combustor exit temperature distributions. Previous numerical simulations of this TVC configuration have identified basic flow patterns and performance characteristics, and were generally in good agreement with experimental data. In the current effort, more detailed investigations were performed to understand the sensitivity of the TVC combustor to variations in the liquid fuel injection parameters. The computational model is described, including combustor geometry, boundary conditions for all combustion and cooling air injections, and spray droplets inlet conditions. A key finding is that liquid fuel injection boundary conditions for different types of downstream flows (cavity, high velocity cross flow) require different treatments, even though similar fuel injectors are used. This is evident in the large differences observed in the combustor exit plane pattern factor due to only minor differences in the fueling schemes. Combustor exit temperature profile strongly affects the design for turbine durability. With small changes in the temperature distribution, design modifications for the first turbine vane cooling schemes are required.Copyright © 2004 by ASME