Lattice Boltzmann Simulations of Micro-Jet Controlled Fuel Inject-or Flow Fields

Next generation combustors must maintain combustion efficiency while consider-ably reducing emissions, such as, CO, NOx and unburned hydrocarbons. A viable methodology is to enhance the fuel-air mixing process so that the initial dense spray regime is minimized and the subsequent mixing between the vaporized fuel and air is maximized. Current investigations of mixing methods using MEMS-based micro-jet injectors have demonstrated a possible active control method-for rapidly increasing the mixing process. However, detailed understanding of the coupling between the MEMS device and the fuel injector is not yet available. In this research, a Lattice Boltemann equation (LBE) method is employed to simulate the flow both inside and outside a synthetic jet actuator. Effect of varying the forcing amplitude and frequen-cies, and different configurations of the synthetic actuators are examined. Analysis of these cases, along with comparison with experiments are carried out to demon-strate the accuracy and efIlciency of this approach. Subsequently, a fuel injector with synthetic jet actuators inside it is used to demonstrate mixing enhancement by these devices.