Controlled Combustion Of Toxic Waste Materials In A Compact Dump Combustors

A large-eddy simulation (LES) model was developed to simulate waste injection and combustion in a compact dump combustor. The configuration and the dimensions of the modeled was chosen to correspond identically to the experimental device. The first phase of the study investigated non- reacting fuel-air mixing in the combustor. The fuel (here considered to represent the waste) was injected using both passive and active control of the injection process. The pressure field in the combustor was used as a sensor and the fuel was injected both in-phase and out-of-phase with the local (at the dump plane) pressure oscillation. Results showed that when fuel (or waste) is injected in-phase with the local pressure oscillation (that is when the pressure is higher than the mean). then significantly enhanced entrainment of the fuel into the large coherent structures in the shear layer can occur. Engulfment of the waste into the vortices can increase the waste residence time in the combustor and hence increase its consumption. Results with and without heat release confirm this observation - results are in good agreement with the observation in the laboratory.