Simulation of Thermal Efficiency and Environmental Pollutant in Combustion Chambers

Abstract

A simulation study was carried out to salvage global environmental pollution challenge posed by NOx in the atmosphere which is often released from incomplete combustion reactions of methane and air. This was done using computational fluid dynamics software package to model three 3-dimensional combustion chambers. The chambers were categorized into symmetric baffled, asymmetric baffled and non-baffled combustion chamber. Methane gas (fuel) and air were the combustion reactants charged into the chambers. The model focused on evaluation of some significant combustion properties at the outlet such as mass fraction of methane, temperature, velocity, turbulence, and mass of NOx released into the atmosphere. Thermal efficiency, percentage combustion, pattern factor and pollution caused by the combustion were among other parameters determined in the model. The baffled symmetric and asymmetric chambers yielded thermal efficiency of 71.1 and 68.05%, respectively while the non-baffled yielded a thermal efficiency of 63.3%. The combustion percentage for the baffled chambers was 8.6 % while the nonbaffled chamber was 5.37 %. Pattern factor for the non-baffled, asymmetric and symmetric chambers were 0.91, 0.70 and 0.66, respectively. The evaluation of pollution caused by combustion results revealed that baffled combustion chambers can give 97 % decrease of NOx pollutant released to the environment from combustion of methane and air. The model results showed that baffled combustion chambers can be used as an economically viable chamber with high thermal efficiency and high reduction of NOx pollutant released to the environment with symmetric system as the best method