MODELING OF PARTICLE WALL INTERACTION AND FILM TRANSPORT USING EULERIAN WALL FILM MODEL

摘要

The growing awareness of pollutant emissions from gas turbines has made it very important to study fuel atomization system, the spray wall interaction and hydrodynamic of film formed on engine walls. A precise fuel spray spatial distribution and efficient fuel air mixing plays important role in improving combustion performance. Cross-flow injection and film atomization technique has been studied extensively for gas turbine engines to achieve efficient combustion. Air blast atomizer is one of these kind of systems used in gas turbine engines which involves shear driven prefilmer secondary atomization. In addition to gas turbine combustor shear driven liquid wall film can be seen in IC engines, rocket nozzles, heat exchangers and also on steam turbine blades. In our work we have used Eulerian Wall Film (EWF) model to simulate the experiment performed by Arienti et al. In the Arienti's experiment liquid jet is injected from a nozzle from the top of the chamber. Droplets shed from the jet surface due to primary and later secondary atomization in the presence of high shearing cross flowing air. Further liquid fuel particles hit the wall to form film, film moves subjected to shear from the gas phase. Liquid film can reatomizes due to subgrid processes like stripping, splashing and film breakup. In current study we have validated Arienti et al. experimental data by modeling complex & coupled physics of spray, film and continuous phase and by accounting complex subgrid processes.