Thermal Decomposition of a Single AdBlue® Droplet Including Wall–Film Formation in Turbulent Cross-Flow in an SCR System

摘要: Apart from electric vehicles, most internal combustion (IC) engines are powered while burning petroleum-based fossil or alternative fuels after mixing with inducted air. Thereby the operations of and evolve in a turbulent flow environment created during intake phase then intensified by piston motion influenced shape chamber. In particular, swirl turbulence levels existing immediately before affect evolution these processes determine engine performance, noise pollutant emissions. Both characteristics bulk pattern cylinder strongly affected inlet port valve design. present paper, large eddy simulation (LES) is appraised applied to studying fluid around single IC-engine as represented so called magnetic resonance velocimetry (MRV) bench configuration relatively Reynolds number 45,000. To avoid an intense mesh refinement near wall, various subgrid scale models for LES; namely Smagorinsky, wall adapting local (WALE) model, SIGMA, dynamic one equation models, employed combination appropriate function. For comparison purposes, standard RANS (Reynolds-averaged Navier–Stokes) k- e model also used. terms global mean error index velocity results obtained all at first it turns out that show similar predictive capability except Smagorinsky experiences higher normalized absolute (nMAE) once compared MRV data. Secondly, based on cost-accuracy criteria, WALE used fine ≈39 millions control volumes, averaged showed excellent agreement between LES measurements, revealing high prediction suggested tool flows. Thirdly, across curtain clearly featured back resulting speed jet middle. Comprehensive data generated carry statistical analysis (1) morphology passage relying anisotropy map, (2) integral scales along intake-charge stream, (3) properties such kinetic energy, its intensity within critical zone intake-port length, further transpires responsible in-cylinder turbulence.