Application of background oriented Schlieren (BOS) method for visualization of evaporating impinged spray

The background oriented Schlieren (BOS) method for the visualization of impinged evaporating spray is presented to analyze macroscopic spray characteristics and evolution processes. The spray characteristics of dimethyl ether (DME), DME blends, biodiesel and diesel on the impinged wall in a pressurized chamber are effectively visualized for the spray evolution processes, spray depth, and spray area at various elapsed times. The visualization results of impinged spray on the wall by BOS method compared those with the scattering method. It is confirmed that the BOS method is an effective method for measurement and visualization of impinged evaporating sprays. The spray depth for the impinged wall increased with the increase of DME mixing fraction and the evolution patterns showed the stepped increasing due to impinged effect of plane wall.