Experimental investigations on dynamic wave structures of a prefilming atomizer

Abstract

An experimental study was performed on a planar prefilming airblast atomizer to investigate the dynamic wave behavior on a prefilmer. Using a high-speed camera, backlighting visualization and reflection imaging were applied to record the breakup process of the liquid film and the temporary evolution of wave structures. Image post-processing methods were used to obtain the film thickness, surface wave frequency, breakup length, and ligament breakup frequency. Depending on non-dimensional aerodynamic numbers, surface waves on the prefilmer were classified into three mechanisms. In addition, correlations were derived from experimental data and used to predict atomization characteristics. The deviations of surface wave frequency and breakup length were limited to ±10%. These predictive correlations can assist in resolving engineering issues regarding prefilming atomizers.