Comparison of the Viscous Liquids Spraying by the OIG and the Oil Configurations of an Effervescent Atomizer at Low Inlet Pressures

In this work we studied the influence of the fluid injection configuration (OIG: outside-in-gas, OIL: outside-in-liquid) on the internal flows and external sprays parameters. We sprayed the viscous aqueous maltodextrin solutions (μ = 60 mPa·s) at a constant inlet pressure of the gas and the gas to the liquid mass flow ratio (GLR) within the range 2.5 to 20%. We found that the fluids injection has a crucial influence on the internal flows. The internal flows patterns for the OIG atomizer were the slug flows, the internal flow of the OIL device was annular which led to the significant improvement of the spray quality: Smaller droplets, faster atomization, fewer pulsations.