Wind-Driven Runback Characteristics of Newtonian and Non-Newtonian Deicing Fluids Pertinent to Aircraft Ground Anti-/De-icing

A comprehensive experimental campaign was conducted to characterize the transient runback process of the aircraft deicing fluids over a flat surface as driven by boundary layer airflows pertinent to aircraft ground anti-/de-icing. The experimental study is conducted by leveraging a low-speed wind tunnel available at Iowa State University to generate a boundary layer airflow over a flat test plate mounted horizontally along the bottom wall of the tunnel test section. Two kinds of most-commonly-used deicing fluids, i.e., Newtonian Type-I deicing fluids and non-Newtonian shear thinning Type-IV deicing fluid, are used as the working fluids for the experimental study. In addition to using a high-speed imaging system to record the dynamic wind-driven runback process of the deicing fluids, a novel digital image projection (DIP) system is also utilized to achieve non-intrusive, time-resolved measurements of film thickness distributions of the wind-driven deicing fluid flows over the test plate under different test conditions. A theoretic analysis was also performed to correlate to the experimental study to gain further insight into the underlying physics for a better understanding of interactions among the complicated multiphase flow system (i.e., airflow interacting with Newtonian Type-1 and non-Newtonian shear-thinning Type-IV fluids).