STUDY ON THERMODYNAMIC COUPLING BEHAVIOR OF NON-NEWTONIAN DEICING FLUID DROPLETS IMPINGING ON SOLID WALLS AT LOW TEMPERATURE

Icing on key aircraft parts is one of the major hidden dangers of flight safety in winter. To eliminate the hidden danger caused by icing, deicing liquid jet deicing is the most common deicing operation method in most airports in our country. The deicing liquid jet is sprayed on the surface of the fuselage to melt the ice and snow of the aircraft skin, and then the film is applied on the surface of the fuselage, which can inhibit the accumulation of ice in the fuselage for a certain period. Deicing fluid is a typical non-Newtonian fluid, and its film distribution characteristics are affected by various factors. This paper studies the film distribution characteristics of Type II deicing fluid impacting aluminum plates and relies on commercial code FLUENT simulation software to build a droplet wall impact model to analyze the data of droplet spreading and rebound under different droplet diameters and different initial velocities. The high speed camera is used for comparative analysis and verification. The coupling effect mechanism of droplet physical property parameters on droplet wall impact behavior and spreading film behavior was revealed, which provided theoretical guidance for airport deicing operation parameter regulation and accurate determination of deicing fluid retention time. Under the same initial conditions, the larger the initial velocity of the droplet, the larger the kinetic energy of the droplet, the larger the maximum dimensionless diameter of the droplet, and the larger the length of the spreading film. The larger the droplet diameter, the larger the droplet falling inertia, the larger the maximum dimensionless diameter, the smaller the thickness, and the longer the spreading film.