A three-dimensional surface water droplet impingement characterization method based on Eulerian streamlines

The computation of droplet impingement characteristics on three-dimensional surface is the primary task for ice accretion analysis and anti-icing/de-icing system design for an aircraft and its engine. To overcome the shortcomings of the traditional Eulerian method and Lagrangian method, a streamline-based Eulerian method was established to obtain three-dimensional surface water droplet impingement characteristic. This method only solves the momentum equation to derive the velocity distribution, and does not require calculating the droplet continuity equation. Droplet streamlines are generated via backward integration from the vertices of the three-dimensional surface mesh, allowing impingement characteristics to be calculated without predetermination for droplet release locations or tracking a large number of droplet trajectories. The proposed method is applied to compute droplet collection efficiencies on a three-dimensional sphere, a spinner, and an engine inlet. The results show high computational efficiency and good agreement with the data in the literature, thereby confirming the feasibility and effectiveness of the streamline-based Eulerian method for three-dimensional droplet impingement analysis. This work can provide reference for the ice accretion analysis and anti-icing/de-icing system design of aircraft and engines.