Droplet trajectory model for icing collection efficiencies

A numerical model has been developed to calculate ice accretion characteristics of two-dimensional bodies in a potential flow field. Particle trajectories are calculated in a potential flow field computed for the bodies of interest. The potential flow computation technique employs a distribution of sources, sinks, and/or vortices along the body surface.

The governing equations of motion of droplets in the flow field are integrated by Adams-Moulton predictor-corrector method with a variable time step to yield the particle trajectories. With the trajectories known, the location of droplets impinging on the body are determined, and then the local and total collection efficiency are determined.

A computer program is developed for calculating the particle trajectories, the impingement limits, the local collection efficiency, and the total collection efficiency. The program utilizes the existing potential flow programs to provide numerical solutions for airfoils (with tunnel walls or without walls) and two-dimensional inlet with single-sized or multi-sized droplet distribution.