Flow physics and chine control of the water spray generated by an aircraft rigid tire rolling on contaminated runways

During the take-off and landing of aircrafts from/on water-contaminated runways, the tire-generated water spray can endanger flight safety, such as engine spray ingestion and spray impingement drag. In this paper, the flow physics and chine control of the spray generated by an aircraft rigid tire are studied by the Smoothed Particle Hydrodynamics (SPH) method. The SPH method is validated by a NASA experiment. The forming and developing progresses of the front and side sprays are described in detail. It is found that the parabolic stripe of initial ejected particles at a given time is the boundary between the spray source region and the non-disturbed region in water film, and the stripes at any time are similar. The effects of tire speed and water film depth on spray angles are evaluated. The chines can effectively control the spray angles by reducing the vertical velocity component of the ejected particles and increasing the lateral component. The arc chines are more effective in controlling the spray than the linear chines.