Numerical simulation of critical hydroplaning speed of aircraft tire under wet pavement condition

A fluid-solid coupling analysis model of aircraft tire and wet pavement based on CEL algorithm was developed by using ABAQUS. The expressions of hydrodynamic pressure of tire contact and vertical supporting force of pavement were derived. The taxiing conditions between aircraft take-off and landing process were compared. The concepts of upper and lower limit solutions of critical hydroplaning speed were proposed. The features of static deformation and dynamic hydroplaning of tire model were verified. The influence rules of tire pressure, tire pattern and water-film thickness were discussed. The contact area and distribution of hydrodynamic pressure for tire were analyzed. Simulation result indicates that the tire contact area is 0.076 m2 under axle load of 76.6 kN, the vertical deformation at the centre of tire is 3.27 cm, and the critical hydroplaning speed is 128.5-222.4 km·h-1, which is in consistence with the result of NASA's tire hydroplaning test. Therefore, the rationality and feasibility of simulation model are proved. When tire pressure is 1 140 kPa, the critical hydroplaning speed of aircraft tire under decelerating impact is 163 km·h-1 and lower than upper limit of accelerating impact (226 km·h-1), the tire contact area obviously reduces, and the supporting force from the pavement to the tire is less than 10% of wheel load. In comparison with the calculation result of NASA's empirical equation, the lower limits of critical hydroplaning speed under decelerating impact are more conservative within the scope of tire pressure from 450 kPa to 1 109 kPa, and the difference is 30-70 km·h-1. The drainage effect of radial tire pattern can reduce the peak value of hydrodynamic pressure at the leading edge of aircraft tire and increase the tire contact area. The critical hydroplaning speed of aircraft tire with tire pattern under decelerating impact increases by 26.9%-28.8% comparing with the speed of smooth tire, and the amplification is twice as much as that of accelerating impact. As the water-film thickness increases from 3 mm to 13 mm, the upper and lower limits of critical hydroplaning speed of aircraft tire respectively reduce by 85 km·h-1 and 43 km·h-1 when the tire pressure is 1 140 kPa. In case of lower tire pressure and thicker water-film, the lower limit of critical hydroplaning speed is merely 127 km·h-1 under decelerating impact and lower than most aircrafts' landing speeds 205-250 km·h-1, so the risk of hydroplaning accident increases. © 2017, Editorial Department of Journal of Traffic and Transportation Engineering. All right reserved.