Simulation of icing calculation based on VOF model for wheel spray and landing gear water accumulation

Aircraft interacts with the ground through landing gear system, while taxiing down the runway.Under rain or snow conditions, water film splashed by aircraft tires during taxiing on water-covered runways adheres to the landing gear, leading to ice accretion under low-temperature conditions, which may directly compromise aircraft takeoff and landing safety. Due to the substantial resource consumption required for experimental investigation of this problem, numerical simulation was employed to model the phenomenon.The water film icing process can be divided into two main stages: the formation of water film on the landing gear caused by tire spray, and the subsequent icing and heat transfer process of the splashed water film on the landing gear, this study conservatively simplifies the tire spray phenomenon as a typical liquid-solid two-phase coupling problem. A Finite Volume Model simulating water accumulation dynamics on landing gear tires was developed in Fluent software, based on extreme runway water accumulation conditions and extreme navigation weather scenarios during takeoff of a domestic civil aircraft model. The model incorporates coupled tire-water film-landing gear interactions. The VOF (Volume of Fluid) model and mesh motion are employed to calculate the water film thickness on the landing gear. A conservative thermodynamic equilibrium equation is then constructed based on boundary conditions to estimate the ice accretion thickness. The article analyzed the influence of external factors (aerodynamic drag, gravitational force, etc.) on water film thickness. The calculation results indicate that a conservative estimation of ice accretion derived from water film thickness does not compromise takeoff and landing safety, thereby validating that under rainy or snowy weather conditions with water accumulation on the runway, the conservative maximum icing thickness resulting from wheel spray water and landing gear water accumulation during aircraft taxiing will not exceed a level sufficient to pose a threat to aircraft takeoff and landing safety.