Vehicle hydroplaning speed predicted via computational fluid dynamics

Pneumatic hydroplaning has been identified as one of the major causes of wet weather traffic accidents. Therefore, knowledge of potential hydroplaning speeds is crucial in designing roadways to reduce crash risks. It has been shown that the tire inflation pressure is the predominant factor affecting the hydroplaning speed while factors such as the water film thickness also contribute heavily to this phenomenon. A numerical model has been formulated for the simulation of a smooth tire sliding over a flooded pavement using the finite volume method. The current study adopts a generalized methodology that does not need a starting tire load and an inflation pressure, which essentially simplifies the complexity of the model. Alternative turbulence models have been used in the simulation process and model performances have been compared. The model verification has been done with respect to the well-known National Aeronautics and Space Administration (NASA) equation which was developed by previous researchers using experimental findings involving trucks at NASA’s Langley research facility. Predictions of the developed model were also compared with those of other existing empirical and numerical models for a range of water film thicknesses. In addition, the model behavior under changing loads has also been investigated. From the numerical analysis performed it was concluded that the accurate representation of hydrodynamics underneath the tire is crucial for numerically predicting the correct lift force on the tire. Specifically, it was revealed that modeling of turbulence in the flow is essential to obtain a better agreement with experimental results. Additionally, it was shown that changing the tire load has only a minor effect on the hydroplaning speed.