No abstract

No abstract

Tire tread pattern is a crucial parameter to prevent hydroplaning. In this study, numerical modeling was used to investigate tire hydroplaning based on flow–structure interaction. The empirical model of hydroplaning speed published in the literature was used to validate the computational model. Analysis of water flow velocity and turbulent flow energy revealed that lateral grooves of the tire significantly influenced water drainage capacity. Based on the relationship between water flow vector and lateral groove shape, a combination of Kriging surrogate model and simulated annealing algorithm was used to optimize lateral groove design to minimize hydrodynamic lift force. Four geometry parameters of lateral grooves were selected as the design variables. Based on design of experiment principle, 12 simulation cases based on the optimal Latin hypercube design method were used to analyze the influence of design variables on hydrodynamic lift force. The surrogate model was optimized by the simulated annealing algorithm to optimize tire tread pattern. The results indicated that at the same water flow speed, the optimized lateral grooves can reduce hydrodynamic lift force by 14.05% and thus greatly improve safety performance of the tire. This study proves the validity and applicability of using numerical modeling for solving the complex design of tire tread pattern and optimization problem.

No abstract

Hot in-place recycling (HIR) has been adopted in pavement engineering because of its low financial cost and lower consumption of nonrenewable material. At present, infrared heating is the most common heating method in HIR, while microwave heating has been proposed as an alternative to it recently. This study investigated and compared the characteristics of microwave and infrared heating by laboratory experiments and numerical modeling. Laboratory tests were first conducted to determine thermal parameters of asphalt mixture and calibrate electromagnetic parameters based on numerical simulation. Two numerical models of microwave and infrared heating under field conditions were further established for analyzing the heating characteristics, including the temperature distribution, heat transfer rate, and energy consumption. The results show that infrared heating can only heat the pavement at shallow depth, while microwave heating can heat the pavement surface and the materials at greater depths to high temperatures. An increase in power was found to enhance the efficiency of microwave heating but to maybe reduce that of infrared heating. Moreover, under the same power, microwave heating needs much less time and energy than infrared heating to reach the same temperature. Microwave heating shows great potential to be applied for HIR of asphalt pavement with the increased recycling depth.