道路表面动水压力的计算和分析  

Calculation and analysis of hydrodynamic pressure on road surface

作　　者：董强柱[1] 李彦伟[2] 石鑫[2] 李志勇[3] 

机构地区：[1]长安大学公路养护装备国家工程实验室,陕西西安710064 [2]石家庄市交通运输局,河北石家庄050051 [3]重庆交通大学土木建筑学院,重庆400074

出　　处：《长安大学学报（自然科学版）》2013年第5期17-22,共6页Journal of Chang’an University(Natural Science Edition)

基　　金：河北省交通科技项目(Y-2012008);中央高校基本科研业务费专项资金项目(2013G1251030)

摘　　要：针对雨天行车轮胎所产生的动水压力易导致水损害和车辆打滑的问题,运用计算流体力学理论建立路表径流条件下的道路-轮胎有限元模型,采用k-ε模型解析紊流闭合方程,VOF模型解析两相流的水流自由表面流动,SIMPLE算法对模型计算域内有限体积中速度-压力的耦合进行离散化,计算了不同轮胎花纹深度、水膜厚度和行车速度下的动水压力,并预测了不同条件下车辆出现'水漂'的临界行车速度。计算结果表明:随着水膜厚度的增加,轮胎所受的动水压力持续增长;当水膜厚度小于花纹深度时,动水压力随车速增长缓慢,当水膜厚度大于花纹深度时,动水压力与车速近似为线性关系;对于小型轿车,路表水膜厚度为8mm时,车速为145km/h时可出现'水漂'现象,水膜厚度为12mm时,出现'水漂'的车速降低为133km/h。Abs Aimed at the fact that hydrodynamic force caused by tires is the main reason for water- damage of asphalt mixture and skid of vehicle in rainy condition, a finite element model of road surface and tires in runoff on road surface was founded using CFD technique; the k-ε model was used to solve the turbulence closure equations; the free surface flow of water in two-phase flow was solved by using VOF option; and the discretization of pressure-velocity coupling for the finite volumes in the domains was computed using SIMPLE algorithm. At last, hydrodynamic force was calculated under different tire tread depths and water film depths and running speeds and the speed for hydroplaning was forecasted in different conditions. The results indicate that the hydro- dynamic force increases gradually with the thickness of water film; the hydrodynamic force in- creases slowly when the water film thickness is less than tread depth of tire, and the linear rela- tionship between hydrodynamic force and speed occurs; to a car, hydroplaning will occur when the thickness of water film is 8 mm and the speed of car reaches 145 km/h; while the thickness of water is 12 mm, the speed for hydroplanning will fall to 133 km/h. 1 tab, 6 figs, 11 refs.

关 键 词：道路工程 动水压力 计算流体力学 有限元 

分 类 号：U416.14[交通运输工程—道路与铁道工程]