关于交通流中扰动传播和发展的数值模拟

ON THE NUMERICAL SIMULATION OF PERTURBATION'S PROPAGATION AND DEVELOPMENT IN TRAFFIC FLOW

针对不同拥挤程度交通流中扰动的传播和发展,进行了系统的数值模拟研究．讨论了PW模型、一维管流模型、单侧传播模型等几种典型交通流模型的不同特征；指出了不同差分格式对数值结果的影响；也分析了数学模型中不同形式的平衡函数的作用．结果发现在适当的数学模型、平衡函数和离散格式下,能够对交通流中扰动的传播和发展,特别是扰动波的传播速度,取得与实际测量数据相当接近的模拟效果．建议了分别适用于不同密度交通流的计算格式．

The propagation and development of perturbations in various density traffic flows are numerically simulated. The studies include the characteristics of some traffic flow models such as PW model, 1-d pipe fluid model and the unilateral propagation model, the effects of equilibrium functions in the models, and the influences of difference schemes on the numerical results. It is found that we can obtain results quite close to the measured data by using the appropriate traffic model, equilibrium function and difference scheme for the traffic perturbation problems, especially the propagation speed of the perturbation waves. A group of calculation schemes suitable to various density traffic flows are proposed.