基于Nagel-Schreckenberg交通流模型的演化规则,建立了路口等距分布的主干道交通流模型,在开放性边界及路口以同步红绿灯控制的条件下对交通流进行了数值模拟.分析结果发现:主干道的通行能力由路口的通行能力决定;低密度时,流量与路口数目无关,利用平均场方法,可算出平均速度随绿灯周期变化的极值位置;高密度时,流量与路口数目有关,通过调整交通灯周期,可使主干道处于最佳交通状态.
Based on the Nagel-Schreckenberg model, a traffic model for an arterial road with equal-distance-distributed intersections is established. The traffic flow is numerically simulated under the open boundary condition and the control of red and green lights. It is found from the results that the capacity of the arterial road is determined by the capacity of the intersection. For small densities, the flow has no relation with the number of intersections. Moreover, the rule of variation of the maximum point of average velocity with the green-light period is obtained with the mean-field method. On the contrary, the number of intersections plays a crucial role in the flow at larger densities. The arterial road can achieve optimal traffic state via regulating the period of traffic lights.