【作者】 熊烈强；

【导师】 陈明昭；

【作者基本信息】 武汉理工大学 ， 轮机工程， 2003， 博士

【摘要】 智能运输系统(Intelligent Transportation System，简称ITS)是将先进的信息技术、通信技术、控制技术、传感技术和系统综合技术有效地集成，并应用于地面运输系统，从而建立起大范围内发挥作用的、实时、准确、高效的运输系统。在智能运输系统(ITS)中，交通流理论研究是基础研究内容之一。 交通流理论是运用物理学和数学的方法来描述交通特性的一门边缘科学，是发展中的科学，目前还没有形成完整的理论体系。在道路通行能力研究中，交通流理论的发展和完善体现了其研究的深度和广度。但由于交通现象的复杂性，到目前为止，研究还局限于经验方法或半经验半理论方法，而且各国有各自的一套方法，没有普遍意义。还没有建立起一套得到公认的理论体系。 本文运用流体力学的研究方法，建立了能够应用于通行能力计算及服务水平评价的交通流理论。具体工作如下： (1)综合分析了交通流中驾驶员的交通特性、车辆的交通特性、道路的交通特性、交通流的宏观参数和微观参数，提出了新的交通流连续性假设，定义了衡量交通流压缩性的压缩系数和弹性系数，分析了各种速度-密度模型所对应的压缩系数。 (2)阐述了研究交通流的欧拉方法；应用物理学中的质量守恒定律、牛顿第二定律、动量定律等，建立了交通流的连续性方程、欧拉方程和动量方程；提出了相对粘性假设，在欧拉方程中引入相对粘性阻力项，建立粘性交通流的运动微分方程，并采用线性模型和定流量模型予以验证。 (3)建立了适应ITS的交通流参数之间的关系。与传统模型比较，引入了自由流密度作为模型中的参量。该模型能够与实测数据较好拟合。 (4)根据运动微分方程的系数将交通流模型进行分类，采用特征线法对各种模型进行了分析和预测。 (5)通过两个算例和一个实例表明，本文模型能够反映交通流的基本特性。武汉理工大学博士学位论文在数值实验中，需要识别的参数只有最大波速，与其它模型比较，使用更加方便。 (6)提出了用最大波速计算通行能力的公式。对广深高速公路、广佛高速公路和沪宁高速公路的实际通行能力进行了计算;采用HCM20OO的数据，预测了不同气候条件下的理论通行能力。采用本文的公式计算实际通行能力时，只需要根据实测数据确定最大波速，而低密度的数据足以确定最大波速。因此，即使只测到了低密度的数据，仍然可以较准确地计算其实际通行能力。 (7)提出了用无量纲相对交通压力评价道路路段服务水平的指标体系。并对统计汇总的广深高速公路和广佛高速公路实测交通状态进行了“静态”服务水平评估;根据5分钟时段实测数据，对广佛高速公路和沪宁高速公路1车道和2车道进行了“动态”服务水平模拟监测。本文的指标体系是能够适应智能交通系统高速大流量要求的、统一、连贯的指标体系。更多还原

【Abstract】 Intelligent Transportation System (ITS) assembles advanced information technology, communication technology, control technology, sensor technology, and system integration technology efficiently, and applies them to the ground transportation system. ITS constructs an effective in large-scale, real time, exact, and efficient transportation system. In the research of ITS, traffic flow theory is one of the basic.Traffic flow theory is a frontier and developing science that seeks to describe the characteristic of traffic in mathematical and physical way. At present, there isn’t an integrated theoretical system. In the research of highway capacity, the development and perfection of traffic flow theory has incarnated the deepness and width in research. Capacity research is limited to experiential or semi-experiential method so far because of the complexity of traffic behavior. Each country has respective method that isn’t prevalent. There isn’t a set of accepted theoretical system.In this paper, we study traffic flow from the viewpoint of hydrodynamics, and set up the traffic flow theory that can be used to calculate the highway capacity and judge the level of service. The research and contribution in detail are introduced as follow:(1) The driver characteristics > motor vehicle characteristics , road characteristics, macroscopic and microscopic flow parameters are analyzed. A new traffic flow continuum hypothesis is proposed. The compression index and elasticity coefficient are defined. Compression indexes for some speed-density are calculated.(2) The Eulerian description is expounded in researching traffic flow. Conservation of mass, second Newton’s law, and momentum law are introduced into traffic flow to set up traffic continuity equation, Euler’s equation, and momentum integral equation. The relative viscosity hypothesis is put forward andintroduced in Euler’s equation to establish viscosity momentum differential equation. The speed-density constant model and Greenshields’ speed-density linear model are adopted to verify the hypothesis.(3) Relationships among traffic flow parameters suitable for ITS are obtained. Comparing with the traditional models, relationships include free flow density, and coincide with the field data observed on freeways.(4) According to the coefficient in momentum differential equation, some traffic flow models are classified, analyzed and predicted by means of characteristic curve method.(5) As to the numerical experiments, three cases are chose to testify the applicability of the model in the paper. The numerical cases show that the model can reasonably describe the nature of traffic flow. In numerical simulations, the maximum wave velocity is the only identification parameter. With the traditional models, the model in the paper is more convenient.(6) A highway capacity calculating model for basic sections is set up by using the maximum wave velocity. Actual capacities of Guangzhou-Shenzhen, Guangzhou-Foshan and Shanghai-Nanjing freeway are calculated. Using the data from Highway Capacity Manual 2000, the capacities under the different weather are predicted. Identifying the maximum wave velocity, the actual capacity can be calculated. The maximum wave velocity can be determined upon the data in low density. So, even if having the data in low density, the actual capacity can be calculated correctly.(7) By non-dimensional traffic pressure, an evaluating index system for level of service of highway is set up. According to the statistical data, the LOS’ of ’static state’ of Guangzhou-Shenzhen and Guangzhou-Foshan freeway are evaluated. According to the 5min data, the LOS’ of ’real-time state’ of Guangzhou-Foshan and Shanghai-Nanjing freeway are evaluated. The index system is a uniform and coherent index system of grading service for different highways, and suitable for the purpose of high speed and large flow of ITS.更多还原