【作者】 周秀彩；

【导师】 陆伟刚； 陈建康；

【作者基本信息】 扬州大学 ， 水利水电工程， 2004， 硕士

【摘要】 我国是一个水资源十分短缺的国家，近年来又由于工业的发展，人类居住的相对集中，大量有害于人类和其他生物的工业废物、农业废水和生活污水排入河流，使有限的水资源受到严重污染。污染物通过在水体中溶解扩散以及随流输移而扩大影响范围。为了保护环境，防止污染扩散的危害，因此，从流体力学和动力学方而着手研究污染物在河道中扩散的水力学特性是很有意义的。 污染物排入水体后，与水体的混合过程可分为三个阶段：第一阶段为垂向混合阶段，主要在水深方向混合；第二阶段为掺混阶段，以垂向充分混合起至河流横向丌始充分混合为止；第三阶段为完全混合阶段，污染物在横断面上开始充分混合后的区域。 首先，本文对近二十年来污染物扩散的水力学理论进行了概括总结，并利用流体力学理论推导了部分公式。其次，从河道系统整体出发，运用污染物在水体中扩散的水力学特性，对河道垂向、横向、纵向的污染物扩散过程进行研究，着重分析了垂向、横向扩散的平面二维流场的计算及纵向扩散的一维流场的计算，并对当前的污染物扩散的水力学理论公式进行了简化，建立了实用性很强的污染物扩散的数学模型，并针对具体数学模型进行了计算求解及程序编制，使得工程使用更加方便、适用。本文的研究旨在揭示污染物扩散过程中，它的浓度在平面流场中随时间的变化规律，从而可以预报纳污水域中水体受污染的程度，为水质的保护，水环境评价，水资源的开发和利用提供依据。 本文还介绍了河道的环境容量，概括总结了其理论计算公式，它是不同使用用途的水体所能容纳污染物总量的依据。更多还原

【Abstract】 China is short of water resources, in addition, because recently industry is rapidly developed and people live relatively in mass, much of industrial sewage, agricultural effluent and domestic wastewater that do harm to human being and other creature drain into river, which make limited water resources polluted. Pollutant extends its incidence .by diffusing after dissolving and being carried by water flow. To protect environment and prevent the jeopardize of pollutant, working over hydraulic characteristic of pollutant diffusing is very content from the aspect of hydrodynamics and hydrokinetics.Mixed process of pollutant and water has three moment in the water: the first moment is vertical mixing, primary mixing in depth; the secondt moment is impure mixing, beginning vertical replete mixing and terminating transverse replete mixing, the third process is replete mixing, beginning transect replete mixing.In this paper, diffused hydraulic theories for twenty years recently are generalized, and parts of formulas are derived applying hydrodynamics theory. Based on the holistic system of waterway, applying the diffused hydraulic characteristic of pollutant, diffusing process of pollutant are studied in the river of vertical, abeam and portrait, stress is to analyze the calculation of complanate flow field in two dimension of vertical and abeam and the unidimensional portrait one, exiting hydraulic academic formulas are simplified, mathematical models in point are established, and numerical calculation methods are carried out to solve and programme to more convenient and applicable for the engineers. All is to post the variational rules between concentration and time of pollutant, which can forecast contaminative degree and provide criterion for water quality protection, aquatic environment evaluating and water resources exploiting.Environment capacity is introduced here and theoretic summarized, which is thereunder for different water using purpose containing pollutant gross.更多还原