黄河下游灌区水沙资源动态优化配置模型研究

The water resources and sediment resources are seriously uneven distribution in the irrigation districts of the Lower Yellow River. On the one hand, the abandoned sediment dredged from the cannal and piled up as small hills along the canal and has being disasters for local environment; on the other hand, the sufficient sediment deposited in the upper irrigation canal, retarding the runoff flow fluent and deteriorating the shortage of water resources in the lower area of irrigation district. Therefore, the rational allocation for sediment resources as urgent as the allocation for water resources. Currently, the mathmatical model of sediment allocation coupled with the water resources allocation has needed to be studied deeply. Water and sediment allocation in irrigation area means arranging and distributing the water resources and sediment resources in a fixing area in a given period, which belongs to the category of management and planning. Owing to the target of allocation is in a macro scale, the outcomes of allocation are in static, the measures to achive allocation could be conducted from the hydrodynamics and sediment dynamics in micro scale. The Lower Yellow River irrigation area, which is influenced by lots of human activities, is favorable to be dynamic regulation of water and sediment resources. Under the condition of priority to meet the water demand, the feasible method to implement the coupled of water resources and sediment resources optimum allocation in irrigation districts is, in the general conditions of the optimal allocation of water resources, make full use of water and sediment regulation technology, dynamic allocate the sediment resources in each unit time and each unit area, and enventually configure the resources approaching the optimum in the whole district. The contents of this research item are: Putting forward concept of the dynamic allocation between the sediment resources and the water resources, and study on this new concept theoretical system, Study on the mechanism of dynamic regulation mode, including the mechanism of divied water and sediment from the Yellow River main chanel, capacity of the flow transfer the sediment in the irrigation canal, etc. Exploration of the dynamic alloction mathmatic model which linked the channel hydro dynamic model and resources allocation model, and apply the mathmatic moderl in the irrigation district of the Lower Yellow River.

黄河下游灌区水沙资源分配严重不均：渠首地区水多沙多，泥沙堆积成害；下游地区水少沙少，缺水问题严重。引黄灌区泥沙资源配置与水资源优化配置同样紧迫。目前，灌区水沙资源优化配置数学模型尚需深入研究。 灌区水沙配置是对灌区一定时期内水资源和泥沙资源进行合理的安排和分配，属于管理和规划范畴，配置目标是宏观的，配置结果是静态的；宏观和静态的配置可以从微观和动态上的水流输沙的动力来调控实现。在水资源需求占首要地位要求下，实现灌区水沙资源优化配置可行的方法是在水资源优化配置的总体约束条件下，充分发挥和利用灌区水沙调控技术，在单位时间内，对单位区域的泥沙资源进行动态配置，最终使整个灌区配置趋近最优。 本项目①提出水沙资源动态优化配置概念；②对灌区系统水流泥沙运动规律及调控技术进行深入研究；③结合水流输沙动力学模型与优化配置模型，搭建适用于灌区的水沙资源动态优化配置数学模型。

黄河下游引黄灌区的主要特点是水少沙多，水沙分配不均。灌区水沙资源合理配置是引黄灌溉可持续发展的重要措施。本研究从黄河下游引黄灌区在发展过程中面临的主要水沙问题及形成的水沙分布特点出发，就灌区不同水沙调控模式、水沙配置能力、配置能力指标、水沙资源优化配置数学模型及其在典型灌区优化配置应用进行了研究。取得的主要研究成果如下：.1..提出了黄河下游引黄灌区水沙调控模式。结合不同灌溉类型和泥沙处理方式，以灌区水沙分布特点为依据，提出了沉沙输水模式、输水沉沙模式、分水滞沙模式和输水输沙模式4种水沙调控模式。.2..研究了黄河下游引黄灌区水沙配置能力，建立了配置能力指标。根据资源配置约束要求，提出灌区水沙配置能力定义及表现形式，并分析了黄河下游引黄灌区引水引沙能力，推导了渠道分水分沙能力和分水影响下渠道输水输沙能力表达式，给出了沉沙池容沙能力的计算方法。根据灌区水沙分布现状及配置目标，建立了以集中渠段平均分配量与灌区整体平均量的倍比关系来表示的灌区水量配置能力指标Iw、泥沙配置能力指标Is和泥沙淤积配置能力指标Isd，根据渠系水沙衰减规律，导出了配置能力强弱的判别标准，即Iw=1.5，Is=1.75和Isd=1.0，并根据指标物理意义，计算划分了判别标准等级。.3..建立了灌区水沙资源优化配置模型，并评价了不同模式在不同初始条件下的配置方案。利用目标规划方法，将不同性质的水沙变量转化为同类型偏差变量构造综合目标函数，并结合水沙配置能力等约束方程，建立灌区水沙资源耦合优化配置数学模型，进而求解不同水沙调控模式在水量较均匀条件（Iw=1.5）和水量均匀条件（Iw=1.0）下的配置方案；采用灰色系统评价方法对不同调控模式配置方案进行评价，结果表明，不同模式在水量均匀条件下的配置方案均优于较均匀条件下的配置方案；水量配置初始条件相同时，输水输沙模式最优，分水滞沙模式或输水沉沙模式次之，沉沙输水模式较差。.4..提出了位山灌区水沙优化配置方案和主要调控措施。在全面分析位山灌区引水引沙、水沙分布状况及主要水沙问题的基础上，根据水沙配置能力，利用水沙资源优化配置数学模型，计算并提出了位山灌区水沙资源优化配置方案，并通过与现状水沙分布的对比和评价，提出了实现位山灌区水沙优化配置的综合调控技术措施。