基于需水过程的灌区实时渠系优化配水模型及应用

马建琴 赵子伟

摘 要：针对灌区灌溉规划用水与作物实时需水不匹配的问题，建立了基于作物需水过程的渠系实时优化配水模型，以下级渠道配水结束时间为决策变量，以灌区时段缺水率之和最小和渠系输水损失量最小为目标，采用遗传算法求解模型。结果表明：与经验法编制的配水方案进行对比，各级渠系配水时间搭配更加合理，渠道配水流量波动小;灌水量配置更符合作物实际需水要求，与作物实时需水耦合度更高，灌区各时段缺水率之和减小了13.6%，配水时间减少了2.5 d，渠系输水损失量占比减少了6.3个百分点，渠系配水达到了省时高效、节约用水的目标。

关键词：实时渠系配水;优化配置;需水过程;灌溉制度;时段缺水率

中图分类号：S274.3;TV146 文献标志码：A

doi：10.3969/j.issn.1000-1379.2021.05.030

Abstract： Aiming at the issue that the existing water distribution plan in irrigation area cannot meet the actual operation of canal system and the real-time water demand of crop growth and development， a real-time optimal water distribution model of canal system based on crop water demand process was established. The end time of lower-level canal water distribution was the decision variable， the objective function was the minimum sum of water shortage rate and the minimum water loss of canal system and used the genetic algorithm to solve the model. The results show that compared with the water distribution scheme prepared by the empirical method， the water distribution time of all levels of canal system is more reasonable and the fluctuation of water distribution flow is small; the irrigation allocation is more in line with the actual water demand of crops， and the coupling degree with the real-time water demand of crops is higher， the water shortage rate of irrigation area is reduced by 13.6%， the water distribution time is reduced by 2.5 days and the water transfer loss of canal system is reduced by 6.3%. The canal water distribution achieves the time-saving， efficient and water-saving goals.

Key words： real time canal system water distribution; optimize configuration; water demand process; irrigation schedule; water shortage rate in period

目前我國大部分灌区在制定用水计划时仍按经验方法手工编制，这会导致渠系输水时间较长、配水流量小和灌溉水资源浪费等问题。在农业灌溉水量本就不足的情况下，农田灌溉水利用系数仅有0.548[1]，远低于发达国家水平，农业用水形势十分严峻。如何通过科学手段分配灌溉水量，减少输水损失，提高灌溉水利用系数，是目前灌区管理工作中急需解决的问题。

国内外学者为解决渠系优化配水问题已经做了大量研究，并提出多种优化配水模型[2-3]。根据研究目标可分为两大类：第一类以经济效益为主体，研究目标为灌溉管理部门收益最大[4]、作物产量最大[5]等;第二类以灌区渠系运行为主体，研究目标为配水时间最短[6]、上级渠道配水流量平稳[7]、输水损失量最小[8]等。……