基于连续方程的河道水流双变量耦合演算模型

摘要

A significant inability of the existing river flood routing models is their limitations to simulate single variable (discharge or water stage).The research proposes a "general bivariate" coupling routing method that improves the universality of Muskingum method and can simulate double variables simultaneously.The proposed model is based on the flow continuity equation and two different forms of river reach storage equation:(1) the storage of a river channel equals the product of the mean cross-sectional area and the river channel length;(2) the storage of a river channel equals the product of the mean discharge of a river channel and the flow travel time.In order to consider the representative of diverse factors,including geographical scope,river channel features,flood magnitude,hydraulic characteristics and et al,the proposed model is tested by observed data of flood seasons which is selected form 16 rivers channels of 4 river basins in China.The rationality of model structure and performance of model simulations are determined comprehensively.When compared with Muskingum routing method,the approach can lead to more accurate simulations and the performance is more stable than Muskingum routing method.The proposed model is more versatile than Muskingum model in real cases.%针对现有的河道水流洪水演算模型只能模拟单一变量(流量或水位)的问题,以水流连续方程和河段蓄水量的两种不同表达形式(蓄水量等于平均过水断面面积与河段长乘积,蓄水量等于河段平均流量与传播时间的乘积)为基础,对马斯京根模型进行了通用性改进,提出了双变量耦合通用演算模型.选取了四大水系(包括内陆河流和入海河流)的16个河段汛期洪水资料进行模型检验,模型验证考虑了地理范围、不同的河段特征和水力特征、洪水量级等因素,全面地检验了模型结构的合理性和模拟实际洪水的有效性.将双变量耦合通用演算模型与传统的马斯京根法进行了效果比较,结果表明双变量耦合通用演算模型的模拟精度高于马斯京根法,模拟效果比马斯京根法稳定一些,而且具有较好的通用性.