岔巴沟流域次暴雨产流无量纲模型

Event-based dimensionless models for runoff of Chabagou watersheds

为了建立小流域次暴雨产流预报模型,在岔巴沟流域选取大小不同的4个小流域10a水文资料,分析降雨、地貌等因素对流域产流的影响,选取主要因素最大30min雨量、最大30min雨强、流域沟道比降、流域面积和流域狭长度。用无量纲参数和逐步回归分析的方法估计模型参数,得到了岔巴沟流域次暴雨产流无量纲模型,用模型预报结果与实测结果对比,模型预报精度为70%。结果表明,所建立的模型具有参数少、结构简单、量纲和谐、物理意义明确的特点,可为流域产流模型进一步研究提供参考。

In order to establish the prediction models of the event-based runoff in small watersheds,the observed event-based runoff data of 10 years from 4 Chabagou watersheds were used to analyze the effects of rainfalls and landforms on runoff. It was found that such factors as the maximum rainfalls and intensities in 30 minutes,the gradient of main channels,the areas of watershed,and the ratios of watershed lengths to widths were key factors which affect runoff. Dimensionless parameters and step-wise regression were used to quantify the parameters of the event-based runoff model. The established model used few parameters with simple structure. The featured with clearly defined physical meanings with 70% of prediction accuracy,which could supply a basis for further research of models for watershed runoff prediction.