基于圣维南方程组的水位流量单值关系应用

Single-Valued Calculation of the Relationship Between Water Level and Discharge by Using Saint-Venant Equation

水位流量关系在水文预报、水文资料整编以及水文学基础理论研究中有着重要地位,提出使用简单、精度高的计算方法非常重要,而实际河道观测中直接观测流量非常困难,且观测成本高。为了能够准确地从观测的水位值直接得到河道的流量,结合圣维南方程组的连续方程与运动方程,将过水断面简化为矩形断面,引用塞当公式导出了不忽略惯性项时不同比降河流均适用的流量方程,提出了有/无水面比降资料时的绳套形水位流量关系单值计算及推算逐时段流量的方法,并给出了计算步骤。结合白河站实测资料,给出了有/无水面比降资料的绳套形水位流量关系,并将计算值和实测值进行了对比。结果表明:给出的绳套形水位流量方程理论正确,计算简便,精度有保证,可在实际工作中推广应用。

The relationship of water level and discharge is very important for hydrology prediction,hydrology data collection and hydrology basic research. It's necessary to find a simple and high precision computed method. It's very difficult and expensive to get the discharge in the river. In order to get the discharge from the observed water level,this paper put forward the single-valued calculation of the relationship between water level and discharge with and without water gradient by combining continuity equation,momentum equation of Saint-Venant system of equations and Satang formula. It took the cross section of river as a rectangular cross section and derived the rope-shaped discharge equation with not neglect inertia item in different slope. This paper provided the calculated steps. These discharge equations was verified by the measured data of Baihe Station. The results show that the given equation theory of flow-stage is correct. It is also simple and high precision. This discharge equation can be used in practical work.