River Discharge Calculator

River Discharge Calculator is a user friendly program that implements a numerical method to improve the efficiency of river discharge measurement, proposed in the accompanying preprint submitted to the Journal of Hydrological Engineering (ASCE), May 2016. In this work we propose a simple computational scheme with the pragmatic purpose of augmenting the efficiency of river discharge measurements. Observing the functional form of the velocity profile versus depth, applying polynomial regression for each vertical, and finally interpolating between the verticals, we arrive at a continuous approximation for the velocity across the entire vertical section, which turns out to be rather robust to removal of individual measurement points. In particular, numerical data analysis shows that the number of measurements can be significantly reduced without a significant loss of precision of the discharge estimate. This procedure has been tested on the data obtained experimentally on Exu, Capibaribe and Ipojuca rivers, in the state of Pernambuco, northeast of Brazil, with different stream flow patterns demonstrating multiple local velocity maxima on and below the surface.

河流流量计算器（River Discharge Calculator）是一款用户友好型程序，实现了一种数值方法以提升河流流量测量效率，其相关方法已发表于2016年5月提交至美国土木工程师学会（ASCE）旗下《水文工程期刊》（Journal of Hydrological Engineering）的配套预印本中。本研究提出了一种简洁的计算方案，核心务实目标为提升河流流量测量的整体效率。通过观测流速沿水深分布的函数形式，对每个垂向断面开展多项式回归（polynomial regression），随后在各垂向断面间进行插值运算，最终可得到全断面流速的连续近似分布。该方法对单个测量点的移除具备较强的鲁棒性。尤为关键的是，数值数据分析表明，在流量估算精度无显著损失的前提下，可大幅缩减所需的测量点数量。本流程已通过巴西东北部伯南布哥州（Pernambuco）境内埃苏河（Exu）、卡皮巴里贝河（Capibaribe）与伊波茹卡河（Ipojuca）的实测实验数据完成验证，这些河段存在多种水流模式，且在水面及水下存在多个局部流速峰值。