Table3_Adaptive design of tipping bucket flow meters for continuous runoff measurement.PDF

Introduction: Runoff measurement and monitoring is a laborious, time-consuming, and costly task. Additionally, common runoff monitoring usually primarily provide water level, requiring information on the stage-discharge relation. Automatic equipment such as flow meter tipping bucket (TB) is a potential option to simplify and provide continuous runoff monitoring in small catchments. However, a proper description of how to size and adapt the design under different flow conditions is still lacking.
Methodology: In this paper we present a novel standardized framework for the design of TB that can be used for low-cost and real-time runoff monitoring under many different conditions. The framework consists of an estimation of the runoff peak rate using the rational equation and a volumetric capacity estimate of the cavity based on runoff rate, operation speed, and inclination angle of TB when at resting position. The proposed framework was implemented in a case study where four TBs were designed for continuous runoff monitoring from experimental plots (100 m2) with different land use (sugarcane, soybean, and bare soil).
Results: During field tests (five months), the designed TBs had a recovery rate of actual runoff ranging from 61% to 81% and were able to capture features poorly studied (starting/ending time and peak flow) that have potential importance in hydrological models.
Discussion: The proposed framework is flexible and can be used for different environmental conditions to provide continuous runoff data records.

引言：径流测量与监测是一项费力、耗时且成本高昂的工作。此外，常规径流监测通常仅提供水位数据，还需获取水位-流量关系信息。翻斗式流量计（tipping bucket, TB）等自动设备是简化小流域径流监测、实现连续径流监测的潜在方案，但目前仍缺乏针对不同流量条件下如何确定设备尺寸并适配设计的完整说明。
研究方法：本文提出了一种新颖的标准化翻斗式流量计设计框架，可在多种场景下实现低成本、实时的径流监测。该框架包含两部分：一是利用推理公式估算径流峰值速率，二是基于径流速率、翻斗静止时的运行速度与倾角，估算翻斗腔体的容积。本研究通过案例验证了所提框架：针对甘蔗地、大豆地与裸地共4种不同土地利用类型的100平方米试验地块，设计了4台TB用于连续径流监测。
结果：在为期5个月的野外试验中，所设计的TB对实际径流的回收率介于61%至81%之间，且能够捕捉到此前研究较少、对水文模型具有潜在重要性的特征（起涨/退水时间与峰值流量）。
讨论：所提出的框架具备良好灵活性，可适配不同环境条件，为径流监测提供连续的数据集记录。