基于光电传感器和示踪法的径流流速测量系统的研究

Runoff flow velocity measurement system using photoelectric sensor and tracing method

坡面径流流速是决定土壤侵蚀强度的重要因素，也是坡面侵蚀预报模型考虑的关键问题。采用LabVIEW虚拟仪器，开发了一套室内模拟坡面径流流速测量系统，包括试验台、光电传感器、采集卡及测控软件等。系统以泡沫粒子作为示踪粒子，进行了室内模拟坡面径流流速的测试。结果表明，自行设计的试验台能实现水沙循环使用，在0-400kg／m^3含沙量、0～25。坡面的范围内，该测量系统能够测定径流流速，最大相对误差为2．29％，为坡面径流流速的快速、准确测量提供了一种新的有效的方法。

The velocity of slope runoff flow is an important parameter to evaluate soil erosion, and it is also a key factor in the soil erosion forecast. A runoff flow velocity measurement system based on LabVIEW was developed, which consisted of test-bed, photoelectric sensor, data acquisition card, measuring and controlling software. The experiment was completed in room simulation test-bed using foam particle as a tracer. The result indicates that the test-bed can recycle water and soil. The system measures runoff flow velocity accurately at the scope of 0-400 kg/m^3 and 0-25° of slope gradient. It is found that the greatest relative error of the system is 2.29%. This measurement system provides a new, valid method for speedy and accurate measurement of runoff flow velocity.