复杂管道条件下的流速分布和流量的准确测量对掌握其流速分布规律及其应用均具有重要的意义。 提出了一种激光自混合测量矩形管道流体层流流速分布和流量的方案。在激光自混合和矩形管道层流流 速分布理论的基础上,分析了矩形管道内流体层流运动时的激光自混合信号频谱特征,得到了矩形管道 层流流速分布特征和流量值。实验测量的矩形管道流速测量值平均相对误差为2.7%,流量值相对误差 在2.0%以内,实验结果与理论相一致。

Accurate measurement of fluid-velocity profile and flow rate in complex duct is important to master the velocity distribution law and its application. A scheme of measuring the fluid-velocity profile and flow rate in rectangular duct based on laser-diode self-mixing effect was proposed. Based on the self-mixing interference theory and velocity distribution of laminar flow in rectangular duct theory, the feature of frequency spectrum of self-mixing signal of laminar flow in rectangular duct was analyzed. The feature of fluid-velocity profile and flow rate in rectangular duct were obtained. The average relative error of measured fluid-velocity is 2.7%. The relative errors of measured flow rate in rectangular duct are less than 2.0%. Experimental measurements accord with the theory.