We present techniques to measure fluid flow rates in single- and multi-phase fluid flows by detecting the motion of injected tracers. Our methods exploit acoustic impedance differences between liquids and gases to allow one to sense the presence of micron-sized gas bubbles in a liquid when it is irradiated with ultrasonic energy. By cross-correlating signals at multiple locations along the path of flow, the velocity of the moving fluid can be accurately estimated. We report experimental results in single- and two-phase fluid flows and describe the methodologies used in each case that are necessary to enable accurate measurements. In cases of single- and two- phase flows, respectively, flow rates can be measured to less than 5% and less than 10%–15% of known flow rates. While our experiments leveraged differences in acoustic properties, the methods may be generalized to other means of measurement.

我们提出了通过检测注入示踪剂的运动来测量单相和多相流体流中流体流速的技术。我们的方法利用液体和气体之间的声阻抗差异，使人们能够在用超声波能量照射液体时感知液体中微米级气泡的存在。通过对沿流动路径的多个位置的信号进行互相关，可以准确估计移动流体的速度。我们报告了单相和两相流体流动的实验结果，并描述了在每种情况下使用的方法，这些方法是实现准确测量所必需的。分别在单相和两相流的情况下，流速可以测量到小于已知流速的 5% 和小于 10%–15%。虽然我们的实验利用了声学特性的差异，