Kim Dongshin, Chesler Naomi C, Beebe David J
Department of Mechanical Engineering, University of Wisconsin, 240 Mechanical Engineering, 1513 University Avenue, Madison, WI 53706, USA.
Lab Chip. 2006 May;6(5):639-44. doi: 10.1039/b517054k. Epub 2006 Mar 20.
The pressure required to drive flow through a microfluidic device is an important characteristic of that device. We present a method to measure the flow rate through microfluidic components and systems, including micropumps and microvalves. The measurement platform is composed of two pressure sensors and a glass tube, which provides series resistance. The principle of the measurement is the fluid dynamical equivalent of Ohm's law, which defines the relationship between current, resistance, and voltage that are analogues to flow rate, hydraulic resistance, and pressure drop, respectively. Once the series resistance is known, it is possible to compute the flow rate through a device based on pressure alone. In addition, the dynamic system characteristics of the device-resistance and capacitance-can be computed. The benefits of this method are its simple configuration, capability of measuring flow rate accurately from the more easily measured pressure, and the ability to predict the dynamic response of microfluidic devices.
驱动流体通过微流控装置所需的压力是该装置的一个重要特性。我们提出了一种测量通过微流控组件和系统（包括微型泵和微型阀）的流速的方法。测量平台由两个压力传感器和一根玻璃管组成，玻璃管提供串联电阻。测量原理是流体动力学中与欧姆定律等效的原理，该原理定义了分别与流速、水力阻力和压降类似的电流、电阻和电压之间的关系。一旦知道了串联电阻，就可以仅基于压力来计算通过装置的流速。此外，还可以计算装置的动态系统特性——电阻和电容。这种方法的优点是其配置简单、能够从更容易测量的压力准确测量流速，以及能够预测微流控装置的动态响应。
