Design and fabrication of a novel on-chip pressure sensor for microchannels
Design and fabrication of a novel on-chip pressure sensor for microchannels
复制标题
一种新型微通道片上压力传感器的设计和制造
DOI：
10.1039/d2lc00648k
复制
发表时间：
2022
期刊：
影响因子：
6.1
通讯作者：
Li, Yaofa
中科院分区：
文献类型：
--
作者：
Raventhiran, Nishagar;Molla, Razin Sazzad;Nandishwara, Kshithij;Johnson, Erick;Li, Yaofa
从宏观尺度到微/纳米尺度的流体动力学，压力几乎在所有问题中都很重要。尽管在宏观尺度上的压力测量技术已经很发达，但在微观尺度上的压力量化仍然不是微不足道的。本研究报告了一种芯片传感器的设计和制造，该传感器基于一种称为散光粒子跟踪的新技术，可以量化微流控装置中的压力。利用这种技术，可以通过成像嵌入在膜中的颗粒的形状来方便地表征流体流动中的压力变化的薄膜。这种创新的设计仅依赖于微通道背面的反射光，使传感器对感兴趣的流量具有分离性和非侵入性。然后将该传感器用于表征单相流中的压降，精度为~ 70 Pa，并且在传感器，商业压力传感器和数值模拟结果之间取得了良好的一致性。此外，该传感器成功测量了空气-水界面上的毛细管压力，与理论值偏差为7%。据我们所知，这种孔隙尺度的毛细管压力定量是首次使用这种片上压力传感器实现的。本研究提供了一种原位定量局部压力的新方法，从而为重新认识多孔介质中多相流局部压力的孔隙尺度物理打开了大门。
Pressure is important in virtually all problems in fluid dynamics from macro-scale to micro/nano-scale flows. Although technologies are well developed for its measurement at the macroscopic scale, pressure quantification at the microscopic scale is still not trivial. This study reports the design and fabrication of an on-chip sensor that enables quantification of pressure in microfluidic devices based on a novel technique called astigmatic particle tracking. With this technique, thin membranes that sense pressure variations in the fluid flow can be characterized conveniently by imaging the shapes of the particles embedded in the membranes. This innovative design only relies on the reflected light from the back of the microchannel, rendering the sensor to be separate and noninvasive to the flow of interest. This sensor was then applied to characterize the pressure drop in single-phase flows with an accuracy of ∼70 Pa and good agreement was achieved between the sensor, a commercial pressure transducer and numerical simulation results. Additionally, the sensor successfully measured the capillary pressure across an air–water interface with a 7% deviation from the theoretical value. To the best of our knowledge, this pore-scale capillary pressure quantification is achieved for the first time using an on-chip pressure sensor of this kind. This study provides a novel method for in situ quantification of local pressure and thus opens the door to a renewed understanding of pore-scale physics of local pressure in multi-phase flow in porous media.