Non-contact optical characterization of negative pressure in hydrogel voids and microchannels

作     者：Shihao Xu Xiaowei Liu Zehua Yu Kang Liu Shihao Xu;Xiaowei Liu;Zehua Yu;Kang Liu

作者机构：MOE Key Laboratory of Hydrodynamic TransientsSchool of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China 

出 版 物：《Frontiers of Optoelectronics》 (光电子前沿（英文版）)

年 卷 期：2022年第15卷第1期

页      面：113-120页

核心收录：

学科分类：081702[工学-化学工艺] 070207[理学-光学] 0808[工学-电气工程] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0702[理学-物理学] 

基　　金：K.Liu acknowledges the National Natural Science Foundation of China(Grant No.51976141) Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2018WNLOKF018). 

主　　题：Hydrogel Negative pressure Non-contact Optical 

摘      要：Negative pressure in water under tension,as a thermodynamic non-equilibrium state,has facilitated the emergence of inno-vative technologies on microfluidics,desalination,and thermal management.However,the lack of a simple and accurate method to measure negative pressure hinders further in-depth understanding of the properties of water in such a state.In this work,we propose a non-contact optical method to quantify the negative pressure in micron-sized water voids of a hydrogel film based on the microscale mechanical deformation of the hydrogel itself.We tested three groups of hydrogel samples with different negative pressure inside,and the obtained results fit well with the theoretical prediction.Furthermore,we demonstrated that this method can characterize the distribution of negative pressure,and can thus provide the possibility of investigation of the flow behavior of water in negative pressure.These results prove this technique to be a promising approach to characterization of water under tension and for investigation of its properties under negative pressure.