Gas flow behavior in porous media with micro- and nanoscale pores has always been attracted great attention. Gas transport mechanism in such pores is a complex problem, which includes continuous flow, slip flow and transition flow. In this study, the microtubes of quartz microcapillary and nanopores alumina membrane were used, and the gas flow measurements through the microtubes and nanopores with the diameters ranging from 6.42 μm to 12.5 nm were conducted. The experimental results show that the gas flow characteristics are in rough agreement with the Hagen-Poiseuille (H-P) equation in microscale. However, the flux of gas flow through the nanopores is larger than the H-P equation by more than an order of magnitude, and thus the H-P equation considerably underestimates gas flux. The Knudsen diffusion and slip flow coexist in the nanoscale pores and their contributions to the gas flux increase as the diameter decreases. The slip flow increases with the decrease in diameter, and the slip length decreases with the increase in driving pressure. Furthermore, the experimental gas flow resistance is less than the theoretical value in the nanopores and the flow resistance decreases along with the decrease in diameter, which explains the phenomenon of flux increase and the occurrence of a considerable slip length in nanoscale. These results can provide insights into a better understanding of gas flow in micro- and nanoscale pores and enable us to exactly predict and actively control gas slip.
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http://dx.doi.org/10.1038/s41598-019-46430-2 | DOI Listing |
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Department of Biochemistry and Molecular Biology B and Immunology, University of Murcia, Murcia, Spain.
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January 2025
Department of Applied Chemistry, Faculty of Chemistry, Razi University, 67144-14971, Kermanshah, Iran.
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Institute of Agrochemistry and Food Technology (IATA, CSIC), Spain.
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Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, China; Department of Chemical Engineering, Tsinghua University, Beijing, China; Key Lab for Industrial Biocatalysis, Ministry of Education, Tsinghua University, Beijing, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing, China; School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, Shihezi University, Shihezi, Xinjiang, China. Electronic address:
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