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[1] Li Jiapeng, Bi Kedong, Chen Yunfei, Chen Min, et al. Molecular dynamics study of viscosity of aqueous NaCl solutionconfined in nanoscale channels [J]. Journal of Southeast University (English Edition), 2011, 27 (3): 257-260. [doi:10.3969/j.issn.1003-7985.2011.03.006]
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Molecular dynamics study of viscosity of aqueous NaCl solutionconfined in nanoscale channels()
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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:
27
Issue:
2011 3
Page:
257-260
Research Field:
Mathematics, Physics, Mechanics
Publishing date:
2011-09-30

Info

Title:
Molecular dynamics study of viscosity of aqueous NaCl solutionconfined in nanoscale channels
Author(s):
Li Jiapeng1;  Bi Kedong1;  Chen Yunfei1;  2;  Chen Min1;  Wang Zhu1(1 Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments;  Southeast University;  Nanjing 211189;  China)
2 Key Laboratory of MEMS of Educational Ministry, Southeast University, Nanjing 210096, China
Keywords:
nanochannel;  molecular dynamics simulation;  vibrating silicon atom;  shear rate;  viscosity
PACS:
O351.2
DOI:
10.3969/j.issn.1003-7985.2011.03.006
Abstract:
A physical model of bulk-nanochannel-bulk with buffer baths is built up using nonequilibrium molecular dynamics(MD)simulation to study the effects of vibrating silicon atoms on the viscosity of aqueous NaCl solutions confined in the nanochannel. The simulation is performed under different moving speeds of the upper wall, different heights and different surface charge densities in the nanochannel. The simulation results indicate that with the increase in the surface charge density and the decrease in the nanochannel height and the shear rate, the vibration effect of silicon atoms on the shear viscosity of the confined fluid in the nanochannel cannot be ignored. Compared with still silicon atoms, the vibrating silicon atoms result in the decrease in the viscosity when the height of the nanochannel is less than 0.8 nm and the shear rate is less than 1.0×1011 s-1, and the effect of the vibrating silicon atoms on the shear viscosity is significant when the shear rate is small. This is due to the fact that the vibrating silicon atoms weaken the interactions between the counter-ions(Na+)and the charged surface.

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Memo

Memo:
Biographies: Li Jiapeng(1981—), male, graduate; Chen Yunfei(corresponding author), male, doctor, professor, yunfeichen@seu.edu.cn.
Foundation items: The National Basic Research Program of China(973 Program)(No.2006CB300404), the National Natural Science Foundation of China(No.50875047, 50676019), the Natural Science Foundation of Jiangsu Province(No.BK2006510, BK2008201).
Citation: Li Jiapeng, Bi Kedong, Chen Yunfei, et al. Molecular dynamics study of viscosity of aqueous NaCl solution confined in nanoscale channels. [J].Journal of Southeast University(English Edition), 2011, 27(3):257-260.[doi:10.3969/j.issn.1003-7985.2011.03.006]
Last Update: 2011-09-20