Ruo-yu Dong, Bing-yang Cao, He-ming Yun, Bao-ming Chen. Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations[J]. Chinese Journal of Chemical Physics , 2016, 29(6): 754-760. doi: 10.1063/1674-0068/29/cjcp1606129
Citation: Ruo-yu Dong, Bing-yang Cao, He-ming Yun, Bao-ming Chen. Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations[J]. Chinese Journal of Chemical Physics , 2016, 29(6): 754-760. doi: 10.1063/1674-0068/29/cjcp1606129

Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations

doi: 10.1063/1674-0068/29/cjcp1606129
  • Received Date: 2016-06-20
  • Rev Recd Date: 2016-08-11
  • Using nonequilibrium molecular dynamics simulations, we study the non-Newtonian rheological behaviors of a monoatomic fluid governed by the Lennard-Jones potential. Both steady Couette and oscillatory shear flows are investigated. Shear thinning and normal stress effects are observed in the steady Couette flow simulations. The radial distribution function is calculated at different shear rates to exhibit the change of the microscopic structure of molecules due to shear. We observe that for a larger shear rate the repulsion between molecules is more powerful while the attraction is weaker, and the above phenomena can also be confirmed by the analyses of the potential energy. By applying an oscillatory shear to the system, several findings are worth mentioning here:First, the phase difference between the shear stress and shear rate increases with the frequency. Second, the real part of complex viscosity first increases and then decreases while the imaginary part tends to increase monotonically, which results in the increase of the proportion of the imaginary part to the real part with the increasing frequency. Third, the ratio of the elastic modulus to the viscous modulus also increases with the frequency. These phenomena all indicate the appearance of viscoelasticity and the domination of elasticity over viscosity at high oscillation frequency for Lennard-Jones fluids.
  • 加载中
  • [1] H. L. Yang, J. M. Ruan, J. P. Zou, Q. M. Wu, Z. C. Zhou, and Y. Y. Xie, Chin. J. Chem. Phys. 22, 46(2009).
    [2] Q. Wang, H. Z. Li, Y. J. Xie, H. Y. Li, and H. Y. Yang, Chin. J. Chem. Phys. 25, 448(2012).
    [3] V. Citro, F. Giannetti, and J. O. Pralits, Fluid Dyn. Res. 47, 015503(2015).
    [4] D. M. Heyes, J. Non-Newtonian Fluid Mech. 21, 137(1986).
    [5] R. Laghaei, A. E. Nasrabad, and B. C. Eu, J. Chem. Phys. 123, 234507(2005).
    [6] D. J. Evans, Phys. Rev. A 23, 1988(1981).
    [7] R. F. Cracknell, D. Nicholson, and N. Quirke, Phys. Rev. Lett. 74, 2463(1995).
    [8] X. B. Nie, S. Y. Chen, W. N. E, and M. O. Robbins, J. Fluid Mech. 500, 55(2004).
    [9] J. J. Erpenbeck, Phys. Rev. Lett. 52, 1333(1984).
    [10] P. F. Lutsko and J. W. Dufty, Phys. Rev. Lett. 57, 2775(1986).
    [11] D. J. Evans and G. P. Morriss, Phys. Rev. Lett. 56, 2172(1986).
    [12] D. J. Evans, S. T. Cui, H. J. M. Hanley, and G. C. Straty, Phys. Rev. A 46, 6731(1992).
    [13] O. G. Jepps, G. Ayton, and D. J. Evans, Phys. Rev. E 62, 4757(2000).
    [14] L. Lue, O. G. Jepps, J. Delhommelle, and D. J. Evans, Mol. Phys. 100, 2387(2002).
    [15] J. Delhommelle, J. Petravic, and D. J. Evans, J. Chem. Phys. 120, 6117(2004).
    [16] H. H. Gan and B. C. Eu, Phys. Rev. A 45, 3670(1992).
    [17] H. H. Gan and B. C. Eu, Phys. Rev. A 46, 6344(1992).
    [18] Yu. V. Kalyuzhnyi, S. T. Cui, P. T. Cummings, and H. D. Cochran, Phys. Rev. E 60, 1716(1999).
    [19] Yu. V. Kalyuzhnyi, S. T. Cui, and H. D. Cochran, Phys. Rev. E 63, 011209(2000).
    [20] G. S. Grest and K. Kremer, Phys. Rev. A 33, 3628(1986).
    [21] B. Y. Cao, M. Chen, and Z. Y. Guo, Appl. Phys. Lett. 86, 091905(2005).
    [22] B. Y. Cao, M. Chen, and Z. Y. Guo, Phys. Rev. E 74, 066311(2006).
    [23] M. P. Allen and D. J. Tildesley, Computer Simulation of Liquids, New York:Oxford University, (1989).
    [24] H. Eslami and F. Mller-Plathe, J. Phys. Chem. B 114, 387(2010).
    [25] I. Borzsák, P. T. Cummings, and D. J. Evens, Mol. Phys. 100, 2735(2002).
    [26] P. J. Carreau, PhD Thesis, Madison:University of Wisconsin (1968).
    [27] C. M. Tenney and E. J. Maginn, J. Chem. Phys. 132, 014103(2010).
    [28] K. Kawasaki and J. D. Gunton, Phys. Rev. A 8, 2048(1973).
  • 加载中
通讯作者: 陈斌, bchen63@163.com
  • 1. 

    沈阳化工大学材料科学与工程学院 沈阳 110142

  1. 本站搜索
  2. 百度学术搜索
  3. 万方数据库搜索
  4. CNKI搜索

Article Metrics

Article views(837) PDF downloads(607) Cited by()

Proportional views
Related

Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations

doi: 10.1063/1674-0068/29/cjcp1606129

Abstract: Using nonequilibrium molecular dynamics simulations, we study the non-Newtonian rheological behaviors of a monoatomic fluid governed by the Lennard-Jones potential. Both steady Couette and oscillatory shear flows are investigated. Shear thinning and normal stress effects are observed in the steady Couette flow simulations. The radial distribution function is calculated at different shear rates to exhibit the change of the microscopic structure of molecules due to shear. We observe that for a larger shear rate the repulsion between molecules is more powerful while the attraction is weaker, and the above phenomena can also be confirmed by the analyses of the potential energy. By applying an oscillatory shear to the system, several findings are worth mentioning here:First, the phase difference between the shear stress and shear rate increases with the frequency. Second, the real part of complex viscosity first increases and then decreases while the imaginary part tends to increase monotonically, which results in the increase of the proportion of the imaginary part to the real part with the increasing frequency. Third, the ratio of the elastic modulus to the viscous modulus also increases with the frequency. These phenomena all indicate the appearance of viscoelasticity and the domination of elasticity over viscosity at high oscillation frequency for Lennard-Jones fluids.

Ruo-yu Dong, Bing-yang Cao, He-ming Yun, Bao-ming Chen. Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations[J]. Chinese Journal of Chemical Physics , 2016, 29(6): 754-760. doi: 10.1063/1674-0068/29/cjcp1606129
Citation: Ruo-yu Dong, Bing-yang Cao, He-ming Yun, Bao-ming Chen. Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations[J]. Chinese Journal of Chemical Physics , 2016, 29(6): 754-760. doi: 10.1063/1674-0068/29/cjcp1606129
Reference (28)

Catalog

    /

    DownLoad:  Full-Size Img  PowerPoint
    Return
    Return