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Shear viscosity of n-pentane from diffusivity based molecular dynamics methods
Journal of Physics: Conference Series. 2020. Vol. 1556. P. 012048.
Kondratyuk N., Orekhov M.
The molecular dynamics methods for calculation of shear viscosity based on liquid diffusivity are tested against the classical Green–Kubo relation for n-pentane at 330 K and 0.601 g/cm3. The D-based method is shown to be as accurate as calculation of viscosity from the Green–Kubo formalism for pentane liquid. Stokes–Einstein relation is also in agreement with simulation results. However, it has much bigger uncertainty. The results of the simulation are in agreement with experimental data.
Kondratyuk N., Lankin A., Norman G. et al., Journal of Physics: Conference Series 2015 Vol. 653 No. 012107 P. 1-9
Molecular modelling is used to calculate transport properties and to study relaxation of liquid n-triacontane (C30H62). The problem is important in connection with the behavior of liquid isolators in a pre-breakdown state. Two all-atom models and a united-atom model are used. Shear viscosity is calculated using the Green–Kubo formula. The force fields are compared with each other using the ...
Added: April 7, 2017
Kondratyuk N., Pisarev V., Fluid Phase Equilibria 2019 Vol. 498 P. 151-159
Shear viscosity is one of the key subjects of molecular modeling studies since this quality is used in the development of lubricants. In this paper, we use molecular dynamics methods to predict viscosity dependence on pressure up to 1000 MPa for 2,2,4-trimethylhexane. The COMPASS class II force field is used to determine atomic interactions in ...
Added: October 21, 2019
Pisarev V., Mistry S., Fluid Phase Equilibria 2019 Vol. 484 P. 98-105
We present a study of viscosities of methane, n-butane and their mixtures by the non-equilibrium molecular dynamics simulations and derivation of semiempirical volume-based mixing rules. The Batchinski equation $\eta = C / (V - b)$ is used to describe the viscosities of pure components, with parameters fitted to reproduce molecular dynamics results. Cubic root, Arrhenius ...
Added: June 5, 2018
Nikitiuk B., D. I. Salikova, N. D. Kondratyuk et al., Journal of Molecular Liquids 2022 Vol. 368 Article 120714
The scaling between the excess entropy and transport coefficients of liquids is an interesting property found by Rosenfeld in atomistic simulations. Later, Dzugutov proposed to estimate the excess entropy on the basis of the pair entropy. That approach has been shown to work well for atomic liquids and rigid molecules, but there is a problem ...
Added: August 9, 2022
Kondratyuk N., Ryltsev R., Ankudinov V. et al., Journal of Molecular Liquids 2023 Vol. 380 Article 121751
Calculating viscosity in multicompoinent metallic melts is a challenging task for both classical and ab initio molecular dynamics simulations methods. The former may not to provide enough accuracy and the latter is too resources demanding. Machine learning potentials provide optimal balance between accuracy and computational efficiency and so seem very promising to solve this problem. Here we ...
Added: May 16, 2023
Семенякин Н. С., Falkovich G., Physical Review B: Condensed Matter and Materials Physics 2018 Vol. 97 No. 085127 P. 085127-1-085127-5
Strong interaction among charge carriers can make them move like viscous fluid. Here we explore alternating current (AC) effects in viscous electronics. In the Ohmic case, incompressible current distribution in a sample adjusts fast to a time-dependent voltage on the electrodes, while in the viscous case, momentum diffusion makes for retardation and for the possibility ...
Added: April 4, 2018
Kondratyuk N., Pisarev V., Fluid Phase Equilibria 2021 Vol. 544-545 Article 113100
In this paper, we use the molecular dynamics methods to predict the pressure-viscosity dependencies of model lubricant 1,1-diphenylethane up to 800 MPa along three isotherms: 37.8 °C, 60 °C and 98.9 °C. The precise COMPASS class II force field is used to determine atomic interactions in the model. The Green-Kubo method is used to calculate the shear viscosities. The time ...
Added: September 5, 2021
Bakulin I., Kondratyuk N., Lankin A. et al., Journal of Chemical Physics 2021 No. 155 Article 154501
Polyethers are promising compounds for creation of electrochemical energy storage systems. Molecular dynamics method can facilitate the search of such compounds which have the most potential. However, application of this method requires verification of the force fields. We perform molecular dynamics calculations of the physical properties of the aqueous 1,4-dioxane solution (density, enthalpy of mixing, ...
Added: October 15, 2021
Deshchenya V. I., N. D. Kondratyuk, Lankin A. V. et al., Journal of Molecular Liquids 2022 Vol. 367 Article 120456
In this work, we study the applicability of the equilibrium molecular dynamics methods for the prediction of both static and dynamic properties of sucrose aqueous solution for various concentrations and temperatures.
The OPLS-AA force field with 1.14*CM1A charge corrections is used to describe the interactions in the model.
We analyze the prediction power of the model against ...
Added: August 9, 2022
Kondratyuk N., Journal of Chemical Physics 2019 Vol. 151 No. 7 P. 074502-1-074502-8
Decades of molecular simulation history proved that the Green-Kubo method for shear viscosity converges without any problems in atomic and simple molecular liquids, unlike liquids with high values of viscosity. In the case of highly viscous liquids, the time decomposition method was developed in 2015 by Maginn and co-authors [Y. Zhang, A. Otani, and E. ...
Added: October 22, 2019
Kondratyuk N., Pisarev V., Ewen J., Journal of Chemical Physics 2020 Vol. 153 No. 15 P. 154502
Computational predictions of the high-pressure viscosity of hydrocarbon mixtures could help to accelerate the development of fuels and lubricants with improved performance. In this study, we use molecular dynamics simulations to study the viscosity and density of methylcyclohexane, 1-methylnaphthalene, and their binary mixtures at 323 K and pressures of up to 500 MPa. The simulation ...
Added: October 26, 2020