Analytical and Computational Studies of Correlations of Hydrodynamic Fluctuations in Shear Flow

Journal Article · Mon Jan 01 00:00:00 EST 2018 · Communications in Computational Physics

DOI:https://doi.org/10.4208/cicp.oa-2017-0051· OSTI ID:1565711

Bian, Xin ^[1]; Deng, Mingge ^[1]; Karniadakis, George Em ^[1]

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1. Brown Univ., Providence, RI (United States). Dept. of Applied Mathematics

Correlations of hydrodynamic fluctuations in shear flow analytically and also by dissipative particle dynamics (DPD) simulations are studied. The hydrodynamic equations are linearized around the macroscopic velocity field and then solved by a perturbation method in Fourier-transformed space. The autocorrelation functions (ACFs) from the analytical method are compared with results obtained from DPD simulations under the same shear-flow conditions. Up to a moderate shear rate, various ACFs from the two approaches agree with each other well. At large shear rates, discrepancies between the two methods are observed, hence revealing strong additional coupling between different fluctuating variables, which is not considered in the analytical approach. In addition, the results at low and moderate shear rates can serve as benchmarks for developing multiscale algorithms for coupling of heterogeneous solvers, such as a hybrid simulation of molecular dynamics and fluctuating hydrodynamics solver, where thermal fluctuations are indispensable.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF); Argonne National Lab. (ANL), Argonne, IL (United States); UT-Battelle LLC/ORNL, Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC02-06CH11357; AC05-00OR22725
• OSTI ID: 1565711
• Journal Information: Communications in Computational Physics, Vol. 23, Issue 1; ISSN 1815-2406
• Publisher: Global Science Press
• Country of Publication: United States
• Language: English

Related Subjects

Physics