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arXiv · 2005.05260

Accurate and efficient splitting methods for dissipative particle dynamics

Xiaocheng Shang
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Abstract

We study numerical methods for dissipative particle dynamics (DPD), which is a system of stochastic differential equations and a popular stochastic momentum-conserving thermostat for simulating complex hydrodynamic behavior at mesoscales. We propose a new splitting method that is able to substantially improve the accuracy and efficiency of DPD simulations in a wide range of the friction coefficients, particularly in the extremely large friction limit that corresponds to a fluid-like Schmidt number, a key issue in DPD. Various numerical experiments on both equilibrium and transport properties are performed to demonstrate the superiority of the newly proposed method over popular alternative schemes in the literature.

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Xiaocheng Shang. 2020-05-11. Accurate and efficient splitting methods for dissipative particle dynamics. https://doi.org/10.1137/20m1336230

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