Multi-scale computational modelling of flow and heat transfer

Purpose - The purpose of this paper is to present different approaches for applying macroscopic boundary conditions in hybrid multiscale modelling. Design/methodology/approach - Molecular dynamics (MD) was employed for the microscopic simulations. The continuum boundary conditions were applied either through rescaling of atomistic velocities or resampling based on velocity distribution functions. Findings - The methods have been tested for various fluid flows with heat transfer scenarios. The selection of the most suitable method is not a trivial task and depends on a number of factors such as accuracy requirements and availability of computational resource. Originality/value - The applicability of the methods has been assessed for liquid and gas flows. Specific parameters that affect their accuracy and efficiency have been identified. The effects of these parameters on the accuracy and efficiency of the simulations are investigated. The study provides knowledge regarding the development and application of boundary conditions in multiscale computational frameworks.