A modular particle–continuum numerical method for hypersonic non-equilibrium gas flows

Algorithm Refinement for Fluctuating Hydrodynamics

“…Stochastic hybrid methods were developed in [10] (mass diffusion), [11] (the "train model" for momentum diffusion), and [12] (Burgers' equation). Other recent work on coupling particle and continuum methods includes [13] (DSMC and Navier-Stokes, for aerospace applications), [14] (molecular dynamics and isothermal fluctuating hydrodynamics, for polymer simulations), and [15] (an adaptive refinement approach based on a direct numerical solution of the Boltzmann transport equation and kinetic continuum schemes).…”

“…Given their complexity, the implementations of hybrid codes benefit greatly from modularization (e.g., see [13]). Another fundamental tenant of the AMAR approach to particle-continuum hybridization is that the coupling of the two algorithms is completely encapsulated in several "hand-shaking" routines.…”

A gas kinetic scheme for hybrid simulation of partially rarefied flows

“…In the §ux-based coupling, instead, at a designed interface, the numerical §uxes for one solver are obtained from the other as shown in Fig. 3b, while for hybrid NS-DSMC simulations, the choice of a state-based coupling is the preferable one due to the lower scattering error that it involves [12]. In the current deterministic DVM kinetic solver, the statistical scatter is absent, creating more §exibility in the used coupling technique.…”

“…In the current deterministic DVM kinetic solver, the statistical scatter is absent, creating more §exibility in the used coupling technique. In the literature, Figure 3 Coupling techniques, adapted from [12]: (a) state-based coupling; and (b) §ux-based coupling the domain decomposition is generally done during the simulation on the basis of a continuum breakdown parameter, for example, as done by other researchers in [12,29]. At the moment, this feature is still under development in M C and the DVM domain has to be de¦ned by the user in an input ¦le.…”

“…A hybrid technique couples two simulation methods by means of information exchange between the parts of the §ow domain. In recent works, this has been achieved using an overlap region where §ow state variables or numerical §uxes are exchanged between the two models [12] or employing a bu¨er region where the two models are blended at equation level [13]. Recent works on these methods focused on rare¦ed high-Mach §ow can be found in [14 16].…”