Hydrodynamics of discrete-particle models of spherical colloids: A multiparticle collision dynamics simulation study

Abstract

We investigate the hydrodynamic properties of a spherical colloid model, which is composed of a shell of point particles by hybrid mesoscale simulations, which combine molecular dynamics simulations for the sphere with the multiparticle collision dynamics approach for the fluid. Results are presented for the center-of-mass and angular velocity correlation functions. The simulation results are compared with theoretical results for a rigid colloid obtained as a solution of the Stokes equation with no-slip boundary conditions. Similarly, analytical results of a point-particle model are presented, which account for the finite size of the simulated system. The simulation results agree well with both approaches on appropriative time scales; specifically, the long-time correlations are quantitatively reproduced. Moreover, a procedure is proposed to obtain the infinite-system-size diffusion coefficient based on a combination of simulation results and analytical predictions. In addition, we present the velocity field in the vicinity of the colloid and demonstrate its close agreement with the theoretical prediction. Our studies show that a point-particle model of a sphere is very well suited to describe the hydrodynamic properties of spherical colloids, with a significantly reduced numerical effort.

Hydrodynamic correlations in shear flow: Multiparticle-collision-dynamics simulation study

“…In particular, the hydrodynamic correlations of the MPC fluid have been determined and it has been shown that they agree with the solutions of the fluctuating Landau-Lifshitz NavierStokes equations [25]. Moreover, the hydrodynamic correlations of embedded colloids [26][27][28][29][30][31] and polymers [32] have been calculated. Even more, MPC simulations have been successfully applied to verify the fluctuation relation for entropy production in shear flows [11].…”

Dramatic influence of patchy attractions on short-time protein diffusion under crowded conditions

“…A protein is represented by a spherical shell composed of point particles, which are connected by suitable elastic bonds to maintain its shape ( 35 ). The colloids are embedded in the MPC fluid to account for hydrodynamic interactions.…”

“…The colloids are embedded in the MPC fluid to account for hydrodynamic interactions. Calculations of colloid velocity correlation functions provide the correct hydrodynamic behavior on relevant length and time scales ( 35 ). Interactions between spherically symmetric colloids are described by the short-range attractive potential of Eq.…”

Bulk viscosity of multiparticle collision dynamics fluids

“…However, angular-m om entumconserving extensions have been introduced for both the stochastic rotation version of M PC (M P C -S R D + a) and the ' m.theers@fz-juelich.de T.winkler@fz-juelich.de PACS number(s): 47.11 ,-j , 02.70.Ns, 6 6 .20.-d A ndersen variant (M PC -A T + a) [17,18]. The M PC m ethod has successfully been applied to a broad range o f soft m atter system s ranging from equilibrium colloid [6,8,9,[19][20][21][22][23][24][25][26][27] and polym er [8,9,[28][29][30] solutions and, m ore importantly, nonequilibrium system s such as colloids [16,[31][32][33][34][35], poly mers [29,[36][37][38][39][40][41][42][43][44][45], vesicles [46], and cells [47,48] in flow fields, colloids in viscoelastic fluids [49][50][51], to selfpropelled spheres [52][53][54], rods …”