Brownian dynamics simulation of branched polymer eztensional rheological properties
Finitely extensible nonlinear elastic (FENE) bead-spring chain model for dilute solutions of branched polymer molecules in a Newtonian solvent is employed to describe the bead-bead interaction within a molecule. Brownian dynamics simulation is used to capture the steady state and transient rheological behavior of branched polymer in extensional flow. The simulations include examination of the effects of viscosity depending on length of the branching chain, spring parameter, and extensional rate. The flow situations and the rheological material functions are investigated. A large difference on the rheological response to different finite extensibility length is observed in this study. The semi-implicit predictor-corrector method is employed to solve governing equations while Newtonian iteration method is used to solve nonlinear equations.In the algorithm 12, given the solution Oni at time t=mδt, the solution On i+1 an the next time step t=(m+1)δt,is obtained as follows:O*i=Omi+(K·Omi)+1/4(Fs,m i-1)-2Fs,m i+Fs,m i+1)t+√dt/2(Ωi+1-Ωi),Oi+1/2(δt)Fsi=Omi+1/2(K·Omi+K·O*i)+1/4(Fs,m i*1+Fs,m i+1)δt+√dt/2(Ωi+1-Ωi), (2)Om+1 i+1/2(δt)Fs,m+1 i=Om i+1/2(K·Om i+K·Om i)+1/4(Fs,m i-1)+Fs,m i+1δt+√dt/2(Ωi+1-Ωi)Where Fs,m i is the spring force for the ith segment at time t=mδt(m=1,2,3…)The Eqs.(1), (2) result in a cubic equation, which have a unique root for |Oi|that liesbetween 0 and√b.Once the connector vectors of all the beads have been determined, then substituting Om+1 i into Eq. (8), the polymer contribution to the total stress,i p,can be obtained.
Z.Y.Min W.Cao C.Y.Shen
Luoyang Institute of Science and technology,Luoyang,471023 China National Engineering Research Center On Advanced Polymer Process Technology,Zhengzhou University,Zhe
国际会议
南京
英文
1-2
2009-10-18（万方平台首次上网日期，不代表论文的发表时间）