当前位置: X-MOL 学术J. Non-Newtonian Fluid Mech. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
An Oldroyd-B solver for vanishingly small values of the viscosity ratio: Application to unsteady free surface flows
Journal of Non-Newtonian Fluid Mechanics ( IF 3.1 ) Pub Date : 2020-06-28 , DOI: 10.1016/j.jnnfm.2020.104338
C. Viezel , M.F. Tomé , F.T. Pinho , S. McKee

This work is concerned with time-dependent axisymmetric free surface flows of Oldroyd-B fluids for any value of

, the ratio of solvent to total viscosities. The Oldroyd-B constitutive equation is dealt with by employing a novel technique to calculate the conformation tensor while an EVSS transformation allows the solution of the momentum equations coupled with the free surface stress conditions: this avoids numerical instabilities that can arise when using small values of
. The convergence of this new methodology is verified on pipe flow and also by comparing results from the literature for the time-dependent impacting drop problem. This approach is then used to predict the time-dependent free surface flow after a viscoelastic drop impacts a solid surface for
values in the range [0, 1]. The impacting drop problem is investigated for polymer solutions containing a small solvent contribution (
) or without any solvent viscosity (
). In addition, a study of the bouncing drop problem for different values of
, Weissenberg and Reynolds numbers is undertaken.



中文翻译:

粘度比值逐渐减小的Oldroyd-B求解器:适用于不稳定的自由表面流

这项工作是关于Oldroyd-B流体随时间变化的轴对称自由表面流的任何值。

,溶剂与总粘度之比。Oldroyd-B本构方程是通过采用一种新颖的技术来计算构象张量来处理的,而EVSS变换则允许对动量方程的解和自由表面应力条件进行求解:这样可以避免在使用较小值的情况下可能出现的数值不稳定性。
。这种新方法的收敛性已经在管道流量上进行了验证,并且还通过比较了文献中随时间变化的影响跌落问题的结果进行了验证。然后,该方法用于预测粘弹性液滴撞击固体表面后随时间变化的自由表面流动。
值在[0,1]范围内。对于溶剂贡献少的聚合物溶液,研究了冲击滴问题(
)或没有任何溶剂粘度(
)。另外,对于不同值的跳动跌落问题的研究
,Weissenberg和Reynolds数被采用。

更新日期:2020-06-28
down
wechat
bug