AI 中文总结
本研究通过直接数值模拟发现，对于Oldroyd-B和FENE-P两种本构模型，随德博拉数增大，弹性湍流会达到终极状态，此时流体耗散等体相量与聚合物松弛时间无关。
AI 中文摘要
多年来，牛顿流体中惯性湍流在粘性消失时的渐近性质受到了大量关注，但对于弹性湍流——粘弹性流体表现出的一种独特的时空混沌状态，人们知之甚少。本研究通过对三维周期性盒子内的湍流进行直接数值模拟，发现对于Oldroyd-B和FENE-P两种不同的本构模型，当聚合物松弛时间（即德博拉数）增大时，弹性湍流会达到一种终极状态。在该极限状态下，流体耗散、聚合物能量传递以及弹性应力等各种体相量均与聚合物松弛时间尺度无关，不过微观结构的变形尺度仍会因模型不同而存在明显差异。
英文摘要
The asymptotic properties, with vanishing viscosity, of inertial turbulence in Newtonian fluids have been of intense scrutiny over the years. Much less is known about elastic turbulence - a distinct spatio-temporally chaotic state exhibited by viscoelastic fluids. In this work, using direct numerical simulations of turbulence in a triperiodic box, we show that elastic turbulence achieves an ultimate state with increasing polymer relaxation time, i.e., the Deborah number, for two different constitutive models (Oldroyd-B and FENE-P). In the limiting state, various bulk quantities - the fluid dissipation, the polymeric energy transfer, as well as the elastic stresses - are shown to become independent of the polymer relaxation time scale, notwithstanding the microstructure deformation scales distinctly depending on the model.
