论文标题
粘弹性流体中的不对称性弱:数值发现和机理探索
Wake asymmetry weakening in viscoelastic fluids: Numerical discovery and mechanism exploration
论文作者
论文摘要
粘弹性削弱了自由域中钝体后面的层流脱落的不对称性。在本研究中,这一发现得到了四个不稳定的粘弹性流动,并具有不对称的流动构型,即,在倾斜的扁平板上流过具有各种发射角的倾斜平板,流过一个旋转的圆形圆柱,流过一个圆形的圆柱上,并在圆形的圆柱体上流过,具有不对称的边界分布,并通过八个均等的圆形cy绕着旋转的圆形cy绕,并且可以通过近距离的圆形cy绕,并且可以通过近距离的圆形旋转(可以平均旋转的圆形)(一个均匀的旋转cy)(可以均匀的圆形cy(a)。模拟与有限扩展的非线性弹性(FENE-P)模型的peterlin近似结合在一起。在高魏森贝格(Weissenberg Number)上,在钝体的额叶区域形成了具有高弹性应力的弧形区域,类似于冲击波。该区域充当固定盾牌,将流动分为不同区域。因此,自由流类似于通过此盾牌而不是原始的钝体。由于此盾牌具有对称特征,因此尾流还原对称性。
Viscoelasticity weakens the asymmetry of laminar shedding flow behind a blunt body in a free domain. In the present study, this finding is confirmed by four unsteady viscoelastic flows with asymmetric flow configuration, i.e., flow over an inclined flat plate with various angles of incidence, flow over a rotating circular cylinder, flow over a circular cylinder with asymmetric slip boundary distribution, and flow over an inclined row of eight equally closely spaced circular cylinders (which can be considered as a single large blunt body) through direct numerical simulation combined with the Peterlin approximation of the finitely extensible nonlinear elastic (FENE-P) model. At high Weissenberg number, an arc shape region with high elastic stress, which is similar to shock wave, forms in the frontal area of the blunt body. This region acts as a stationary shield to separate the flow into different regions. Thus, the free stream resembles to pass this shield instead of the original blunt body. As this shield has symmetric feature, the wake flow restores symmetry.