求解释：昆塔条件

cyliqh

我不是学流体的，但是最近有很涉及空气动力学的内容。有很多不懂得问题，想请各位替我解释一下。

昆塔条件（Kutta condition）

文献中是这样写
Under completely inviscid conditions, one would expect the
fluid to deflect only minimally by the presence of an airfoil,
thereby generating a flow field around the wing similar to the
one described in Fig.·2A. Under such conditions, the rear
stagnation point (where velocity is zero) would be present not
at the tip of the trailing edge but on the upper surface of the
wing. However, to maintain this flow profile, the fluid must
turn sharply around the trailing edge causing a singularity or
‘kink’ in the flow at the trailing edge. Such a flow profile
necessitates a high gradient in velocity at the trailing edge,
thereby causing high viscous forces due to shear. The viscous
forces in turn will eventually eradicate this singularity. Thus,
the presence of even the slightest viscosity in the fluid
functions to smooth out sharp gradients in flow. This
phenomenon may be incorporated into an otherwise inviscid
formulation by adding a circulatory component to the flow field
(Fig.·2B). At a unique value of the additional circulation, the
stagnation point is stationed exactly at the trailing edge. When
this condition is met, the fluid stream over the plate meets the
fluid stream under the plate smoothly and tangentially at the
trailing edge (Fig.·2C). This phenomenon is called the ‘Kutta
condition’, which ensures that the slopes of the fluid streams
above and below the wing surface are equal, and thus the
vorticity (i.e. curl of the velocity) at the trailing edge is zero.
In addition, when satisfied, the Kutta condition ensures that the
inclined plate imparts a downward momentum to the fluid.
This, in essence, is the classic Kutta–Jukowski theory of thin
airfoils (Kuethe and Chow, 1998).】

图见附件！

求解释！谢谢！！！~~

onesupeng

第一次见人叫昆塔

所谓库塔条件就是认为尖缘点处速度有限

另：看不懂英文多看中文，熟悉概念

uesoft

原帖由 onesupeng 于 2010-11-11 19:19 发表
第一次见人叫昆塔
所谓库塔条件就是认为尖缘点处速度有限
另：看不懂英文多看中文，熟悉概念

说明流体作用很大，很普及了