论文标题
使用时间依赖性的自我相似性，围绕加速平板的分离流的理论模型
A theoretical model for the separated flow around an accelerating flat plate using time-dependent self similarity
论文作者
论文摘要
我们提出了一个适合于无粘性流体加速平板机翼的初始运动（2-3个和弦）的模型。分离的流量结构以常规方式表示为涡旋表，并且开发了适用于板的前导和后尾边缘的相似性扩展。维持涡流纸的拓扑特征，而不是诉诸于点涡流离散。除此之外，与以前的研究相比，我们的方法还有两个理论上的新颖性。首先，将膨胀应用于附着的外流，而不是涡流纸循环和位置。这允许平行于板的自由流动流的扫描组件的不对称效应与单数阶流相同的管理方程式内置。其次，我们开发了一个与时间相关的自我相似性程序，该过程允许建模流量结构。这是通过相似性变量的隐式时间变化来实现的。作为集体结果，板上预测的涡流动力学和力与Navier-Stokes模拟相比。最后，该模型用于提供一些有关前缘分离流的新直觉。
We present a model appropriate to the initial motion (2-3 chords of travel) of a flat-plate airfoil accelerating in an inviscid fluid. The separated flow structures are represented as vortex sheets in the conventional manner and similarity expansions locally applicable to the leading and trailing edges of the plate are developed. The topological character of vortex sheets is maintained rather than resorting to point vortex discretizations. Beyond this, there are two theoretical novelties to our approach as compared to previous studies. First, an expansion is applied to the attached outer flow rather than the vortex sheet circulations and positions. This allows the asymmetric effect of the sweeping component of the free-stream flow parallel to the plate to be built-in to the same governing equation as the singular-order flow. Second, we develop a time-dependent self similarity procedure that allows the modeling of more complex evolution of the flow structures. This is accomplished through an implicit time variation of the similarity variables. As a collective result, the predicted vortex dynamics and forces on the plate compare favorably to Navier-Stokes simulations. Lastly, the model is utilized to provide some new intuition about the separated flow at the leading edge.
