风洞整流孔板流动CFD边界条件建模

A boundary model for the computation of the flow across the screen in the wind tunnel

风洞设计中,普遍采用孔板、金属网等构件进行整流。但孔板流动很复杂,一般只能依据经验并开展引导性试验进行设计与优化。随着CFD技术的发展,风洞设计自然也希望能利用CFD技术,但孔板等复杂构件的流动对此造成很大挑战。通过忽略孔板大量微小开孔中的流动细节,仅考虑多孔板的宏观效应,建立了一种反映多孔板宏观效应的CFD计算边界条件模型,极大缩减了计算规模,并结合2m×2m超声速风洞引导性试验进行了初步计算应用,取得了一定的效果。

Screens and metal grids are commonly used to adjust the flow in the design of wind tunnels. While the flow across the screen is rather complicated, the design and optimization of the screen are generally conducted by experiences and investigating experiments. With the development of CFD techniques, the screen flow could be solved although it still remains a big challenge. A computational boundary model consid- ering the macro-effects of the screen was built up, which ignored the flow details across the numerous small holes of the screen. By this way, the computational grids and times could be dramatically reduced. The mod- el was preliminarily tested in the computation and combined with the investigating experiments conducted for the 2m×2m supersonic wind tunnel design, and its effect is noticeable.