关键词: 带倾角冲击;凹柱面;流场显现;旋流结构

Abstract: Experiments were carried out to investigate the flow structures on concave surface with inclined impingement in a limited narrow space. Smoke wire flow visualization was used to study the characteristics of the flow structures of a round jet inclined impinging on the concave surfaces. Jet Reynolds number,the ratio of jet impingement distance to the diameter of the jet hole,inclined jet angle and the relative curvature were changed to study the rules of flow structures varying with these parameters. The experimental results show that the central angle of the impingement fluid separating from target surface becomes larger as increasing Reynolds number and flow separation is delayed. Because of the influence of inclined jet,it was easier to generate swirl vortex structures at relatively smaller angle side of inclined impingement than the relatively larger central angle side,and the separating at relatively smaller angle side was brought forward. All the results indicate that the vortex structures were affected by all above parameters at the same time,and the rules of vortex structures varying with these parameters are strongly correlated.

Key words: Inclined impingement;Concave surface;Flow visualization;Vortex structures