轴向旋涡强化矩形喷流掺混的机理研究

本文介绍了在低速射流风洞上开展的二维喷管来流带旋涡的模拟实验。通过流场观察，壁面静压和矩形喷流三维流场的测试。

Study of Mechanism of Axial Vortex Intensifying Rectangular-Jet Mixing

In the paper were carried out experiments on two-dimensional nozzle flow with and without incoming swirling in a low-speed wind tunnel. Incoming velocity profile in boundary layer was measured at the Position where it lays as long as the pipe dimeter upstream of entrance of circular- to- rectangular transition duct. In swirling and nonswirling cases, inlet average velocity is 55m/s. The Reynolds number based on the inlet momentum loss thickness and average velocity is 2520. by the help of seven-hole probe and field visualization, influence of swirling on the mixing property of rectangular jet issuing from two-dimensional nozzle has been carefully studied. Combined with MCC theorm of vortex transport, the research shows that only one vortex, rather than a pair of corotating vortices,exists on the nozzle exit on the condition of incoming flow with swirling. Based on the experimental results and MCC theorm,a new mechamism is deduced about axial vortex intensifying rectangularjet mixing with the surroundings.