雷诺数对半封闭紊流冲击射流流场影响的实验研究

通过采用热线风速仪给出了在半封闭、入射高度为2倍喷管直径时三种不同的雷诺数下紊流中冲击射流流场的详细的测量结果，并与文献结果作了比较。表明在上述条件下，雷诺数对主流速度的影响很小，对紊功能的影响也不太大，且主要集中在冲击区的近壁面部分。所得结果为数值计算冲击射流提供了实验数据。

Experimental Study of Reynolds Number Effect on Turbulent Impinging Jet Flow

Adopting the IFA-300 hot wire/film anemometer,the detailed measurement results about the effect of out-flow Reynolds number on the semi-confined turbulent impinging jet flow field are provided. The Reynolds numbers considered are 23 000,35 000 and 70 000, respectively, and the impinging height from the jet exit to impingement wall is set 2D (D is the diameter of the pipe). The results of the Re=23 000 are compared with those of the LDV in this paper. It is shown that the “damping” effect mainly exists in the zone of 0. 5D from the impingement wall, and there are favored as well as adverse pressure gradient in the radial direction. Under above mentioned condition the Reynolds number has very little effect on the main stream velocity, while a little effect on the turbulent kinetic energy, which is mainly in the impinging area near the impingement wall. The data are used as a database in the future numerical simulation of the turbulent impinging jet.