Measurements in Vertical Plane Turbulent Plumes
Measurements in Vertical Plane Turbulent Plumes
复制标题
垂直平面湍流羽流的测量
DOI：
--
复制
发表时间：
1989
期刊：
影响因子：
--
通讯作者：
M. Chandrasekhara
中科院分区：
文献类型：
--
作者：
B. Ramaprian;M. Chandrasekhara
在名义上静止的环境中，二维垂直湍流羽流的平均流和湍流测量已经得到。羽流是由含有冷水的水库底部垂直向上注入热水产生的。采用双分量激光多普勒风速仪（LDA）和冷膜电阻温度计测量了羽流中的瞬时速度和温度。目前的平均流测量证实了许多早期的平面羽流测量，但也表明了一些重要的差异。使用双分量LDA可以获得关于湍流强度、湍流通量和平面羽流中湍流结构的其他细节的数据。湍流测量表明，涡动粘度和湍流显着更高的羽相比，等温射流。能量平衡的详细测量表明，浮力产生对这种增加有很大贡献。
Mean-flow and turbulence measurements have been obtained in two-dimensional vertical turbulent plumes in a nominally still ambient. The plumes were generated by injecting hot water vertically upwards from the bottom of a reservior containing cold water. A two-component Laser Doppler Anemometer (LDA) and a “cold-film” resistance thermometer were used to obtain instantaneous velocity and temperature measurements in the plume. The present mean-flow measurements have confirmed many of the earlier measurements on plane plumes, but have also indicated some important differences. The use of the two-component LDA made it possible to obtain data on turbulent intensities, turbulent fluxes and other details of the structure of turbulence in plane plumes. The turbulence measurements have shown that the eddy viscosity and turbulence are significantly higher in the plume compared to an isothermal jet. Detailed measurements of energy balance suggest that buoyant production contributes substantially to this increase.