Reynolds Number Effects on Boundary Layer Turbulent Transport

本项目的目的是确定雷诺数在湍流边界层结构中的作用。输运方程中重要项的测量将在表层湍流和环境科学（SLTEST）设备上进行，雷诺数范围为103至106。SLTEST设施利用了犹他州西部大盐湖沙漠上空的大气表面层。探头将提供描述轴向应力和浓度方差传输的方程中单个项的空间和时间分辨测量。还将测量速度-涡度的相关性。由两个光电离传感器和四条热线组成的标量输运探针将用于获取与标量方差输运方程相关的数据。SLTEST设备将产生低速、大尺度边界层。这些设施的重要性在于它们允许高度分辨的空间和时间测量。为了工程应用的目的，如空气动力学车辆减阻，对传输机制的基本理解可能在设计中有用。

The objective of this project is to determine the role of Reynolds number in the structure of the turbulent boundary layer. Measurements of important terms in transport equations will be made at the Surface Layer Turbulence and Environmental Science (SLTEST) facility at Reynolds numbers ranging from 103 to 106. The SLTEST facility makes use of the atmospheric surface layer that flows over the Great Salt Lake Desert in western Utah. Probes will provide spatially and temporally resolved measurements of the individual terms in the equations describing the transport of axial stress and concentration variance. Measurements will also be made of the velocity-vorticity correlations. A scalar transport probe, consisting of two photo-ionization sensors and four hot-wires, will be used to obtain data relating to the scalar variance transport equation. The SLTEST facility will produce low-speed, large length-scale boundary layers. The importance of these facilities is that they allow highly resolved spatial and temporal measurements. For the purposes of engineering applications such as aerodynamic vehicle drag reduction, fundamental understanding of transport mechanisms could be useful in design.