Author(s): Xuyue Hu; Huaqiang Ren; Xiaoxiong Shen
Linked Author(s):
Keywords: Non-submerged live vegetation; Reynolds stress; Velocity distribution equation; Binormal distribution; Uncertainty
Abstract: An experiment with non-submerged live vegetation was performed in a flume, and statistical analysis of velocity data measured along vertical lines was conducted with the time average method. Based on the theory that the energy of flows diffuses toward the nearest boundary, an equation for flow velocity distribution in non-submerged vegetation was analyzed and derived. The velocity in the main flow direction was calculated by using the derived equation and the classical logarithmic equation with wave function, respectively; the calculated values and the measured value were compared and analyzed; the result shows that the actual data can be better described when the derived equation is used. Meanwhile, velocity distribution was adjusted according to the law that the frequency of occurrence of velocity is in binormal distribution, and the representative vertical velocity distribution in the cross-sections was obtained. The conclusion indicates that live vegetation can cause uncertainty of Reynolds stress and vertical velocity distribution of flows.
Year: 2013