A three - dimensional - acoustic doppler velocimeter is used to measure the velocity components of the flow field in all three coordinate directions for different discharge and measurement site . the influence of measurement site and the depth / vegetation height ratio on the measured velocity profile and turbulence intensity and the renolds stress is analyzed . the characteristics of the measured velocity distributions and the results of the previous investigators are used to select an analytical expression for the shape of the velocity profile 利用三维超声波多普勒流速仪( adv )量测不同位置、不同流量下的瞬时流场。分析了测点位置和水深与植被高度比对时均流速分布的影响。本文还给出了种树段紊动强度及雷诺应力的垂线分布。
Laser doppler velocimeter ( ldv ) is a precise instrument based on the theory of laser doppler effect with no - touch measurement capability , quick responsibility , high precision , wide measurement range , multiple dimension measurement and direction judgement ability . ldv is applied extensively in the field of science research & education and industrial measurement . in this thesis , we researched on the high - precise signal processing in ldv 激光多普勒测速仪( ldv )是根据激光多普勒效应研制而成的一种精密测速仪器,具有非接触测量、动态响应快、分析精度高、测量范围宽、可测多维速度和判别速度方向等优点,被广泛应用于科研教育领域和工业测量领域。
3 . a three - dimensional - acoustic doppler velocimeter has been used to measure the velocity and turbulence in a compound channel with vegetated and unvegetated flood - plains . particulary in the interface region between main channel and floodplain . the distribution in three coordinate directions of velocity and turbulence intensities and the renolds stresses are presented . the momentum transfer at the main channel flood - plain interface can be described as an apparent shear stress which can be quantified as a function of the local turbulence at the interface 采用adv对滩地种树前后滩槽交界区域的流速场进行了量测。分析了滩槽交界区域的垂线流速、紊动强度和雷诺应力的变化。将滩槽交界的动量传递描述为一表观应力，这个表观应力可以看作是交界面处的脉动函数并将其定量化。
