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20世纪60年代后,先后从流动显示发现了快慢斑、猝发、上升流、下扫流和多种涡结构等湍流边界层的拟序结构．它们对湍流边界层的摩阻、传热传质和湍动能的产生等特性有重要影响．涡结构是上述拟序结构的核心,它影响其它拟序结构的发展和演变．发卡涡通常被认为是基本涡结构．发卡涡等涡结构的再生,是湍流边界层拟序结构能够自持续的必要的因素．壁面低速流上升产生猝发,是湍流边界层湍能的主要来源;条件采样是测量猝发频率和其它拟序结构出现频率的重要手段．流动显示对湍流边界层拟序结构作了大量定性观察,有许多减阻和增加传热率等应用性研究在此基础上发展起来．80年代后,出现了测量湍流边界层的瞬时流速矢量场的多热线法和PIV技术,三维PIV技术可望将来为湍流边界层的实验研究带来重大进展．本文评述了流动显示法、多热线法和PIV技术的优点和不足之处,以及它们在对湍流边界层拟序结构的研究中的贡献．
After the 1960s, the sequence structures of turbulent boundary layers such as fast and slow spots, bursts, ascending flow, down-wakes and various vortices were discovered from the flow and deposition. They have important influence on the frictional resistance, heat and mass transfer and turbulent kinetic energy of the turbulent boundary layer. Vortex structure is the core of the proposed structure, which affects the development and evolution of other structures. Card vortexes are often considered as basic vortex structures. The regeneration of the vortex structure such as the card-issuing vortex is a necessary factor for the self-sustaining structure of the turbulent boundary layer. The sudden rise of the wall velocity at low velocity produces a burst, which is the main source of turbulent boundary layer turbulence. Condition sampling is an important measure to measure the frequency of the burst and the frequencies of other ordered structures. The flow shows a large number of qualitative observations of the ordered structure of the turbulent boundary layer, and many applied studies such as drag reduction and increase of heat transfer rate have been developed on this basis. Since the 1980s, a multi-hotline method and a PIV technique for measuring the instantaneous velocity vector field of a turbulent boundary layer have appeared. The three-dimensional PIV technique is expected to make major progress in the experimental study of the turbulent boundary layer in the future. This paper reviews the advantages and disadvantages of the flow display method, the hot-wire method and the PIV technique, and their contributions to the study of the ordered structure of turbulent boundary layers.