本文通过二维激光测速试验分析了孔板流场特性，并深入研究了孔板内缘型式对流场影响规律，采用圆形管道和模拟孔板断面的矩形管道两种模型试验对比分析，研究了孔板环内分离流发展过程与孔板内缘型式的关系，从而揭示了内缘型式对消能系数影响的内部机理。 In this paper, the flow field characteristics of the orifice were analyzed by two-dimensional laser velocity test. The influence of the inner edge pattern of the orifice on the flow field was studied in detail. Two models of circular pipe and rectangular pipe with simulated orifice section were contrasted and analyzed. The relationship between the development of the separated flow in the orifice ring and the inner edge of the orifice was revealed, revealing the internal mechanism of the influence of the inner edge type on the energy dissipation coefficient.