摘要
对四种壁画型流体剪切力测量差压计Ｓｔａｎｔｏｎ管，Ｋ型管，穴型管，及微孔表面差压管在湍流边界层条件下进行试验并对其结构特点进行比较后表明，这四种差压计具有相同的特征，所测量的区差均为流量动量变化所致，其流体剪切力可以表示为τ＝Ｃ△Ｐ￣ｎ，为避免对标定数据过于繁复的多段拟会，并使差压计能在较大测量范围内保持拟合公式的精度，各类差压管在与固体壁画铅垂方向上的尺度值应尽量低，微孔表面差压管结构复杂，灵敏度低，但它具有线性特性。
Four types of wall bounded shear stress measuring devices,Stanton tube,K-tube, Caved-tube and Porous Surface tube with different designs were investigated in a pipe within a wide measurement range.The experimental results show that all these tabes have identical feature and the shear stress can be described as a function of differential. pressure τ=C△Pn.The formula has the same form as derived from the physical model presented in this paper.Compared with K-tube and Caved-tube and Porous Surface tube the Stanton tube is more practical. The best way to improye the tubes is to decrease the value of their characteristic height H, i. e. the orifice height of Stanton tube, the cave depth of Caved-tube and the hole diameter of K-tube and Porous Surface tube.
关键词
压差管
测量
流体
剪切力
壁面剪切力
tube of pressure difference measurement fluid shear stress
