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六种小环形间隙的实验结果表明,光滑同心二重管内的流动摩阻系数λ仅是雷诺数 Re 的函数,实验值与半经验公式λ=0.321/Re~(0.25)基本一致。实验是在 Re=10~4-8×10~4范围内进行的.实验数据同国外有关公式和数据进行了比较。对不同节距 p,不同槽宽 B和不同间隙 S 的36个迷宫进行了实验研究,其中还包括了不等节距迷宫。给出了 S/B-λ 和 B/p-λ 的关系曲线。在 S/B(?)0.1-0.2,B/p(?)0.8时,迷宫具有最大的阻力系数。还研究了环形间隙的偏心和迷宫齿倒角问题。偏心及倒角都使流动阻力系数下降,流量增加。
The experimental results of six kinds of small annular gap show that the flow friction coefficient λ in smooth concentric double tube is only a function of Reynolds number Re. The experimental value is basically consistent with the semi-empirical formula λ = 0.321 / Re ~ (0.25). The experiment is carried out in the range of Re = 10 ~ 4-8 × 10 ~ 4. The experimental data are compared with the relevant foreign formulas and data. 36 labyrinths of different pitches p, different groove widths B and different clearances S were studied experimentally, including unequal-pitch labyrinths. The curves of S / B-λ and B / p-λ are given. At S / B (?) 0.1-0.2, B / p (?) 0.8, the maze has the greatest drag coefficient. The eccentricity of the annular gap and the chamfering of the labyrinth teeth have also been investigated. Eccentricity and chamfer all reduce the flow resistance coefficient and increase the flow rate.