等腰三角形管道进口段流动阻力研究

本文首先利用Л.В.Канторович变分方法求出了等腰三角形管道不可压缩流体层流完全发展段流动速度的变分解,并且给出了压力损失的理论计算值与实验值.继而,本文推求出适用于各种顶角的等腰三角形管道进口段流动的速度分布模型和附加压力损失系统以及进口段长度计算方法.并对两种顶角(2α=45.1°,60°)的等腰三角形管道进口段流动进行了具体计算和实验.本文的理论分析与其他作者的理论分析比较表明,本文的分析结果具有很高的精度和广泛的实用性,并与作者的实验结果吻合较好.

A Study on Flow Resistance in the Entrance Region of Isosceles Triangular Ducts

In this paper the varitaional solution of velocity profile for an incompressible laminar and fully developed flow in isosceles triangular ducts is derived by applying the kantovorich method. The theoretical and experimental results of pressure loss are also given. The velocity distribution model, additional pressure loss coefficient and calculating method of inlet length in the entrance region of isosceles triangular ducts are also derived, which are suitable for various kinds of vertex angles. The calculations and expriments arc also performed for two models-, the isosceles triangular ducts with vertex angles 2a = 45.1 and 2c=60. By the comparisons made between the theoretical analysis in this paper and those of other authors. It can be seen that the present analytical result is of high accuracy and wide practicability, and agrees well with the author's experiment.