聚氨酯软管沿程摩阻损失计算新方法

A New Method of Friction Loss Calculation for Polyurethane Hose

运用材料力学和流体力学基本原理,建立了聚氨酯软管微元段数学模型,探究了管径与内压的变化规律,推导出聚氨酯软管考虑管线膨胀量的沿程摩阻损失计算新方法。利用国家消防装备质量监督检验中心提供的压力损失数据和我军某型输油管线的输送实验记录对新算法进行了验证,对比分析了不同沿程摩阻损失计算方法下长输管线的水力布站结果。结果表明,传统算法由于忽略了聚氨酯软管在承受内压后管径增大的效应,沿程摩阻损失随管线长度的增加而线性增大,计算误差较大;新算法考虑了软管内压升高时管径增大的因素,沿程摩阻损失随管线长度的增加而缓慢增大,比传统算法具有更高的精度,可以提高聚氨酯软管尤其是长距离管线运用的经济性,并可作为考虑管线膨胀因素时软管沿程摩阻损失计算的通用方法。

Based on the basic principles of both the mechanics of materials and fluids, an analytical mathematic model is constructed to reveal the relationship between the working head and the variation of the polyurethane hose's inner diameter. And a new method featuring the consideration of pipe expansion effects is derived to calculate the friction loss for polyurethane hose. Verification of the proposed method in this paper is made by utilizing the pressure loss data provided by the National Fire Equipment Quality Supervision and Inspection Center and the experimental records of transportation tests for a certain type of military hose line in our army. The pump station placement results from both the traditional and the new friction loss calculation methods are compared and analyzed. The results show that the traditional method ignores the hose's pipe expansion effects under working pressure and introduces a liner friction loss increment while the pipe length extends and will generate quite a significant error, while the proposed new method takes into account the expansion of hose with the increasing pressure and the friction loss will increase more slowly when the pipe length increases. The new method is more accurate than the traditional method and thus makes the application of polyurethane hose especially the long distance one more economical. The method has the potential to be an universal method for hose pipe, in which the pipe expansion effects must be taken in consideration.