The effect of molecular weight, molecular weight distribution, molecular structure of the polymer and behavior of the crude oil on drag reducing efficiency are represented.
本文讨论了减阻剂聚合物的分子量、分子量分布、分子结构以及不同物性的原油对减阻率的影响。
The mechanism and methods of viscosity drag reduction are briefly discussed. Some of its applications for saving energy and materials, improving efficiency or reducing noise and vibration are given.
本文综述了几种粘性减阻方法及其减阻的机理，联系了其在水相、油相中节约能源、材料，提高速度和效率等方面的应用。
The wing sails with 3.1 percentage of essential wing area have observable efficiency in reducing induced drag. The factors of the induced drag were reduced by 20 percent.
总面积为3．1％基本翼面积的翼尖帆片对减少诱导阻力具有明显效果，诱导阻力因子减小20％左右。
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