叶片通用扭曲规律的拓展及抛物线流型的控制

摘要

The common twisting law of blade has been analyzed,and on this basis the common twisting law has been expanded. The parabolic flow pattern of blade has been proposed,which appropriately increases the energy head around the middle diameter and decreases the energy head around the top and bottom of blade.Using the expanded form of common twisting law,the tradition-al common flow pattern and parabolic flow pattern with different energy head distribution could be obtained by choosing different control coefficients.The parabolic flow pattern have been compared with the constant circulation flow and constant reaction flow pattern.The results indicate that the parabolic flow pattern could ameliorate the distribution of degree of reaction,relative speed’ s Mach number of inlet,outlet flow angle and turning flow angle.The disadvantages which are associated with common flow pattern including negative degree of reaction in blade bottom and exorbitant Mach number of suction relative speed have been conquered. Some problems such as exorbitant outlet flow angle and turning flow angle in the bottom of blade have been relieved.%分析了叶片一般通用扭曲规律，在此基础上拓展了一般通用扭曲规律。提出了叶片抛物线流型，适当增加了叶片均径附近的能量头，减小了叶尖与叶根附近的能量头。利用通用扭曲规律的拓展形式，通过选择不同的控制系数，能够获得传统常用流型以及不同能量头分布的抛物线流型。对比了抛物线流型与等环量、等反动度流型，结果表明，抛物线流型改善了反动度、入口相对速度马赫数、气流出口角、气流折转角的分布，克服了传统流型叶根易出现负反动度、叶尖入口相对速度马赫数过大等缺点，缓解了叶根气流出口角和气流折转角过大等问题。