具有密封凸顶和外偏心主圆弧的转子型线研究

Study on a New Rotor Profile with Convex Head for Radial Seal and Eccentric Main Circular Arc

为提高罗茨泵的容积利用率和容积效率,提出一种具有更高形状系数的密封凸顶和偏心圆弧的转子型线。基于普通的圆弧转子型线,通过偏心设计形成偏心圆弧转子型线,实现形状系数和容积利用率的提高;再由密封用凸顶圆弧的设计,进一步大幅提高形状系数和容积利用率;并就这三种圆弧转子的2叶形状系数和容积利用率,进行实例运算。结果表明,偏心转子的形状系数和容积利用率,较普通转子分别增效1.42%和2.24%;2叶凸顶转子凸顶半角1°~8°间的形状系数和容积利用率,较普通转子分别增效1.95%~7.26%和3.58%~11.84%,效果明显;且凸顶结构简单、易加工。为罗茨泵其他型线的增效设计提供了一种创新途径和方法。

For the need to increase effect of volume utilization rate and volume efficiency for roots pump,a new profile geometry of circular arc rotors with seal convex head and eccentric circular arc is proposed.Firstly,based on the profile geometry of common circular arc rotors,the eccentric arc rotor profile is formed by eccentric design to improve the shape coefficient and volume utilization ratio.Secondly,the shape coefficient and volume utilization rate are further improved by the design of convex top arc for sealing.Thirdly,The shape coefficient and volume utilization ratio of the two blades of the three circular rotors are calculated as examples.All results indicated that the percentage increase of shape coefficient and volume utilization rate with eccentric circular are 1.42%and 2.24%higher than common arc rotors.And the half angle of convex head is from 1°to 8°,the per centage increase of shape coefficient and volume utilization rate of two blades arc rotors with convex head is from 1.95%to 7.26%and from 3.58%to 11.84%higher than common arc rotors,increase effect was obvious.And the convex head structure is simple and easy to process.It is concluded that a new enhancement design is provided for other profile geometry in roots pump.