【摘要】 流场遍历是流场混合的必要条件。根据立式捏合机混合釜内螺旋桨刃尖的运动特征,定义了穿越、遍历率和遍历时间等基本概念;提出了用遍历率和遍历时间来评价流场遍历性能;分析了螺旋桨的自转公转转速比对流场遍历率和遍历时间的影响。研究结果表明:螺旋桨的自转公转转速比对流场遍历性能具有极大影响,并可以通过比较不同转速比所对应的遍历率大小得到较优的螺旋桨的自转公转转速比;采用双螺旋桨能明显提高系统遍历率,降低遍历时间。更多还原

【Abstract】 Ergodicity of a flow field is the necessary condition for mixing of the field.Based on kinematic characteristics of tips of screw blades in the mixing tank of a vertical kneader,definitions of crossing,rate of ergodicity,and time of ergodicity were defined,evaluation methods of ergodicity performance of a flow field by means of rate of ergodicity and time of ergodicity were presented,and influences of rate of self-revolution and planet-revolution(RSP) the screw blades on rate of ergodicity and time of ergodicity were analyzed.Results showed that RSP of the screw blades affect ergodicity performance of the field dramatically,optimal RSP can be obtained through comparing values of ergodicity at different RSPs,and rate of ergodicity,of the fluid system,can increase and time of ergodicity decrease obviously by adopting double screw blades.更多还原