改性沥青搅拌罐涡轮搅拌器不同叶片安放角的影响分析

Impact of different blade placement angle on turbine stirrer in a modified asphalt mixing tank

为了提高搅拌设备内SBS改性沥青的搅拌混合效果,从而能够明显改善改性沥青的力学性能和感温性能,提高公路使用质量。由于SBS改性沥青混合属于固-液两相,通过采用计算流体软件CFD对不同叶片安放角下的开启涡轮搅拌器进行数值模拟,分析30°、45°、66°和四直叶涡轮搅拌器的速度矢量图和综合速度云图,并分别比较其不同涡轮搅拌器的轴向速度、径向速度和切向速度。研究结果表明,四直叶涡轮搅拌器搅拌流型以径向流为主,且产生双循环涡流,圆周带动能力强,混合效果较差; 30°、45°和66°斜叶涡轮搅拌器是以轴向流为主,且其速度最大值出现在搅拌器叶片端部。

In order to improve the mixing and stirring effect of SBS modified asphalt in the mixing equipment,increase the mechanical properties and temperature susceptibility of modified asphalt,the impeller of open turbine with different blade placement angles was numerically simulated by CFD software.Velocity vectors and integrated velocity nephograms of turbo stirrers with 30°,45°,66°and four straight blades were analyzed.Then the axial velocities,radial velocities and tangential velocities of these turbine stirrers were compared respectively.The results show that the mixing flow pattern of the four-blade turbine stirrer is mainly radial flow,and generates double-cycle vortex,which has strong circumferential driving ability and poor mixing effect.The inclined-blade turbine stirrer of 30°、45°and 66°are mainly axial flow,and the maximum velocity occurs at the stirrer blade tip.