风力送丝系统中S型弯管内纯空气流的阻力受管形影响研究

Study on the effect of tube-shaped on resistance of air flow inside S-elbow in tobacco pneumatic conveying system

为减少烟丝气力输送系统阻力损失以提高系统风力利用率,对系统中S型弯管的流场特性与阻力特性进行了研究.用Fluent软件模拟了纯空气通过S型弯管时管内流场特性及S型弯管内的压降,分析了弯管夹角(θ)、弯管曲率半径(r)与料管直径(D)之比对S型弯管流场特性及其压降的影响.研究发现,单位长度S型弯管的压降随弯管夹角及弯管曲率半径增大而减小,弯管夹角(θ)和弯管曲率半径(r)与料管直径(D)之比的最佳取值范围分别为θ≥75°和6≤r/D≤15.所得到的结论为优化设计S型弯管提供了参考.

Study on the flow property and resistance characteristic of S-elbow is beneficial to reduce pressure loss of pneumatic conveying system, and improve utilization ratio of wind power. The flow characteristic and the pressure loss of S-elbow with different elbow angel and curvature radius are simulated by the fluent. The simulation results show that the gradient of pressure decrease when the angle increased and the optimum angle is 75 degree, and the unit length pressure drop of S-elbow decrease with radius increasing, the ratio between the radius of bend and the diameter of pipe should be ranged from 6 to 15. The simulation results provided reference for the design and engineering application of S-elbow in tobacco pneumatic system.