离心级联管道结构和丰度不一致对分离级效率的影响

离心级联中一个分离级内部的混合损失主要来自两个方面：一是前后两级来流丰度不一致,二是物料沿管线输送时造成的流量分布不均匀.假设前后两级提供的物料流量已知,分离级的平均单机流量为单机额定流量,用迭代求解可得到分离级管道中的压强分布,从而可计算分离级的分离功损失,了解两种因素对分离级效率的影响程度.计算结果表明,分离级内部的分离功损失主要是由前后两级来流丰度不一致造成的,流量分布不均匀的影响很小;同时也间接说明将一个分离级中的分离装置的分离性能看成完全相同是合理的.

Influence of Pipe Configuration and Feed Abundances on the Separation Performance of a Separation Stage in a Centrifuge Cascade

The inner mixing loss of a stage in a centrifuge cascade results from two aspects, one of which is that the two incoming fluids from the previous and the next stages have different abundances, and the other is the nonuniformity of the pressures and feed flow rates due to the flow resistance in the pipes. When the mass flow rates from the previous and the next stages are given, and the averaged feed flow rate of a separation stage is the rated value, the distribution of the pressure and the feed flow rates in the pipe network and the performance of the stage can be determined, then the inequality of the abundances and the nonuniformity of the feed flow rates can be assessed, and their influence on the separation performance of the stage can be evaluated. The results show that the inner mixing loss of a stage is mainly caused by the abundance inequality, whereas the nonuniformity of feed flow rates has little effect. Adjusting the pipe diameters can make the feed flow rate in a stage become more uniform, but has very little influence on the separation performance.