气雾化制粉用Laval喷管结构优化研究

Design Optimization of Laval Nozzles for Gas Atomization Pulverizing

Laval喷管是影响雾化效率重要因素之一,为了其优化设计,本文利用正交试验方法以及workbench和fluent软件进行建模和计算喷管马赫数云图,得出自行研发的紧耦性Laval喷管的最佳喉口直径﹑收缩角和扩张角的大小分别为0.4 mm﹑7°和12°以及喷管出口马赫数大小为3.796。通过对因素结果分析,得出扩张角对喷管性能最敏感且喷管出口速度随着扩张角的增大而增大;收缩角对喷管性能影响不明显;喷管出口速度随着喉口直径的增大而减小;通过对紧耦性Laval喷管的研究,为气雾化喷管的优化设计提供依据。

Laval nozzle is one of the factors to affect the atomization efficiency.In order to optimize the design and study of Laval nozzles,the modeling of nozzles and the calculation of Mach number nephogram were carried out in this article by using the orthogonal test method and the software Workbench and Fluent;on the basis of which,it is resulted that the most optimal throat diameter,contraction angle and expansion angle are 0.4 mm,7 degree and 12 degree respectively for self-developed close coupling Laval nozzles,and also the Mach number for nozzle outlets is 3.796.By analyzing the effect of factors,it is concluded that the expansion angle is most sensitive to the effect on nozzle performances and the nozzle outlet velocity increases with the increase of expansion angles;the contraction angle is not obviously effective on nozzle performances;the nozzle outlet velocity decreases with the increase of throat diameter sizes.The study of close coupling Laval nozzles provides a basis for atomized-nozzle design optimization.