喷嘴数目对多喷嘴射流泵性能影响的数值分析

Abstract

射流泵结构简单，在某些特殊工艺流程中具有明显的优越性和不可替代性，但传能效率低，通过合理设计结构可改善其性能。利用前处理软件GAMBIT建立多喷嘴射流泵三维空间模型，在不改变面积比、流量比及出口压力的前提下，应用CFD软件——FLUENT，对均匀分布、水平射流出流的、具有不同喷嘴数目的射流泵内部流场分别进行数值模拟计算，得到了多喷嘴射流泵内部流场随喷嘴数目的不同而变化的规律。通过对数值模拟结果进行分析，发现：喷嘴数目对流体轨迹的影响很大，喷嘴数目决定着回流区域的大小。射流泵的性能不是随着喷嘴数目的增加而呈单调上升趋势。该结果为多喷嘴射流泵的设计及研究提供参考。 The structure of jet pump is simple, and it cannot be replaced in some special technological process. But the efficiency of energy transfer of jet pump is low, and jet pump performance can be improved by reasonable structural design. The three-dimensional spatial model of multi-nozzle jet pump was established by GAMBIT software. Under the premise of certain area ratio, flow ratio and outlet pressure, the Computational Fluid Dynamic (CFD) software—FLUENT was used to calculate the inner flow field of multi-nozzle jet pump with uniform distribution and horizontal jet flow and different nozzle numbers. The rule of inner flow field of multi-nozzle jet pump is changed with the number of nozzle. According to the simulated flow field, the result shows that the number of nozzle has much effect on the fluid track and the number of nozzle determines the size of backflow region. The performance of the jet pump is not increased with the increase of nozzle numbers; it is not a monotonous rising trend. The result will provide reference for design and study on multi-nozzle jet pumps in the future.