环形射流泵结构优化设计

Structure optimization of annular jet pumps

运用DOE和CFD技术,以寻求环形射流泵效率最大时的最佳结构尺寸组合.试验射流泵模型原型取自真实试验,面积比1.75.首先对计算方法的可靠性进行了验证,在试验设计方法指导下,以最高效率为原则安排了多次试验,确定了4个主要因子,即流量比q、吸入室收缩角α、相对喉管长度l t及扩散管扩散角β,分别计算了射流泵在多种结构尺寸组合下的内部流动.借助统计分析软件对试验数据进行处理,确定各结构参数对射流泵性能影响的重要程度,找出最优的结构组合.结果表明该方法取得了很好的效果,试验设计预测最大效率36.3%与CFD模拟结果35.8%非常接近.影响泵性能的主要结构参数中,相对喉管长度比扩散管扩散角、吸入室收缩角更为显著,双因子间的交互作用比因子单独作用更为明显,为环形射流泵进一步优化设计,确定其合理的工作范围提供了依据.

With the method of DOE( the design of experiment method) and CFD,the optimum structure parameters combination of an annular jet pump( AJP) was mainly investigated for the maximum efficiency. The AJP model designed by previous researchers,with the area ratio 1. 75,was adopted as the simulation prototype. The experimental data of the performance were used to validate the simulation results. Based on DOE,four main factors,namely the flow ratio q,the relative throat length l t,the included angles of the suction chamber α and the diffusion angle in diffuser β,were selected for the optimization of the efficiency,and series of experiments were carried out to study the inner flow of pump with different structure parameters combination. Then,the significance of structural parameters to the AJP performance was ascertained and the optimum structure parameters combination was obtained by means of statistic software package. The results confirmed the availability and effectiveness of the method that the maximum efficiency 36. 3% from DOE is nearly the same with the corresponding results35. 8% from CFD. Moreover,among all the main structural parameters impacting on AJP performance,the influence of the relative throat length is considerably greater than that of the included angle of the suction chamber and the diffusion angle in diffuser. It can be concluded that the effects of two-factor interactions are more significant than that of one factor acting alone. The basis for the further optimization and determination of reasonable working range of AJP is provided.