旋流器流量分配对三级旋流流场特性的影响

Effects of Air Proportions on Flow Characteristics of Swirling Flow Generated by Triple-Swirlers

关键词:  流量分配  旋流数  三级旋流器  回流区  数值模拟  燃烧室

Key words:  Air proportion  Swirl number  Triple-swirler  Central toroidal recirculation zone  Numerical simulation  Combustor

摘要:

为探讨三级旋流器流量分配对旋流器出口流场的影响，针对旋向组合为“顺时针-逆时针-逆时针”，内级、中间级、外级旋流器旋流数分别为1.4，1.0，0.6的三级旋流器，开展了相同进口条件下不同流量分配方案的数值研究。研究结果表明:当内级旋流器流量分配一定时，随着中间级/外级气流流量比的增大，回流区轴向长度、径向宽度，回流率及旋流数逐渐增大；当中间级旋流器流量分配一定时，随着内级/外级气流流量比的增大，回流区轴向长度、径向宽度、回流率及旋流数逐渐减小；当外级旋流器流量分配一定时，随着内级/中间级气流流量比的增大，回流区轴向长度、径向宽度，回流率及旋流数逐渐减小。

Abstract:

The effects of air proportion on flow characteristics of swirling flow generated by triple-swirlers were discussed. The studied triple-swirlers have same rotational combination with clockwise inner swirler，counter-clockwise intermediate swirler，counter-clockwise outer swirler and the inner swirl number，intermediate swirl number and outer swirl number are 1.4，1.0 and 0.6，respectively. The numerical simulation methods were utilized to investigate different air proportion schemes in the same inlet condition. The numerical results show that the numerical results match well with the PIV measurements. And the numerical simulation can be employed to analyze the effects of air proportion on flow characteristics. For triple-swirlers with a constant inner air proportion，the length and width of the Central Toroidal Recirculation Zone(CTRZ)，as well as the recirculated mass flow rate and swirl number increase as the increasing ratio of intermediate air proportion to outer air proportion. For triple-swirlers with a constant intermediate air proportion，the length and width of the CTRZ，the recirculated mass flow rate and swirl number decrease as the increasing ratio of inner air proportion to outer air proportion. For triple-swirlers with a constant outer air proportion，the length and width of the CTRZ，the recirculated mass flow rate and swirl number decrease as the increasing ratio of inner air proportion to intermediate air proportion.