掺混孔调整对燃气轮机DLN燃烧室性能影响研究

The Effect of Dilution Hole Diameter on the Performance of a Gas Turbine DLN Combustor

掺混孔是影响燃气轮机燃烧室出口温度分布的重要设计参数。针对多喷嘴DLN燃烧室开展整体数值计算,探讨了掺混孔尺寸调整对燃烧室性能的影响规律。研究表明,减小掺混孔一方面可使进入燃烧室头部的空气量增多,燃烧峰值温度和平均温度显著下降,有利于改善燃烧特性,另一方面削弱了掺混孔射流卷吸效应,使火焰筒金属壁面的高温区范围大幅缩小。但是,减小掺混孔将增大燃烧室总压损失,在总体性能和透平冷却设计中应予以关注。多喷嘴DLN燃烧室出口温度分布受掺混孔调整的影响较小,更多取决于过渡段内部流场结构特征。

The dilution hole is an important design parameter affecting the outlet temperature distribution of the gas turbine combustor.In this paper,the integrated numerical analysis of a multiple nozzle DLN combustor was carried out,and the influence of dilution hole diameter adjustment on combustor performance was discussed.The results show that,by reducing the dilution hole,the amount of air entering the head of the combustor increases,which could significantly reduce the peak temperature and the average temperature,which is beneficial to improve the combustion performance.At the same time,the entrainment effect of the dilution air jet is weakened,and the high temperature area of the combustor liner is greatly reduced.On the other hand,reducing the dilution hole will increase the total pressure loss of the combustor,which should be paid attention to in the thermal performance and turbine cooling design.The outlet temperature distribution of the multiple nozzle DLN combustor is less affected by the adjustment of the dilution hole,and more depended on the internal flow structure characteristics of the transition piece.