基于冲击冷却改型的燃气轮机静叶传热特性研究  

Study on Heat Transfer Characteristics of a Turbine Vane Based on Jet⁃Impingement Cooling Structure

作　　者：刘海清 罗璐 沈逸文 LIU Haiqing;LUO Lu;SHEN Yiwen(Shanghai Electric Gas Turbine Co.,Ltd.,Shanghai 200240,China)

机构地区：[1]上海电气燃气轮机有限公司,上海200240

出　　处：《热力透平》2024年第4期240-245,共6页Thermal Turbine

摘　　要：为了改善某透平静叶吸力侧顶部的局部高温状况,延长叶片服役寿命,利用耦合传热计算方法对该静叶进行了冷却结构优化改型设计和传热特性分析。将原型的数值模拟结果与服役机组的叶片状况进行了对比,结果验证了该数值方法的准确性。在此基础上采用了具有不同的孔排布方式、孔直径和孔数的6种方案,开展了中部冲击改型的方案比较,研究了冲击改型下的静叶流场与传热特性。结果表明:冲击冷却能有效消除该静叶吸力侧顶部的高温区;受叶片气动外形影响,相比于均布型冲击孔的排布方式,尾缘密集型排布方式可以在更小的冷却流量下获得更低的叶片表面温度,但叶片顶部温度仍略高于周围区域,冷却流量大时,吸力面根部容易向50%叶高处迁移,导致横流效应;根顶密集型冲击孔排布方式可以缩小叶片顶部和根部的高温区范围,降低最高温度值,冷却流量大时能弱化上述横流效应,在叶片根部至50%叶高处范围内均取得了很好的冲击冷却效果,是改善该透平服役状态的最优排布方式。研究结果可以为改进该类透平静叶的冷却结构设计,延长其服役寿命提供参考。In order to improve the situation of the local high temperature zone at the top of the suction side of a turbine vane and increase its service life,the conjugate heat transfer(CHT)method was employed to optimize the cooling structure of the vane,and its heat transfer characteristics were analyzed.The accuracy of the numerical method was verified by comparing the numerical simulation results of the prototype with the in⁃service unit.Then six different impingement⁃cooling arrangements with different arrangements,diameters and numbers of jet holes were proposed and compared.The flow field and heat transfer characteristics of the vane were studied.The results indicated that impingement cooling structure could effectively eliminate the high temperature zone at the top of the suction side of the vane.Due to the influence of the aerodynamic shape of the vane,compared to the uniform⁃hole layout,the dense⁃hole layout at the trailing edge could achieve lower surface temperature at a smaller cooling mass flow rate,but the temperature of the vane top was still slightly higher than the surrounding area.Meanwhile,when the cooling flow mass was high,the suction surface root tended to migrate to the 50%of the vane height,leading to cross flow effect.The arrangement of dense⁃hole layout at the top and the root could reduce the range and maximum temperature value of the high⁃temperature zone at the top and root of the vane,and could weaken the cross flow effect with high cooling mass flow rate,achieving good cooling effect from the root to 50%of the vane height.Therefore,it was the optimal arrangement to improve the service state of the vane.The research results can provide reference for improving the cooling structure of vanes in the same type of turbines and increasing their service life.

关 键 词：耦合传热 透平静叶 冲击冷却 

分 类 号：TK474.7[动力工程及工程热物理—动力机械及工程]