涡轮叶片内部通道流动换热算法改进

Improvement of Flow and Heat Transfer Algorithm for Turbine Blade Internal Channel

在使用工程计算方法对涡轮叶片温度场进行计算时,往往将叶片内流通道简化成光滑或带肋的换热管元件,容易忽略各内流管段之间的影响,造成计算得到的叶片3维温度场与真实温度场存在较大差异。针对上述问题,为了提高对涡轮叶片3维温度场模拟的准确度,对涡轮叶片内流通道的换热流动算法进行改进。考虑涡轮内部蜿蜒通道中弯转区和弯转效应2种因素对涡轮内部流动换热的影响,使用试验得到的数据对2种因素影响区域的换热情况进行修正,利用修正后的算法对某工作叶片进行温度场计算,并对修正前后叶片温度场进行了对比分析。结果表明:采用修正后算法得到的蜿蜒通道内的气体温度相较于修正前算法得到的沿程升高更多,修正后算法求得的叶片整体平均温度降低,最大温差增大。

When using engineering calculation methods to calculate the temperature field of turbine blades,the internal flow channel of the blade is often simplified into smooth or ribbed heat exchanger tube elements,making the influence between segments of the internal flow channel ignored,resulting in significant differences between the calculated 3D temperature field of the blade and the actual temperature field.In view of the above problems,to improve the accuracy of the 3D temperature field simulation of turbine blades,the flow and heat transfer algorithm of the turbine blade internal flow channel was optimized and improved.Considering the influence of the two factors,the bending zones of the serpentine channel and the bending effect,on the internal flow and heat transfer of the turbine blade,experimental data were used to correct the heat transfer characteristics of the regions affected by the two factors.The corrected algorithm was used to calculate the 3D temperature field of a rotor blade,and a comparative analysis was conducted on the temperature field of the blade before and after correction.The results show that compared with the original algorithm,by using the corrected algorithm,the temperature increase of the gas along the flow path of the serpentine channel is higher,the overall average temperature of the blade is lower,and the maximum temperature difference is higher.