基于两种模型的燃气轮机级内流场数值模拟的分析比较

CFD analysis and comparison of gas turbine by use of plane and sliding mesh model

借助Fluent软件,采用混合平面模型和滑移网格模型分别对某船用增压锅炉燃气轮机级内流场进行了数值模拟(CFD)分析,并对比了两种模型条件下燃气轮机级出口参数的变化规律。对比分析结果表明:非定常干扰因素主要来自动静叶片排间的相对运动和每个叶片排流场周向非均匀性引起的非定常流动,动静叶栅之间的非定常干扰因素是导致级出口参数不同于定常情况下的根本原因,从而进一步揭示了燃气轮机级内流动具有固有非定常性的物理本质。

With the help of the software Fluent, the simulation oi the cascade flow field in the gas turbine for supercharged marine boiler was made based on the mixing plane model and sliding mesh model. Then the parameters of cascade outlet under unsteady flow were compared with other parameters under steady flow. The interference caused by relative movement and nonuniformity along the circumference in cascade was the most important factor that leads to the unsteady flows in gas turbine. The parameters of cascade outlet under unsteady flow varied with other parameters under steady flow because of the unsteady interference between rotor and stator. The result reveals the physical nature of unsteady phenomenon in gas turbine cascade flow field.