微型燃气轮机燃烧室流场结构及燃烧特性的初步优化

Preliminary Optimization of Flow Structure and Combustion Characteristics in the Micro Turbine Combustor

为了改进微型燃气轮机结构,优化燃烧室性能,采用UG及Ansys软件对微型燃气轮机燃烧室进行几何建模、网格划分、数学及物理模型建立。通过热态数值模拟,研究了叶片数目为12、18、24、30以及叶片安装角度为40°、45°、50°、55°时的燃烧室内流场及燃烧特性。模拟结果得出:随叶片数目及安装角度的增加,燃烧室内甲烷燃烧效率基本不变,均可达99%以上,总压恢复系数降低,出口温度分布因子降低,圆筒内壁温度升高,但一氧化氮排放无法降低。最终选择叶片数目为24、安装角度为45°作为优化结果。

To improve the structure and optimize the performance of the micro turbine combustor,UG and Ansys were used to complete geometry modeling,meshing,establishing mathematical and physical model. Through thermal numerical simulation,flow field and combustion characteristics of the combustor were studied when the numbers of blades were 12,18,24,30 and the angles were 40°,45°,50°,55°. Simulation results and conclusions: with the number and angle of blades increasing,combustion efficiency is essentially the same,up to 99%,total-pressure recovery coefficient decreases,temperature distribution factor at the outlet is lower,cylinder wall temperature rises,but Nitric oxide emissions can not be reduced. The final choice as the optimization results for the number of blades is 24 and the angle is 45°.