中文摘要：

采用三维全可压缩大涡模拟方法分析了不同进气／进口压力对预混燃烧不稳定性及NOx排放的影响．结果表明：由于内部剪切层的不稳定性，不同进口空气压力时，燃烧室内中心回流区的边界形成2个螺旋形的进动涡核；较高的进口空气压力时，燃烧室内更容易发生燃烧不稳定现象．增大进口空气压力使得燃烧室内温度升高，反应物浓度增大，NOx排放量升高．

英文摘要：

Effects of inlet pressure on the combustion instability and NOx formation characteristics of premixed flame were studied using a three-dimensional full compressible large eddy simulation （LES） approach. Results show that, due to the instability of inner shear layers, two spiral-shaped precession vortex cores would form at different inlet pressures on the boundary of center recirculation zone in the combustion chamber, where instable combustion is easy to occur at higher inlet pressures. High inlet pressure helps to improve the temperature in combustion chamber and raise the mole concentration of reactants, which would result in high concentration of NOx emission.