大涵道比风扇转子的非定常数值模拟

为了更好地设计大涵道比风扇转子及外涵导叶(OGV),采用非线性谐波法对某大涵道比风扇转子及OGV进行了非定常和定常数值计算,2种计算方法获得的风扇外涵级的流量、增压比、绝热效率有一定差异,并分析了性能变化的原因。通过对其典型截面的非定常流场进行快速傅里叶分解,在频域内分析了风扇转子和OGV之间的转静干扰效应,以及交界面典型脉动量的周向波形,从频域的角度分析了影响性能的原因;同时观察到一些时域中难呈现的现象。结果表明:通过非定常数值计算,大涵道比风扇外涵级绝热效率曲线随时间变化呈现正弦曲线的形状,幅值约为0.59个百分点;风扇外涵级绝热效率最高、最低点分别出现在风扇尾迹通过静子通道的约3/4和1/4处。

Unsteady Numerical Simulation of High Bypass Ratio Fan

The unsteady and steady numerical calculation of a high bypass ratio fan and OGV were obtained by non linear harmonic method to design them better. The bypass flows pressure ratio, stage adiabatic efficiency of the fan which got from the two simulation methods were different, and the reasons were analyzed. Based on the Fast Fourier Transformation (FFT) of the typical profiles of the stage,the rotor-stator interactions between the fan and OGV were analyzed, and the circumferential distribution of typical unsteady perturbation was studied to give out the influences reason in the frequency domain. The phenomena hardly observed in the time domain can be discovered simultaneously. The results show that the stage adiabatic efficiency of the high bypass ratio fan is a sinusolid according to the time, and the amplitude value is about 0.59 percent according to unsteady numerical calculation. The maximum and minimum value of the stage adiabatic efficiency is located on 3/4 and 1/4 OGV that the fan wake passed through.