进口速度畸变对轴流风机性能影响的全周数值研究

Full-annulus Numerical Study of Performance in an Axial Fan with Inlet Velocity Distortion

采用全通道数值模拟方法,通过设置周向角度相同、径向位置不同的速度畸变区域,分析了畸变条件下低压轴流风机性能及流场的变化规律。计算结果表明,该方法可以清晰描述流场参数的分布情况,设置的进口速度畸变方式会使风机效率降低,静压升变大,转子进口相对气流角分布与叶型极不匹配,造成进口冲角绝对值较大,叶栅通道内的流动恶化,流动损失增加,并且风机出口的压力沿周向分布的不均匀性增强。

Different radial arrangements for the producing of the velocity distortion were put forward at the same circumferential position on the inlet surface of the calculation region,and the effects of the distortions on the performance as well as on the detailed flow-field in an axial-flow fan were investigated with the method of full-annulus numerical simulation.It’s found that this method can clearly describe the distribution of parameters of the flow field,these kinds of distortion can reduce the efficiency somewhat while increase the static pressure rise.The rotor inlet relative flow angle does not match with the blade profile,leading to the in-crease of the absolute value of the attack angle and the flow deterioration in the cascade,thus the flow loss becomes larger.Further-more,the total pressure on the outlet surface of the calculation region is more non-uniform along the circumferential direction.