进口速度畸变以及涵道比对波瓣混合器性能影响的试验研究

Experimental Investigation on Performance of Lobed Mixer with Effects of Inlet Velocity Distortion and Bypass Ratio

为了研究不同进口速度畸变以及涵道比对波瓣混合器性能的影响规律,以带进口畸变孔板的双涵道全环轴对称加力模型试验件为研究对象,采用五孔探针配合三维位移机构测量了不同涵道比下波瓣混合器后的三维流场。试验研究表明:随着波瓣混合器出口距离的增加,内外涵掺混速度先升高后降低,总压恢复系数逐渐降低,混合效率和推力增益逐渐升高;随着混合器涵道比的增加,流向涡及低温区域范围增大,混合均匀性下降,混合效率和总压恢复系数均降低;进口畸变峰值在上方时,气流加速掺混对推力增益有益,总压恢复系数更高,小涵道比混合效率更高;进口畸变峰值在下方时,扩压段壁面静压和中心锥锥体静压均较高。

In order to figure out how the inlet velocity distortion and the bypass ratio effect on the performance of lobed mixer,a two-flow annular axisymmetric afterburner test model with inlet distortion orifice plates was designed and a five-hole probe combined with a three-dimensional displacement equipment was employed to measure the three-dimensional flow field of different inlet velocity distortion and bypass ratio behind lobed mixer planes. The results show that with the increases of distance from the outlet of lobed mixer,the mixing velocity of core and bypass will increase at first then descend, and the total pressure recovery coefficient will decline,while the mixing efficiency and thrust gain will increase. The results also show that the increases of bypass ratio will enlarge the range of streamwise vortex and low temperature,while the mixing homogeneity,mixing efficiency and total pressure recovery coefficient will decline. When the inlet velocity distortion peak is on the top,the airflow will be accelerated mixing which is beneficial to the thrust gain and the total pressure recovery coefficient will be higher,and the mixture efficiency will be higher with a small bypass ratio. When the peak of inlet velocity distortion is at the bottom,both the wall static pressure of diffuser and the static pressure of center cone are relatively high.