加力燃烧室防振屏的试验研究

 本文从工程实用的角度上研究了合理地选择涡轮喷气发动机加力燃烧室防振屏的结构参数,通过加大声学共振容腔和屏板开孔面积比,使防振屏在较宽广的频率范围内有尽可能高的吸振系数;使防振屏的几何形状过渡平缓,二股气流沿壳体周向趋于均匀,避免在防振屏波谷处气体分离产生涡卷而导致形成两温条带,减少周向温差,减小热应力,使加力燃烧室壳体壁温保持在材料许用温度以下,从而保证了加力燃烧长期可靠地工作。

EXPERIMENTAL RESEARCH ON PERFORATED ACOUSTIC LINERS IN TURBOJET ENGINE AFTERBURNERS

The reasonable choice of construction parameters for perforated acoustic liners in turbojet engine afterburners was investigated from the engineer's point of view. The perforated acoustic liner should have as much as possible high oscillation absorptivity in a quite wide frequency range by increasing the volume of acoustic resonant space and perforated area ratio of the shield. The smooth geometry of the liner can make the secondary flow uniform around the outer chamber shell and, therefore, avoid high temperature stripes proceeding from the gas separated-flow vortex at the wave valley on the perforated acoustic liner. Consequently, the circular temperature difference and the thermal stresses of the shell can be decreased, and the wall temperature of the afterburner shell can be kept down below the allowable temperature of its material. As a result, the afterburner can operate reliably for a long time.