弯掠动叶扩大稳定工作范围的实验研究

本实验利用两组轴流试验风机，每组分别为一台是常规（径向）动叶，另一台为弯掠动叶。一组保持它们具有（除弦长外）相同的几何参数和相同的转速（弯掠动叶中径处弦长增加量为２０．４％）；另一组具有相同的风机最高压比及其相对应的流量。在这两种条件下对每组风机进行了气动—声学性能的实验，其结果表明：具有弯掠动叶的轴流风机不仅改善了气动—声学性能，而且还大幅度地扩大了稳定工作范围。根据实验结果，对弯掠动叶扩大轴流风机稳定工作范围的机理进行了讨论。

AN EXPERIMENT ON ENLARGING STEADY WORKING RANGE OF SKEWED-SWEPT ROTATING BLADES

An experimental investigation on enlarging the steady working range of skewed-swept rotating blades has been completed.Two types of fan were compared,a fan with conventional (radial) rotating blades and other with the skewed-swept blades.One comparative group was carried out on the conditions of same rotating speed and geometrical parameters but median chord of the skewed-swept rotating was increased about 20 4%,another was carried out at same peak pressure ratio and flow rate.The results of aerodynamic-aeroacoustic performance testing of the groups show not only a noise reduction about 2-4 dB(A) overall,and an increase of aerodynamic efficiency for the skewed-swept blad,but also a great enlargement of steady working range (one group about 21%,other more than 22%).On the basis of the experimental results,the mechanism of the enlargement of steady working range for skewed-swpet rotating blades was analyzed.