低背鳍对细长平板三角翼大迎角空气动力的影响

 对细长体平板三角翼和加上两个不同高度背鳍后的组合体在低速风洞进行了六分量天平测力实验，三角翼后掠角82.5°，背鳍当地高度与模型当地半展长比值分别为0.3和0.6，实验迎角范围12°～32°，包括1.66×10.6和2.33×10.6两个雷诺数。实验结果表明：0°侧滑角下，在翼面上发生旋涡破裂前，单独细长平板三角翼的横向力及横向力矩在实验迎角范围内始终为零；加上两个不同高度的低背鳍后，在一定的迎角下，三角翼的横向力及横向力矩开始不为零，流场定常；在更大的迎角下，流场变得非定常。实验结果初步验证了前人关于细长锥体分离涡的稳定性理论，并给出了旋涡失稳后，随着迎角的增大，流场进一步发展的状态。

Effect of Low Dorsal Fin on Aerodynamic Characteristics of Slender Delta Wing

A force measurement experimental study was performed on a flat plate delta wing of 82.5° sweep angle and combination of the identical delta wing with low dorsal fins. The test was conducted at the low speed wind tunnel using a six-component internal strain gage balance at 12°~32° angles of attack. Two fins of different heights were tested, and the ratios of the local fin height to the local wing semi span were 0.3 and 0.6 respectively. There were two Reynolds numbers, 1.66 ×10.6 and 2.33×10.6,used.