小展弦比机翼加装格尼襟翼的低雷诺数试验

Test of low aspect ratio wing equipped with Gurney flaps at low Reynolds numbers

通过风洞试验研究了在低雷诺数下加装格尼襟翼的小展弦比机翼气动特性，机翼展弦比为1．67，格尼襟翼为1％～4％弦长高度，试验雷诺数分别为2．0×10。和5．0×10。．天平测力和表面测压的试验结果表明：低雷诺数下小展弦比机翼加装一定高度的格尼襟翼后，升力系数明显提高，加装1％弦长高度的格尼襟翼还能够提高机翼的升阻比．这是因为在试验雷诺数下，合适高度的襟翼在提高了机翼升力的同时并未显著增大机翼阻力．对比不同试验雷诺数下格尼襟翼的作用效果，表明格尼襟翼能够减少低雷诺数气流分离的不利影响，并且在较小的雷诺数下这种作用更加显著．关于格尼襟翼对低雷诺数层流分离现象的影响，还需薯涌讨细琦的浦场显示枯术讲行研窬．

Aerodynamic characteristics of low aspect ratio wing equipped with Gurney flaps were studied by wind tunnel test at low Reynolds numbers of 2.0 X 10s and 5.0 ）〈 10s. Aspect ratio of the low aspect ratio wing was 1.67, with 1%-4% chord height Gurney flaps. Balance force measurements and surface pressure distribution investigation were im plemented. The results suggest that lift coefficient of the low aspect ratio wing equipped with Gurney flaps was improved significantly at low Reynolds number. The lift drag ratio of wing was improved also when the wing was equipped with 1% chord height Gurney flaps. This is due to the increased lift of the wing introduced by the suitable height of the Gurney flap, while the drag has not been increased significantly at the Reynolds numbers in test. Comparing the effect of Gurney flaps with different Reynolds numbers in test, it indicates that Gurney flaps can diminish the negative effect of flow separation at low Reynolds num ber, and this mechanism takes more effect when the Reynolds number is lower. It requires more fine flow visualization technique to study the impact on the laminar separation phenom enon of wings with Gurney flaps at low Reynolds numbers.