减阻聚合物薄膜的研制  

Development of Polymer Film Riblets for Drag Reduction

作　　者：于秀荣[1] 寇开昌[1] 林德宽[1] 

机构地区：[1]西北工业大学

出　　处：《西北工业大学学报》1993年第3期391-393,共3页Journal of Northwestern Polytechnical University

摘　　要：表面修形技术,可以减少飞机阻力而不改变飞机结构,应用方便,维护简单,颇有吸引力。国外70年代开始进行该技术的研究,大多数研究者利用Riblets(它是一些具有顺流向开槽的平面,而沟槽面的形状通常为三角形,沟槽深为几个微米)来减小紊流附面层阻力[1].When there is turbulent flow over a body, the drag increases sharply. Polymer film riblets with V grooves made by 3M company are widely used to reduce such drag, and tests show that the drag can be reduced by 7% [2]. The authors at NPU (Northwestern Polytechnical University) develop polymer film riblets with V grooves that give appreciable reduction of drag of turbulent flow over a boby under several different conditions. The aughors started to develop polymer film riblets in 1989. The height h of V groove is made smaller than its width s. S Varies between 0.04 mm to 0.39 mm. The cross-sections of V grooves for S=0.1,0.06, 0.04 mm (tyqes 91-1, 91-2, and 91-3) are shown in Fig. 1 (See Chinese text). On aluminum sheet models covered with NPU polymer film riblets with s=0.1, 0.06, 0.04 mm respectively, wind-tunnel tests are conducted. such wind-tunnel tests do not involve turbulent flow. The variation of relative drag reduction with speed of flow past the model are shown in Fig.2 (see Chinese text). In Fig.2, frepresents relative drag reduction; D, drag with polymer film riblets; D_drag without such riblets.fis computed by the following formula: f=(D-D_(?))/D_2×100 It can be seen from Fig.2, that all three types of polymer film ribets (91-1, 91-2, and 91-3) are effective in reducing drag in the case when the flow is not turbulent. Polymer film riblets with s=0.39 mm (type 90-1) are used to cover regions of wing surfaces of a model (scaled down from Chinese Y-7 transport aircraft by reducing all dimensions by a factor of 12) where turbulent flows exist. Wind tunnel tests conducted in an aerodynamics research institute in Haerbin show that for V=20 m / s and C_y=0, C_x is reduced by about 8.1 %. For different values of C_y, C_x is similarly reduced through the ues of type 90-1 polymer film riblets, as can be seen from Fig. 3, (see Chinese teat).

关 键 词：薄膜 减阻 高聚物 湍流 

分 类 号：TQ320.721[化学工程—合成树脂塑料工业]