Design method for photosensitive resin wind tunnel model considering elastic deformation

A method for designing photosensitive resin wind tunnel model considering elastic deformation is presented to reduce the effect of model deformation caused by low stiffness of photosensitive resin on aerodynamic force experiment data in wind tunnel. Numerical calculation method for aeroelasticity is used to predict the model deformation under aerodynamic force and the original model shape is modified on the basis of the numerically calculated deformation, thereby the manufacture shape of resin model is obtained, so that the shape of model after deformation under aerodynamic force is same as the original model shape, thus eliminating the effect of photosensitive resin elastic deformation. Six F4 model manufacture shapes are designed on the basis of this method and the hypothesis that the airfoil of large aspect ratio wing is rigid. Six models are manufactured by using rapid prototyping equipment and tested in FL-21 transonic wind tunnel. Test data show that at design point, lift coefficients C_L of 4#, 5# and 6# models are in good agreement with the data of three foreign wind tunnels, and so are the pitch moment coefficients C_my of 1#, 2#, 3# and 5# models; at off-design points, C_L and C_my are quite different from the foreign data; drag coefficients C_d are greater than foreign wind tunnel results because of Reynolds number Re difference between this test and foreign wind tunnel tests. So, at design point, this method can obviously improve the aerodynamic force data precision of photosensitive resin wind tunnel model.