PECULIARITIES OF FORMING OF MONOLITHIC PANELS WHILE MAKING THE WING OF THE WING WITHOUT TECHNOLOGICAL CONNECTORS

The subject of the study in the article is the problem of the exact forming of individual panels in the wingbox assembling process without technological spanwise joints of the wing. The goal of the study is to create a model for an oblique curvature forming of the stiffened panels, which provides high tolerance of the panel shape and a given position of the bending axis. Objectives: a development of procedures that improve the tolerance of panel forming, reduce the amount of fitting work, reduce labor intensity, and increase productivity. The methods include: local deformation forming method by means of applying bending moments at the sweep angle and an additional correction angle, which takes into account the elastic effects of the stiffened panel; as well as numerical analysis of the forming process using ANSYS simulation. The following results are obtained. The created model of oblique curvature forming of the stiffened panels provides the capability to model the process of panel forming with the given tolerance. Using numerical approach, the magnitudes of the normal stresses and strains, deflections of the panels formed by applying local moments at the sweep angle, at the maximum load applied as well as their residual values. The results of the experiment of panel forming by unconstrained bending and local deforming on aluminum alloy samples are described. Conclusions. The scientific novelty of the research is as follows: the developed model of the stiffened panel forming process for a swept wingbox proofed the high efficiency while achieved the specified tolerance; by comparing the results, obtained by different methods, the advantages of the model applied to the local method of achieving the wing panel oblique curvature are verified. The local forming method by applying local bending moments to the ribs of the panel allows us to correct the oblique angle and achieve high tolerance due to the iterative procedur