Researches On Parametric Geometry Modeling And Profile Characteristics Analysis For Helicopter Blade Structure

Blade’s structure design is an important part of helicopter design. For a long period, it is based on section description which decides engineering drawing and three-dimensional geometrical modeling of the blade. However, this method leads to some problems, such as low efficiency, poor precision. According to the above problems, the paper proposes using section description defines components of the blade, and on this basis, a series of researches on blade automatic geometry modeling, structure characteristic and optimization for blade structure are done. In order to facility, a digital system is independently developed to support this method of blade structure design. The innovative points and main contents of this paper are summarized as follows:(1) The parametric definition methods of attachment filling, beam and trailing edge are discussed in detail. Centered on section description, a detailed definition scheme is formulated to express the message of every component.(2) For the complex internal structure, analytical formulations are derived by physical interpretation and reasonable simplification. Taking full advantage of the definition proposed, this method can integrate profile characteristic analysis with the parametric definition completely.(3) An optimum design method based on parametric components definition is put forward for composite blade structure. The structure optimization of blade is realized by calling the corresponding optimization software which sets component definition parameters as optimization variables, profile structure characteristics as the optimization goal and some certain constraint.(4) Based on the definition method proposed, the 3D geometric modeling of the attachment filling, the beam and the trailing edge are automatically realized by using geometric modeling theory and techniques.(5) A system realizing structure modeling on parametric definition and profile characteristics analysis of helicopter blade is developed independently, which can complete the whole blade design flow including parametric definition, geometric modeling and profile characteristics analysis.