Research And Realization Of Modeling Method Of Blended Wing Body

Nowadays, most mechanical systems put forward higher demands for components and parts. Despite the complexity of surface modeling, it needs to guarantee a smooth connection between surfaces. The geometric continuity between surfaces is always a difficulty in computer aided design.Based on a complex aircraft modeling system, this paper studies modeling method of blended wing body, which involves surface modeling, surface interpolation, and surface splicing technology. The key for implementation of blended wing body is to guarantee the smooth connection between surfaces. First, this paper presents the requirements of blended wing body based on some definitions associated to the aircraft, and then uses some traditional approaches to realize the blended wing body. Besides, the limitations of these methods are also pointed out. Second, with the previous research achievements, this paper proposes a new method to achieve the blended wing body, which is based on surface splicing technology. The way utilizes the transition surface to ensure wing-body fusion, which can't ensure the continuity between the fuselage and wing directly. First, It generates transition surface with the design parameters of transition surface. Then it get the surface set which intersects with the transition surface,and is locate on the fuselage. Second, it interpolates a NURBS surface which approximate the surface set. Lastly it makes surface splicing between the NURBS surface and the transition surface to ensure the continuity of surfaces. Because the NURBS surface approximate the body surface, it ensure the continuity of the body surface and the transition surface which is adjusted to the new surface. It applies the same algorithm between the transition surface and wing, and realizes the smooth connection. But here is no longer a transition surface which is modified, but the wing surface. Finally, it guarante the smooth among the fuselage, the transition surface and the wing.It is easy to realize the surface smooth stitching algorithm which has high computational efficiency and certain actual engineering significance.The method is adopted in our CAD system for designing the shape of the complex aircraft modeling system, and the application effect is good.