Composite vertical tail main box section wing spar root joint and design method considering damage safety

Abstract

The invention provides a composite material vertical tail main box section spar root connection structure and design method considering damage safety, relates to the technical field of aircraft design, and can improve the composite material vertical tail without changing the load-bearing form of the joint structure. The damage safety performance of the root of the spar of the tail main box section improves the reliability of load transmission, reduces the workload of parts processing and assembly, improves the utilization rate of raw materials, and reduces costs; this connection method does not change the load transmission form of the joint structure Next, considering the damage safety performance of the joint structure, the one-piece titanium alloy joint is split into two-piece back-to-back titanium alloy joints; the vertical tail main box section spar is connected to the rear fuselage through two pairs of two-piece titanium alloy joints on the left and right; The two-piece titanium alloy joints are respectively connected to the spar web to form a double shear connection structure and improve the reliability of the connection structure. The technical scheme provided by the invention is suitable for the connection design of the root of the wing spar of the main box section of the vertical tail of the aircraft.

Description

[Technical field][0001]The present invention relates to the field of aircraft design, and more particularly to a structure and design method for the root of the front tail of the double-end tail of the reimbursement.【Background technique】[0002]The commercial aircraft is transmitted, the manipulation load and inertial load are transmitted to the rear body by the docking structure of the root of the vertical tail main box. According to the relevant requirements of CCAR25, the docking structure must be able to withstand the limit load without permanent deformation, and the damage safety design must be used, so that it is still able to withstand the limit load when any single joint or structural element is damaged, and must be in the entire service life of the aircraft Avoid disasters due to fatigue, corrosion or accidental damage, must meet the requirements of detachability and interchangeability. Therefore, the structural design of the root connection zone connecting area and the rear...

AI Technical Summary

Problems solved by technology

However, there are obvious shortcomings. The thickened design of the joint places higher requirements on the laying process and molding process. Once the overall joint is damaged, it is very difficult to replace and repair, and it is not conducive to the guarantee of the damage safety design requirements.

In 2001, in New York, USA, flight AA587 (Airbus A300) was due to damage to one of the integral joints at the root of the vertical tail. After the load was redistributed, the vertical tail completely fell off, resulting in the death of 251 passengers and 9 crew members on board.

[0009] In the existing connection scheme at the root of the rear beam of the vertical tail main box section, from the perspective of damage safety design, once the integral titanium alloy joint 2 is damaged or cracked somewhere, under the action of high-cycle fatigue load, it is very likely to cause joint damage. The overall damage, so the damage safety performance is not good; the beam web and joint vertical reinforcement are single-shear connection structures, and the reliability of load transmission is poor; ) is connected with the integral titanium alloy joint 2, which increases the manufacturing workload and assembly steps of the parts, and increases the manufacturing cost and assembly cost

At the same time, for this solution, the size of the titanium alloy integral joint at the root of the back beam is large, the integral joint process is difficult to manufacture, the product scrap rate is high, the required blank size is large, and the material utilization rate is low, which further increases the manufacturing cost.

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