Probability theory based airplane composite structure detection interval determination method

A technology for structural inspection and composite materials, which is applied in the fields of electrical digital data processing, computer-aided design, and special data processing applications.

Inactive Publication Date: 2018-06-05
AVIC SAC COMML AIRCRAFT
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  • Claims
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Problems solved by technology

[0004] According to the Composite Materials Handbook (formerly the U.S. Army Standard), the research on the determination method of accidental damage detection interval of commercial aircraft composite structure in foreign countries is earlier, and the semi-probability simplified method is also applied in the certification of some foreign models of composite structure, but this method Assuming that the detection probability is 1.0, the design is too conservative and reduces the economy of the aircraft
Due to the late start of the application of composite materials in domestic commercial aircraft, a method for determining the inspection interval of composite structures that can obtain airworthiness certification has not been developed.

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  • Probability theory based airplane composite structure detection interval determination method
  • Probability theory based airplane composite structure detection interval determination method
  • Probability theory based airplane composite structure detection interval determination method

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Embodiment Construction

[0042] The specific implementation process of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0043] Order P at Indicates the impact threat probability of the structure in a single flight (or unit flight hour); P rat Indicates the probability that the structural load is greater than the remaining strength of the structure after damage; P dat Indicates the detection probability of structural damage, and it is necessary to count the P of various detection methods for the structure separatelydat curve. In order to ensure the service safety of the structure, the following formula must be satisfied during the detection period of the structure:

[0044] P rat ×P at ×(1-P dat )≤10 -9 / fh

[0045] Obviously, where P at ×(1-P dat ) represents the probability of the occurrence of the event “the undetected accidental impact damage reduces the structural strength to the K×LL load level”. Its specific implementation process...

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Abstract

The invention provides a probability theory based airplane composite structure detection interval determination method. Conditions needed to be met include that a load has a 'K.LL' level, and loweringstructural strength to the 'K.LL' load level due to undetected accidental impact damages is impossible, wherein a formula for calculation of the conditions is that probability load (K*LL)*probabilityundetected damages (K*LL) is smaller than or equal to 10<-9>/fh. The method fills a gap of a domestic commercial airplane composite structure detection interval determination method, structural completeness in a whole service life is guaranteed, the structural accidental damage inspection interval determination method is researched comprehensively according to a probability analysis method on thepremise of guarantee of safety and reliability, and the scientific, complete and systematic detection interval determination method is formed finally.

Description

technical field [0001] The invention relates to a method for determining the inspection interval of an aircraft composite material structure based on probability theory. Background technique [0002] In the field of civil aviation design, based on the characteristics of economy and safety, the requirement of compliance certification: the failure of the aircraft structure containing damage is extremely impossible, so as to ensure the safety level of airworthiness requirements. Timely inspection of accidental damage with high probability is an important content of civil aircraft certification and continuous airworthiness, and at the same time, it is also the key to ensure the safety of the aircraft throughout its service life. Therefore, an inspection program for composite structures, including inspection intervals, scope and methods, should be developed and included in the maintenance plan. For aircraft metal structures, the determination of the detection interval should ens...

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G06F17/50
CPCG06F30/15G06F30/20G06F2113/28
Inventor 郑双贾大炜支晗刘可佳朱照泽柴宝
Owner AVIC SAC COMML AIRCRAFT
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