Crashworthiness uncertainty analysis of typical civil aircraft based on Box-Behnken method

• 作 者: Ren Yiru Xiang Jinwu
• 机 构: School of Aeronautic Science and Engineering, Beihang University,
• 出 处: Chinese Journal of Aeronautics
• 发表日期: 2014年03期
• 关键词: Box-Behnken method Civil aircraft Crashworthiness Failure behavior Uncertainty a

The crashworthiness is an important design factor of civil aircraft related with the safety of occupant during impact accident. It is a highly nonlinear transient dynamic problem and may be greatly influenced by the uncertainty factors. Crashworthiness uncertainty analysis is conducted to investigate the effects of initial conditions, structural dimensions and material properties. Simplified finite element model is built based on the geometrical model and basic physics phenomenon. Box–Behnken sampling and response surface methods are adopted to obtain gradient information.Results show that the proposed methods are effective for crashworthiness uncertainty analysis.Yield stress, frame thickness, impact velocity and angle have great influence on the failure behavior,and yield stress and frame thickness dominate the uncertainty of internal energy. Failure strain and tangent modulus have the smallest influence on the initial peak acceleration, and gradients of mean acceleration increase because the appearance of material plastic deformation and element failure.

The crashworthiness is an important design factor of civil aircraft related with the safety of occupant during impact accident. It is a highly nonlinear transient dynamic problem and may be greatly influenced by the uncertainty factors. Crashworthiness uncertainty analysis is conducted to investigate the effects of initial conditions. Structural finite and material properties. Simplified finite element model is built on the geometrical model and basic physics phenomenon. Box-Behnken sampling and response surface methods are obtained to obtain gradient information. Results show that the proposed methods are effective for crashworthiness uncertainty analysis .Yield stress, frame thickness, impact velocity and angle have great influence on the failure behavior, and yield stress and frame thickness dominate the uncertainty of internal energy. Failure strain and tangent modulus have the smallest influence on the initial peak acceleration, and gradients of mean acceleration increase because the appearance of material plastic deformation and element failure.