Study Of Structural Reliability Anlysis Method Based On Coupling Failure Multiple Response Surface

With the rapid development of the machinery industry, the complexity of structure and the design requirements get more and more higher, the reliability of structure become more and more attention, and the structural reliability analysis method has been a topic in the field of reliability. Most of existing methods are used to analyze structural single failure mode reliability, and published literature and research results are quite few on structural reliability analysis of muti-failure mode under the multi-field coupling interaction. For the above problems, aeroengine turbine as the study object, considering the randomness of variables, the mathematical analysis model of structural reliability analysis for multi-field coupling effect is established based on Response Surface Method(RSM) and Extremum Response Surface Method(ERSM).(1) To study the dymatic reliability analysis of structure under the conditions of coupling field, coupling failure ERSM is proposed on the basis of ERSM. Aeroengine blisk is taken as the research object, the reliability analysis and the sensitivity analysis of blisk fatigue life are respectively compelted by considering thermal-solid, the reliability degree and the sensitivity of random variables impacting the fatigue life were gained.(2) Coupling failure Dual Extremum Response Surface Method(DERSM) is proposed on the foundation of coupling failure ERSM and is used to solve the problem of dynamic linkage reliability analysis of structure when dual failure modes coexistence.(3) To study the influence of multi-discipline multi-object on the performance of structural accurately, coupling failure Multiple Response Surface Method(MRSM) is proposed and is applied to analyze the multi-subject and multi-object comprehensive reliability of aeroengine turbine blisk under considering fluid-thermal-solid coupling interaction.(4) A dynamic reliability analysis method-coupling failure Multiple Extremum Response Surface Method(MERSM)-is proposed and is used to deal with the problem of the coexistence of multi-failure mode in the condition of two-way fluid-thermal-solid coupling based on the theory of coupling failure ERSM.The comprehensive reliability and sensitivity analysis of the turbine blisk was used to validate the MERSM.(5) For the problem of multi-component and multi-failure mode analysis, the application of MERSM is further studied. Aeroengine turbine blade-disk as an example, considering thermal-structure coupling interaction, the dynamic reliability analysis and sensitivity analysis are carried out by using MERSM.