基于损伤等效的航空发动机加速任务试车谱编制方法

Compiling Method of Aero-Engine Acceleration Mission Test Spectrum Based on Damage Equivalence

关键词:  航空发动机  加速任务试车谱  损伤等效  低循环疲劳  蠕变  热冲击

Key words:  Aero-engine  Acceleration mission test spectrum  Damage equivalence  Low cycle fatigue  Creep  Thermal shock

摘要:

加速任务试车是发动机在地面试车台架上进行的一种缩短了试车时间、与长期寿命试车等效的试车方法，其核心是损伤等效。本文建立了一种基于损伤等效的航空发动机加速任务试车谱编制方法。对反映外场服役载荷特征的长期寿命试车谱进行统计分析，获得需要加速的小载荷循环和低功率状态等载荷信息；采用损伤等效的方法对低循环疲劳、蠕变等特征载荷进行等效加速；对加速后的载荷片段进行编排，获得加速任务试车谱。利用涡轮盘用典型高温合金材料（GH4169）的标准试样开展了长期寿命试车谱和加速任务试车谱下的损伤对比试验，试验结果表明，所编制的加速任务试车谱与长期寿命试车谱造成的结构损伤（寿命）误差为-7.61%，实现了损伤等效的目标。

Abstract:

Accelerated mission test（AMT） of aero-engine is a kind of simulated mission test conducted on ground test facility， which can reduce the test time under the premise of damage equivalence to long-term life test. The core of AMT is damage equivalence. In this paper， a compiling method of aeroengine AMT based on damage equivalence has been proposed. Firstly， the characteristic of sub-cycle and low power state which need to be accelerated， can be obtained according to long-term life test spectrum， which can reflect the characteristics of service load in outfield. Secondly， the characteristic load such as low cycle fatigue and creep can be damage equivalent accelerated based on damage accumulated model. Thirdly， the accelerated load segments will be arranged to obtain the accelerated mission test spectrum. The damage comparison experiments under the long-term life spectrum and the accelerated mission test spectrum was carried out using the standard specimens of the typical superalloy material （GH4169） for the turbine disk. The results show that， the structural damage （life） error caused by the compiled accelerated mission test spectrum and the long test spectrum is -7.61%， achieving the target of damage equivalence.