Life Prediction for a CMC Component Using the NASALIFE Computer Code
Life Prediction for a CMC Component Using the NASALIFE Computer Code
复制标题
使用 NASALIFE 计算机代码预测 CMC 组件的寿命
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
S. Mital
中科院分区：
文献类型：
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作者：
J. Gyekenyesi;P. Murthy;S. Mital
本文用计算机程序NASALIFE估算了SiC/SiC静叶在不同热机械载荷条件下的寿命。这项工作的主要目的是表明如何使用计算机代码NASALIFE来合理估计由先进陶瓷基复合材料（CMC）制成的实际推进系统部件的寿命。简单的加载条件提供了易于观察和可接受的寿命预测。改变载荷条件，使低周疲劳和蠕变受到独立影响，可提供不同载荷引起的寿命和蠕变引起的寿命结果的预期趋势。分析基于9/99熔融渗透SiC纤维增强SiC的理想化经验数据。1.发动机公司不断努力提高其燃气涡轮机发动机的性能和寿命。随着新材料和新概念应用于燃气轮机以提高工作温度、减轻重量并提高空气动力学效率，材料被推向了新的极限。此外，还需要减少维护成本和停机时间，使寿命预测成为设计过程中越来越重要的一部分。准确确定发动机部件在使用中的疲劳寿命的任务已经变得越来越复杂。造成这种情况的部分原因是，目前在设计过程中经常考虑复杂的任务。这些任务包括发动机关键部件所经历的多轴应力和温度的大变化。NASALIFE的目的是为设计人员提供一个方便的软件包，用于确定循环或可变热机械载荷下部件的寿命。该计划是在美国国家航空航天局（NASA）的启用推进材料（EMPs）和超高效发动机技术（UEET）计划下开发的。Brewer（1999年）总结了UEET计划及其目标，Shaw和Peddie（2004年）介绍了UEET计划概述。Gyekenyesi等人（2005年）详细介绍了NASALIFE，Levine等人（2000年）提供了简要概述。应该指出，NASALIFE不是预测部件寿命的最终和全面计划，而是改进寿命预测技术的持续过程的一部分。经验数据被用作预测构件的疲劳和断裂寿命的参考。
Abstract The computer code, NASALIFE, was used to provide estimates for life of a SiC/SiC stator vane under varying thermomechanical loading conditions. The primary intention of this effort is to show how the computer code NASALIFE can be used to provide reasonable estimates of life for practical propulsion system components made of advanced ceramic matrix composites (CMC). Simple loading conditions provided readily observable and acceptable life predictions. Varying the loading conditions such that low cycle fatigue and creep were affected independently provided expected trends in the results for life due to varying loads and life due to creep. Analysis was based on idealized empirical data for the 9/99 Melt Infiltrated SiC fiber reinforced SiC. 1. Introduction Engine companies are constantly striving to improve the performance and life of their gas turbine engines. Materials are pushed to new limits as new materials and concepts are applied to gas turbines to increase operating temperatures, reduce weight, and improve aerodynamic efficiencies. Also, there is the need to reduce maintenance costs and down time making life prediction an ever more important part of the design process. The task of accurately determining the fatigue life of an engine component in service has become increasingly complex. This results, in part, from the complex missions which are now routinely considered during the design process. These missions include large variations of multiaxial stresses and temperatures experienced by critical engine parts. NASALIFE was written in an attempt to provide a convenient software package to the designer for determining the life of a component under cyclic or variable thermo-mechanical loading. The program was developed under the National Aeronautics and Space Administration’s (NASA) Enabling Propulsion Materials (EPM) and Ultra Efficient Engine Technology (UEET) programs. The EPM program and its objectives were summarized by Brewer (1999) and the UEET program overview was presented by Shaw and Peddie (2004). NASALIFE was covered in detail by Gyekenyesi, et al. (2005) with a brief overview provided earlier by Levine, et al. (2000). It should be noted that NASALIFE is not a final and all inclusive program for predicting component life, but is the part of the continuing process to improve life prediction techniques. Empirical data is used as a reference for predicting the fatigue and rupture life of a component.