Purpose

This paper aims to deal with the problem of vibration in an aircraft engine turbine shaft shield. The physical model of the system under study is inspired by the PZL-10W aviation jet engine shaft shield and is a structure of the profile circular arc. The main goal of the presented research is to develop a modal model of the discussed object. Another task is to determine the impact of the shaft shield damage on the change of dynamic parameters (the values of the natural frequencies and changing of the shape of the corresponding natural forms) of the discussed object. Finally, the task is connected with the calculation of the excitation speeds of the discussed shaft shield’s respective natural frequencies.

Design/methodology/approach

To realize the main goal finite element method simulation and experimental investigation were conducted. The quality of the achieved models is determined based on the relative error of natural frequencies and the similarity to normal modes established on the basis of the modal assurance criterion (MAC) indicator. The Campbell diagram was used to calculate the excitation speeds of the discussed shaft shield’s respective natural frequencies.

Findings

The obtained results indicate the changes in the dynamic properties of the shaft shield as a result of its cracking. On the basis of the adopted measurement (MAC indicator), the level of similarity was established between the numerical simulation results and the measurement results for the undamaged shield. Verification of the different mode shapes using the CrossMAC tool is an effective method, which allows comparing of the shape of the natural form and may be helpful in the process of adjusting modal models to the results of experimental tests.

Practical implications

It is important to note that as a result of using commercial software (ANSYS program) and a commercial measuring system (Bruel and Kjaer), the presented analysis can be attractive for design engineers dealing with the dynamics of aviation systems.

Originality/value

The paper presents the authors’ original approach to the dynamic analysis of the aviation engine turbine shaft shield, which can be useful for engineers dealing with the issue of vibration in shaft shield systems.

中文翻译：

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航空发动机涡轮轴罩的振动分析

目的

本文旨在解决飞机发动机涡轮轴护罩中的振动问题。所研究系统的物理模型受PZL-10W航空喷气发动机轴罩的启发，是轮廓圆弧的结构。提出的研究的主要目的是发展所讨论对象的模态模型。另一个任务是确定轴罩损坏对所讨论对象的动态参数（自然频率值和相应自然形式的形状变化）的变化的影响。最后，该任务与所讨论的轴罩的各个固有频率的激励速度的计算有关。

设计/方法/方法

为了实现主要目标，进行了有限元方法的仿真和实验研究。所获得模型的质量是基于固有频率的相对误差以及与基于模态保证标准（MAC）指标建立的正常模式的相似性来确定的。使用坎贝尔图来计算所讨论的轴罩各自固有频率的激励速度。

发现

所获得的结果表明，由于开裂，轴护罩的动态特性发生了变化。基于所采用的测量（MAC指标），在数值模拟结果与未损坏屏蔽的测量结果之间建立了相似度。使用CrossMAC工具验证不同模式的形状是一种有效的方法，它可以比较自然形式的形状，并且在将模态模型调整为实验测试结果的过程中可能会有所帮助。

实际影响

重要的是要注意，由于使用了商业软件（ANSYS程序）和商业测量系统（Bruel和Kjaer），因此所提出的分析对于处理航空系统动力学的设计工程师而言可能是有吸引力的。

创意/价值

本文介绍了作者对航空发动机涡轮轴护罩进行动力学分析的原始方法，这对于处理轴护罩系统中的振动问题的工程师很有用。