Research on Dynamic Characteristics of Bladed Disk System by Fixed Interface Prestressed-Free Interface CMS Super-Element Method

2015 ◽  
Vol 724 ◽  
pp. 218-221
Author(s):  
Liang Zhang ◽  
Xin Li ◽  
Tie Jian Liu
Keyword(s):  
Dynamic Characteristics ◽  
Complex Structure ◽  
Maximum Relative Error ◽  
Disk System ◽  
Free Interface ◽  
Bladed Disk ◽  
Substructure Analysis ◽  
Characteristics Analysis ◽  
Fixed Interface ◽  
Element Method

For the prestressed substructure analysis, the existing CMS super-element methods are only suitable for the model that relatively simple structure, less meshing and small number of nodes. Since the complex structure and more mesh division of an arbitrary large model such as a mistuned bladed disk system, it is more time-consuming for the dynamic characteristics analysis. Because of above shortcoming, an approximate analysis method is presented, it is called fixed interface prestressed-free interface CMS super-element method. The accuracy of this method is predicted by the example. The results showed that the dimensionless dynamic frequency maximum relative error of system is 3.072215%, which can be to meet the requirement of accuracy.

A Method of the Dynamic Analysis of Pipeline Systems Considering the Effects of Casing

2004 ◽  
Author(s):  
Lin Li ◽  
Jun Sheng
Keyword(s):  
Structural Design ◽  
Complex Structure ◽  
Pipeline System ◽  
Rigid Surface ◽  
Free Interface ◽  
Modal Synthesis ◽  
Aero Engine ◽  
Pipeline Systems ◽  
Fixed Interface ◽  
Whole Systems

The paper deals with a new method called ‘mixed interface direct component modal synthesis’ to determine the modal parameters of a large and complex structure, such as outer casing-pipeline systems of aero-engine. In this method, the whole structure is divided into several parts. The interface of the main substructure (large and complex component) is considered as a free-interface, and that of the other branch substructures are considered as fixed-interfaces. The computation of each substructure is entirely independent. Especially this method simplifies the optimization of structural design. For case-pipeline systems for example, the changes of the location of the pipe’s support will have no influence on the casing model. Hence reduplicate computation is no longer needed. The analysis of pipeline systems using fixed-interface is just the same as the usual analysis, which clamps all of the interface DOFs on a rigid surface. Two examples, a cantilever beam and a simulative case-pipeline system, are considered. Both of them also are analyzed as whole systems in ANSYS, a widely used FEM software. The numerical results obtained by this method and by ANSYS are compared, and they are identical.

scholarly journals Mobile Interface CMS Method for Vibration Characteristics Prediction of Mistuned Bladed Disk with Different Coupling Degrees

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Liang Zhang ◽  
Qidi Wang ◽  
Xin Li
Keyword(s):  
Prediction Accuracy ◽  
Direct Method ◽  
Vibration Characteristics ◽  
Vibration Modes ◽  
Disk System ◽  
Bladed Disk ◽  
Mobile Interface ◽  
Fem Method ◽  
Fixed Interface ◽  
Dynamic Frequency

The prediction of vibration characteristics was studied in the mistuned bladed disk by the mobile interface prestressed component mode synthesis (CMS) superelement method. When the strongly, generally, and weakly coupling in the mistuned bladed disk, according to the results of the direct FEM method, the prediction accuracy of this method was verified and compared with the fixed-interface CMS method by using the relative error of dynamic frequency, vibration mode matching function, and dimensionless root mean square error of vibration amplitudes. It is pointed that for mistuned bladed disk in the strong coupling, the prediction accuracy of dynamic frequency and vibration amplitudes are higher by the mobile interface CMS method and the vibration modes are matched with the direct method. In weak coupling, the results of dynamic frequency and vibration modes predicted by the mobile interface CMS method and the fixed-interface CMS method are consistent with the direct method, but the vibration amplitudes’ prediction error of the mobile interface CMS method is lower than that of the fixed-interface CMS method. In general coupling, the mobile interface CMS method has higher dynamic frequency prediction accuracy at low order, and the two methods have comparable dynamic frequency prediction accuracy at high order. The vibration modes predicted by the two methods are matched with the direct FEM method, and the prediction accuracy of vibration amplitude by the mobile interface CMS method is better than that of the fixed-interface CMS method. The results indicate that the mobile interface CMS method could more accurately predict vibration characteristics of the mistuned bladed disk with different coupling degrees and could be an effective measurement for studying the vibration characteristics of the mistuned bladed disk system.

scholarly journals DYNAMIC CHARACTERISTICS ANALYSIS OF BLADED DISK TURBOMACHINES BASED ON INTENTIONAL MISTUNING

2020 ◽  
pp. 61-70
Author(s):  
Oleg Repetckii ◽  
◽  
Van Vinh Nguyen ◽  
Keyword(s):  
Dynamic Characteristics ◽  
High Reliability ◽  
Forced Response ◽  
Rotor Blades ◽  
Design Stage ◽  
Bladed Disk ◽  
Rotor Design ◽  
Urgent Task ◽  
Characteristics Analysis ◽  
Engine Excitation

To increase technical level of energy turbomachine in modern turbomachinery, high reliability and durability of structures are required in the design, manufacture and operation of turbomachine. Any change geometry, mass, material properties of the bladed disk of turbomachine in the design is called mistuning parameters. With a small value of mistuning blades can significantly increase amplitude, displacement or stresses of the blades structures. So, analysis influence of the effect mistuning parameters on the dynamic characteristics in the field of turbomachine is an important and urgent task. This article analyzes the effect intentional mistuning of the axial bladed disk turbomachine in order to reduce forced response due to low-order engine excitation. The maximum value forced response of rotor blades turbomachine with mistuning parameters is usually much more than that of the tuned rotors. An increase level mistuning of this critical value actually leads to a decrease magnifications of the forced response. Thus, the actual work has been introducing some degree of intentional mistuning in the design to achieve these purposes. In this paper, we study the effectiveness of intentional mistuning at the design stage bladed disk turbomachine, which is introduced into the rotor design by changing the nominal mass of the blades in harmonic Формаls.

scholarly journals Dynamic Characteristics Analysis of Stepping Motor for Wristwatch Using 3-D Finite Element Method

2002 ◽  
Vol 122 (2) ◽  
pp. 144-149 ◽  
Author(s):  
Tadashi Yamaguchi ◽  
Yoshihiro Kawase ◽  
Masataka Torizawa ◽  
Hirokazu Sekino ◽  
Kinya Matsuzawa
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Dynamic Characteristics ◽  
Stepping Motor ◽  
Characteristics Analysis ◽  
Dynamic Characteristics Analysis ◽  
Element Method

scholarly journals Study on the Coupled Vibration Characteristics of a Two-Stage Bladed Disk Rotor System

2021 ◽  
Vol 11 (18) ◽  
pp. 8600
Author(s):  
Yinxin Yu ◽  
Xiaolong Jin ◽  
Yanming Fu ◽  
Tianyu Zhao
Keyword(s):  
Rotor System ◽  
The Finite Element Method ◽  
Coupled Vibration ◽  
Coupled Modes ◽  
Two Stage ◽  
Second Stage ◽  
Bladed Disk ◽  
Modal Synthesis ◽  
Fixed Interface ◽  
Element Method

This paper conducts a coupled vibration analysis of a two-stage bladed disk rotor system. According to the finite element method, the bladed disk rotor system is established. The substructure modal synthesis super-element method (SMSM) with a fixed interface and free interface is presented to obtain the vibration behaviors of the rotor system. Then, the free vibration results are compared with the ones calculated by the cyclic symmetry analysis method to validate the analysis in this paper. The results show that the modes of the two-stage bladed disk not only include the modes of the first- and second-stage bladed disk, but also the coupled modes of the two-stage bladed disk.

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