Maximum Bladed Disk Forced Response From Distortion of a Structural Mode

2002 ◽  
Author(s):  
J. A. Kenyon ◽  
J. H. Griffin ◽  
D. M. Feiner
Keyword(s):  
Forced Response ◽  
Maximum Response ◽  
Strong Response ◽  
Bladed Disk ◽  
System A ◽  
Random Mistuning ◽  
Harmonic Components ◽  
Structural Mode

A method is presented for obtaining maximum bladed disk forced response from distortion of a structural mode. It is shown that maximum response from mode distortion in a bladed disk occurs when the harmonic components of a distorted mode superimpose in a certain manner, causing localization of the mode and strong response in a particular blade. In addition, it is shown that the response of an intentionally mistuned system with maximum response does not change significantly when small random mistuning is added to the system. A method is described for calculating the structural mistuning necessary to obtain the distorted mode that gives maximum response. The theory is validated numerically.

Maximum Bladed Disk Forced Response From Distortion of a Structural Mode

2003 ◽  
Vol 125 (2) ◽  
pp. 352-363 ◽  
Author(s):  
J. A. Kenyon ◽  
J. H. Griffin ◽  
D. M. Feiner
Keyword(s):  
Forced Response ◽  
Maximum Response ◽  
Strong Response ◽  
Bladed Disk ◽  
System A ◽  
Random Mistuning ◽  
Harmonic Components ◽  
Structural Mode

A method is presented for obtaining maximum bladed disk forced response from distortion of a structural mode. It is shown that maximum response from mode distortion in a bladed disk occurs when the harmonic components of a distorted mode superimpose in a certain manner, causing localization of the mode and strong response in a particular blade. In addition, it is shown that the response of an intentionally mistuned system with maximum response does not change significantly when small random mistuning is added to the system. A method is described for calculating the structural mistuning necessary to obtain the distorted mode that gives maximum response. The theory is validated numerically.

Experimental Demonstration of Maximum Mistuned Bladed Disk Forced Response

2003 ◽  
Vol 125 (4) ◽  
pp. 673-681 ◽  
Author(s):  
J. A. Kenyon ◽  
J. H. Griffin
Keyword(s):  
Traveling Wave ◽  
Close Agreement ◽  
Maximum Amplitude ◽  
Forced Response ◽  
Maximum Response ◽  
Experimental Demonstration ◽  
Wave Excitation ◽  
Bladed Disk ◽  
Engine Order ◽  
Structural Mode

A theory was previously developed for predicting robust maximum forced response in mistuned bladed disks from distortion of a structural mode. This paper describes an experiment to demonstrate the theory. A bladed disk is designed to be sufficiently sensitive to mistuning to obtain maximum response. The maximum amplitude magnification from mistuning is predicted using the theory, 1.918. The bladed disk is intentionally mistuned to obtain the maximum response, and the response to an engine order traveling wave excitation is measured. The measured amplitude magnification is in close agreement with the theory. The robustness of the maximum response is demonstrated.

Experimental Demonstration of Maximum Mistuned Bladed Disk Forced Response

2003 ◽  
Author(s):  
J. A. Kenyon ◽  
J. H. Griffin
Keyword(s):  
Traveling Wave ◽  
Close Agreement ◽  
Maximum Amplitude ◽  
Forced Response ◽  
Maximum Response ◽  
Experimental Demonstration ◽  
Wave Excitation ◽  
Bladed Disk ◽  
Engine Order ◽  
Structural Mode

A theory was previously developed for predicting robust maximum forced response in mistuned bladed disks from distortion of a structural mode. This paper describes an experiment to demonstrate the theory. A bladed disk is designed to be sufficiently sensitive to mistuning to obtain maximum response. The maximum amplitude magnification from mistuning is predicted using the theory, 1.918. The bladed disk is intentionally mistuned to obtain the maximum response, and the response to an engine order traveling wave excitation is measured. The measured amplitude magnification is in close agreement with the theory. The robustness of the maximum response is demonstrated.

scholarly journals Vibrational Response Analysis of Mistuned Bladed Disk System of Grouped Blades

1998 ◽  
Author(s):  
Y. Kaneko ◽  
K. Mori ◽  
H. Ohyama ◽  
E. Watanabe
Keyword(s):  
Synthesis Method ◽  
Forced Response ◽  
Response Analysis ◽  
Analysis Method ◽  
Disk System ◽  
Vibrational Response ◽  
Bladed Disk ◽  
System A ◽  
Vibrational Characteristics ◽  
Grouped Blades

For the purpose of the efficient analysis of a mistuned bladed disk system, a new analysis method which applies the substructure synthesis method and the modal analysis method is proposed. Using the proposed method, the vibrational characteristics of the grouped blades structure are studied. From the results, it is found that the grouped blades structure is very sensitive to the mistuning. It is also found that the mixed grouped blades structure (a bladed disk system consisting of some different types of grouped blades relating to the number of blades contained) has an undesirable effect on the forced response. Moreover, by comparing the vibrational characteristics of the integral shroud blades (ISB) structure with those of the grouped blades structure, it is clarified that the reliability of the ISB structure is superior to other structures also from the viewpoint of the mistuning.

Theoretical Study of the Vibration Suppression on a Mistuned Bladed Disk Using a Bi-periodic Piezoelectric Network

2018 ◽  
Vol 35 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Lin Li ◽  
Pengcheng Deng ◽  
Jiuzhou Liu ◽  
Chao Li
Keyword(s):  
Vibration Suppression ◽  
Robustness Analysis ◽  
Forced Response ◽  
Lumped Parameter Model ◽  
Modal Assurance Criterion ◽  
Vibration Localization ◽  
Bladed Disk ◽  
Lumped Parameter ◽  
Random Mistuning ◽  
Response Amplification

AbstractThe paper deals with the vibration suppression of a bladed disk with a piezoelectric network. The piezoelectric network has a different period (so called bi-period) from that of the bladed disk and there is no inductor in it. The system is simulated by an electromechanical lumped parameter model with two DOFs per sector. The research focuses on suppressing the amplitude magnification or reducing the vibration localization of the mistuned bladed disk. The dynamic equations of the system are derived. Both mechanical mistuning and electrical mistuning have been taken into account. The Modified Modal Assurance Criterion (MMAC) is used to evaluate the vibration suppression ability of the bi-periodic piezoelectric network. The Monte Carlo simulation is used to calculate the MMAC of the system with the random mistuning. As a reference, the forced responses of the bladed disk with and without the piezoelectric network are given. The results show that the piezoelectric network would effectively suppress amplitude magnification induced by mistuning. The vibration amplitude is even smaller than that of the tuned system. The robustness analysis shows that the bi-periodic piezoelectric network can provide a reliable assurance for avoiding the forced response amplification of the mistuned bladed disk. The amplified response induced by the mechanical mistuning with standard deviation 0.2 can be effectively suppressed through the bi-periodic piezoelectric network.

On the Individual and Combined Effects of Intentional Mistuning, Coupling and Damping on the Forced Response of Bladed Disks

2008 ◽  
Author(s):  
Changbo Yu ◽  
Jianjun Wang ◽  
Qihan Li
Keyword(s):  
High Cycle Fatigue ◽  
Numerical Study ◽  
Threshold Value ◽  
Forced Response ◽  
Combined Effects ◽  
Bladed Disks ◽  
Disk Model ◽  
Bladed Disk ◽  
Random Mistuning ◽  
The Individual

Random mistuning always exists in bladed disk structures. The maximum blade forced response amplitudes are often much larger than those of their perfectly tuned counterparts, which leads to eventual failure via high cycle fatigue (HCF). Therefore, it is of great importance to predict and, ultimately, to reduce the blade forced response levels as a result of random mistuning. In this paper, intentional mistuning is introduced into a simplified 12-bladed disk model by varying the stiffness of the blades in periodic harmonic patterns. The individual and combined effects of intentional mistuning, coupling and damping are examined in the absence and presence of random mistuning through numerical study. It is found that there is some threshold value of intentional mistuning and coupling that leads to maximum mistuning effects and certain relations among intentional mistuning strength, integer harmonics, coupling and damping can suppress the response levels of mistuned bladed disks, which provides useful guidelines for safe and reliable designs of bladed disk systems.

On Damping Entire Bladed Disks Through Dampers on Only a Few Blades

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
Javier Avalos ◽  
Marc P. Mignolet
Keyword(s):  
Optimum Design ◽  
Forced Response ◽  
Reduced Order Model ◽  
Order Model ◽  
Bladed Disks ◽  
Single Degree Of Freedom ◽  
Reduced Order ◽  
Bladed Disk ◽  
Single Degree ◽  
Random Mistuning

The focus of this paper is on demonstrating the potential to damp entire bladed disks using dampers on only a fraction of the blades. This problem is first considered without the presence of random mistuning, and it is demonstrated that a few dampers at optimized locations can lead to a significant reduction in the forced response of the entire bladed disk. Unfortunately, this optimum design may not be robust with respect to random mistuning and a notable fraction of the reduction in forced response obtained may disappear because of mistuning. To regain the reduction in forced response but with mistuning present, robustness to mistuning is enhanced by using intentional mistuning in addition to dampers. The intentional mistuning strategy selected here is the A/B pattern mistuning in which the blades all belong to either type A or B. An optimization effort is then performed to obtain the best combination of A/B pattern and damper location to minimize the mistuned forced response of the disk. The addition of intentional mistuning in the system is shown to be very efficient, and the optimum bladed disk design does indeed exhibit a significant reduction in mistuned forced response as compared with the tuned system. These findings were obtained on both single-degree-of-freedom per blade-disk models and a reduced order model of a blisk.

On Damping Entire Bladed Disks Through Dampers on Only a Few Blades

2008 ◽  
Author(s):  
Javier Avalos ◽  
Marc P. Mignolet
Keyword(s):  
Optimum Design ◽  
Forced Response ◽  
Reduced Order Model ◽  
Order Model ◽  
Bladed Disks ◽  
Single Degree Of Freedom ◽  
Reduced Order ◽  
Bladed Disk ◽  
Single Degree ◽  
Random Mistuning

The focus of this paper is on demonstrating the potential to damp entire bladed disks using dampers on only a fraction of the blades. This problem is first considered without the presence of random mistuning and it is demonstrated that a few dampers at optimized locations can lead to a significant reduction in the forced response of the entire bladed disk. Unfortunately, this optimum design may not be robust with respect to random mistuning and a notable fraction of the reduction in forced response obtained may disappear because of mistuning. To regain the reduction in forced response but with mistuning present, robustness to mistuning is enhanced by using intentional mistuning in addition to dampers. The intentional mistuning strategy selected here is the A/B pattern mistuning in which the blades all belong to either type A or B. An optimization effort is then performed to obtain the best combination of A/B pattern and damper location to minimize the mistuned forced response of the disk. The addition of intentional mistuning in the system is shown to be very efficient and the optimum bladed disk design does indeed exhibit a significant reduction of mistuned forced response as compared to the tuned system. These findings were obtained on both single-degree-of-freedom per blade disk models and a reduced order model of a blisk.

Identification of the Maximum Responding Blade in Mistuned Bladed Disks

2003 ◽  
Author(s):  
Bing Xiao ◽  
Alejandro J. Rivas-Guerra ◽  
Marc P. Mignolet
Keyword(s):  
Experimental Testing ◽  
Forced Response ◽  
Statistical Analyses ◽  
Maximum Response ◽  
Bladed Disks ◽  
Disk Model ◽  
Bladed Disk ◽  
Two Degree Of Freedom ◽  
Full Disk

This paper focuses on the identification/prediction of the blade exhibiting the largest response in mistuned bladed disks. This information is very important in experimental/testing efforts as it permits the most effective positioning of a few gages to capture the maximum response on the disk. In computational statistical analyses, knowing the highest responding blade is also quite valuable as it may lead to computational savings in the determination of the maximum response. Different strategies are proposed here for the experimental and computational contexts. In the former situation, mistuning is typically unknown but only one or a few disks must be considered. The proposed solution is then to estimate the mistuned blade properties and to rely on this identified bladed disk model to predict the blades that are likely to exhibit the largest responses through exact, full disk solutions. On the contrary, in computational statistical analyses, mistuning is specified but a potentially large number of disks must be analyzed and it is desired to bypass the ensemble of full disk solutions. Accordingly, a novel, computationally very efficient algorithm is proposed for a preliminary estimation of the forced response of mistuned disks from which the blades that are likely to exhibit the largest responses can be predicted. Examples of application on single- and two-degree-of-freedom per blade models and a reduced order model of a blisk demonstrate the reliability of the proposed strategies.

Vibration Suppression of Mistuned Coupled-Blade-Disk Systems Using Piezoelectric Circuitry Network

2007 ◽  
Author(s):  
Hongbiao Yu ◽  
K. W. Wang
Keyword(s):  
System Analysis ◽  
Vibration Suppression ◽  
Effective Means ◽  
Forced Response ◽  
Bladed Disks ◽  
Disk Model ◽  
Vibration Localization ◽  
Bladed Disk ◽  
Random Mistuning ◽  
Blade System

In this research, piezoelectric networking is investigated as an effective means for vibration suppression of mistuned bladed disk systems. Due to mistuning (i.e., imperfections in blade properties), bladed disks in turbo-machinery often suffer from vibration localization. In such cases, the vibration energy is confined to a small number of blades and forced response can be drastically increased when the structure is under engine order force excitation. To suppress the excessive vibration caused by localization, a piezoelectric networking concept has been proposed and analyzed for a multi-blade system in a previous study by the authors [1]. This research further extends the investigation with focus on circuitry design for a complex bladed disk model with the consideration of coupled blade-disk dynamics. A new multi-circuit piezoelectric network is designed and analyzed for multiple-harmonic vibration suppression of bladed disks. An optimal network is derived analytically based on system analysis. The performance of the network for bladed disks with random mistuning is examined using Monte Carlo simulation. The effects of variations (mistuning and detuning) in circuit parameters are also studied. Finally, a method to improve system performance and robustness is discussed.

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