Response and stability analysis of a two-spool aero-engine rotor system undergoing multi-disk rub-impact

2021 ◽  
pp. 106861
Author(s):  
Prabith K. ◽  
I.R Praveen Krishna
Keyword(s):  
Stability Analysis ◽  
Rotor System ◽  
Aero Engine ◽  
Engine Rotor

Multi Objective Optimisation of an Aero Engine Rotor System Using Nondominated Sorting Genetic Algorithm (NSGA)

2017 ◽  
Author(s):  
Joseph Shibu Kalloor ◽  
Ch. Kanna Babu ◽  
Girish K. Degaonkar ◽  
K. Shankar
Keyword(s):  
Genetic Algorithm ◽  
Critical Speed ◽  
Rotor System ◽  
Pareto Optimal ◽  
Multi Objective ◽  
Rayleigh Beam ◽  
Unbalance Response ◽  
Aero Engine ◽  
Nondominated Sorting ◽  
Engine Rotor

A comprehensive multi-objective optimisation methodology is presented and applied to a practical aero engine rotor system. A variant of Nondominated Sorting Genetic Algorithm (NSGA) is employed to simultaneously minimise the weight and unbalance response of the rotor system with restriction imposed on critical speed. Rayleigh beam is used in Finite Element Method (FEM) implemented in-house developed MATLAB code for analysis. The results of practical interest are achieved through bearing-pedestal model and eigenvalue based Rayleigh damping model. Pareto optimal solutions generated and best solution selected with the help of response surface approximation of the Pareto optimal front. The outcome of the paper is a minimum weight and minimum unbalance response rotor system which satisfied the critical speed constraints.

Modelling of Misaligned Rotor System in Aero-Engines and Interval Method Investigation

2013 ◽  
Author(s):  
Guihua Wang ◽  
Yanhong Ma ◽  
Tianrang Li ◽  
Jun Li ◽  
Jie Hong
Keyword(s):  
Dynamic Response ◽  
Rotor System ◽  
Mechanical Parameters ◽  
Lagrange Method ◽  
Interval Method ◽  
Aero Engine ◽  
Mechanical Factors ◽  
Aero Engines ◽  
Rotor Model ◽  
Engine Rotor

Based on the structural and dynamic characteristics of aero-engine rotor system, we used Lagrange method to develop a two-bearing and a multi-bearing rotor model with misalignment. An equation of motion was derived with features of response examined. Due to the uncertainty of mechanical parameters, interval method was adopted to investigate the dynamic response of rotor system with misalignment. Dynamic response and influence of the key mechanical parameters will be obtained in further research. The two times harmonic was found as a distinctive feature of misalignment and the magnitude of it in spectrum is closely related to some key mechanical factors. We also found interval method outstandingly performed in investigating dynamic response when some key parameters are uncertain.

Bending Stiffness and Dynamic Characteristics of a Rotor With Spline Joints

2013 ◽  
Author(s):  
Fayong Wu ◽  
Zhichao Liang ◽  
Yanhong Ma ◽  
Dayi Zhang
Keyword(s):  
Dynamic Characteristics ◽  
Natural Frequencies ◽  
Bending Stiffness ◽  
Rotor System ◽  
Contact State ◽  
Structural Discontinuity ◽  
Aero Engine ◽  
Stiffness Characteristics ◽  
Stiffness Distribution ◽  
Engine Rotor

Spline is a kind of typical joint structures widely used in the aero-engine rotor system. The stiffness distribution of the spool is affected by the spline joint’s stiffness directly. Therefore, it is significant to investigate the spline joint’s stiffness characteristics and its influences on the dynamic characteristics of the rotor system. To figure out the factors that affect the bending stiffness of the spline joint, a mechanical model which takes contact state into account was built based on the structure analysis and force state analysis. In addition, an actual rotor with a spline joint was established to measure the stiffness under different loads, and the results were compared with the analysis by three modeling methods. Furthermore, the natural frequencies of the rotor were tested. Obtained results indicate that the structural discontinuity, the surface stiffness and the clearance fit cause the loss of local angular stiffness and linear stiffness. Meanwhile, the stiffness of the rotor with the spline joint is weaker along with the increase of the load/deformation, and become stable when undergoing the huge load/deformation. Besides, the local blending stiffness is presented as nonlinear and uncertainty subjected to an interval, which further affected the dynamic characteristics of rotor system.

Studies on dynamic characteristics of the joint in the aero-engine rotor system

2012 ◽  
Vol 29 ◽  
pp. 120-136 ◽  
Author(s):  
Liu Shuguo ◽  
Ma Yanhong ◽  
Zhang Dayi ◽  
Hong Jie
Keyword(s):  
Dynamic Characteristics ◽  
Rotor System ◽  
Aero Engine ◽  
Engine Rotor

scholarly journals Dynamic Responses of the Aero-Engine Rotor System to Bird Strike on Fan Blades at Different Rotational Speeds

2021 ◽  
Vol 11 (19) ◽  
pp. 8883
Author(s):  
Bin Wu ◽  
Jiewei Lin ◽  
Reza Hedayati ◽  
Guichang Zhang ◽  
Junhong Zhang ◽  
...  
Keyword(s):  
Periodic Motion ◽  
Impact Force ◽  
Rotor System ◽  
Dynamic Responses ◽  
Dynamic Equations ◽  
Bird Strike ◽  
Ct Scanner ◽  
Aero Engine ◽  
The Impact ◽  
Engine Rotor

To study the effect of a bird striking engine fan on the rotor system, a low-pressure rotor system dynamic model based on a real aero-engine structure was established. Dynamic equations were derived considering the case of the bird strike force which transferred to the rotor system. The bird strike force was obtained from the bird strike process simulation in LS-DYNA, where a smoothed particle hydrodynamics (SPH) mallard model was constructed using a computed tomography (CT) scanner, and finite element method (FEM) was used to simulate the bird strike on an actual fan model. The dynamic equations were solved using the Newmark-β method. The effect of rotational speeds on the rotor system dynamics after bird strike was investigated and discussed. Results show that the maximum bird impact force can reach 104 kN at 3772 r/min. Impact time is only 0.06 s, but the bird strike on fan blades lead to a transient shock on the rotor system. Under the action of transient shocks, the rotor system displacement in the horizontal and vertical directions increase sharply, and the closer the mass point is to the fan, the more it is affected; the vibration amplitude at the fan will increase 15 times within 0.1 s of the bird strike and will gradually decrease with the effect of damping. The dynamics of the rotor system changes from a stable single periodic motion to a complex irregular quasi-periodic motion after a bird strike, and the strike force excites the first-order vibrational mode of the rotor system. This phenomenon occurs at all speeds when bird strikes occur. Bird strikes will cause resonance in the rotor system, which may cause damage to the engine. It was also seen that the bird strike force, and hence the effects on the rotor system, increases as the engine rotational speed increases; the peak force is larger and the number of peaks has increased. The impact force at 3772 r/min is 99.5 kN higher than at 836 r/min, and three additional peaks emerged. This effect is more reflected in the amplitude, and the overall vibration characteristics do not change. Combining the bird strike with the rotor dynamics calculation, the dynamic response of the aero-engine rotor system to bird strike is studied at different flight stages, which is of guiding significance for power evaluation of aero engines after bird strike.

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