Study On The Vibration Response Of The Integral Blade Disk Due To Blade Mass Detunin

Integral blade disk structure is a key component of turbine rotor system.It is widely used in engineering field and has the characteristics of cyclic symmetry.In the actual working process of the blisk,due to the processing error of the manufacturer,inevitable material defects,wear caused by high-strength use,etc.,the parameters such as blade quality,stiffness and geometry in the blisk structure change,and its inherent cyclic symmetry is destroyed.In the study of vibration response characteristics of blisk,this small change is usually called detuning.The detuning will cause the vibration localization of the integral bladed disk and lead to major engineering accidents.Therefore,the research on the vibration characteristics of the detuning integral bladed disk is of great significance.Aiming at the problems of blade mass detuning and vibration localization caused by uneven blade mass distribution in the integral blade disk,the vibration response characteristics of the detuning integral blade disk are studied in this thesis.This thesis mainly analyzes the vibration response characteristics of the integral disc under the condition of detuning,and the influence of blade mass detuning on the vibration response of the integral disc under different disc parameters.Firstly,the response characteristics of the integral blade disk of the cyclic symmetrical structure are analyzed.Based on the basic principle of forced vibration response and natural characteristics of blisk,the geometric and physical model is established by using the lumped parameter method,the corresponding relationship between frequency and amplitude of Blisk is solved,and the response characteristic curve of the system is fitted.According to the variation characteristics of its response curve,the vibration response characteristics and laws of harmonic integral bladed disk system are analyzed and summarized.Secondly,the response characteristics of blade mass detuning blisk are analyzed,and the vibration response law of Blisk under the condition of blade mass detuning is studied.Based on the system motion equation established by the study of harmonic structure integral bladed disk,the response characteristic equation of blade mass detuning integral bladed disk system is derived by detuning perturbation method.Using MATLAB software to calculate and solve the equation,fit the response characteristic curve of the detuning system,and analyze the vibration response characteristics of the integral blade disk under the condition of blade mass detuning.Thirdly,the response characteristics of the detuning system under different blade disk parameters are analyzed.On the basis of blade mass detuning,take different parameters of the integral blade disk(coupling strength,damping ratio,etc.)and substitute them into the response characteristic equation for solution.Use matlab to process the relevant data and synthesize the response characteristic curve.Observe the variation characteristics of the curve,and summarize the influence law of various parameters of the blade disk on the vibration characteristics of the blade mass detuning system.Finally,the three-dimensional finite element software ANSYS is used to analyze the response characteristics of the blade mass detuning integral blade disk,and verify the accuracy of its law.The three-dimensional model of the blisk is established by using Solid Works software.The mass detuning of the blisk system is realized by changing the blade geometry.The model is imported into ANSYS Workbench for harmonic response analysis.The results are compared with those obtained by centralized parameter analysis.