Patent ID: 11860066
Assignee: XI'AN JIAOTONG UNIVERSITY
Field: Measurement (Instruments)
Classification: CPC G  F | IPC F  G

Claim 5:
6. The method according to claim 5, wherein an nm order vibration parameter β=(Sbtt)†ubtt(t) is acquired by utilizing a circumferential Fourier fitting algorithm, wherein β=[c,A1 cos(φ1),A1 sin(φ1), . . . ,Anm cos(φnm),Anm sin(φnm)]T, Ai represents for a vibration amplitude, fi represents for a modal frequency, and φi represents for an initial phase; the superscript † represents for the inversion of the matrix; the superscript T represents for the transposition of a vector; and further, blade tip single-point multimodal vibration signals are acquired by reconstruction:, u
    btt
   
    
   (
   t
   )
  
  =
  
   
    c
    +
    
     
      ∑
      
       i
       =
       1
      
      n
     
     
      
       u
       
        btt
        ,
        i
       
      
      (
      t
      )
     
    
   
   =
   
    
     c
     +
     
      
       ∑
       
        i
        =
        1
       
       n
      
      
       
        A
        i
       
       ⁢
       
        sin
        ⁡
        (
        
         
          
           ω
           i
          
          ⁢
          t
         
         +
         
          φ
          i
         
        
        )
       
      
     
    
    =
    
     c
     +
     
      
       ∑
       
        i
        =
        1
       
       n
      
      
       
        A
        i
       
       ⁢
       cos
       ⁢
       
        (
        
         φ
         i
        
        )
       
       ⁢
       sin
       ⁢
       
        (
        
         
          ω
          i
         
         ⁢
         t
        
        )
       
      
     
     +
     
      
       A
       i
      
      ⁢
      sin
      ⁢
      
       (
       
        φ
        i
       
       )
      
      ⁢
      cos
      ⁢
      
       (
       
        
         ω
         i
        
        ⁢
        t
       
       ), wherein ubtt,i(t) represents for decoupled ith order vibration signals, c represents for static deformation of the blade, ωi represents for a circular frequency of multimodal vibration of the blade, and t represents for a vibration moment of the blade.