Campbell¶

class +AMrotorSIM.+Experiments.@Campbell.Campbell(rotorsystem)¶

Bases: handle

Class for campbell diagram

See also AMrotorSIM.Graphs.Campbell

name = "'Campell Analysis'"¶: (Access = private)

omega = None¶: angular velocity

num = None¶: struct which will gather all kind of numbers

EVf = None¶: eigenvectors forward

EVb = None¶: eigenvectors backward

EWf = None¶: eigenvalues forward

EWb = None¶: eigenvalues backward

Campbell(rotorsystem)¶

Constructor

Parameters: rotorsystem (struct) – Object of class Rotorsystem
Returns: Campbell object

set_up(omega, nModes)¶

Defines necessary parameters for campbell analysis

Parameters

omega (vector) – Range of the angular velocity [1/min])
nModes (double) – Number of desired eigenmodes

Returns

Added parameters in Campbell object

calculate()¶: Carries out the calculation

get_number_of_eigenvalues()¶

Collects the number of eigenvalues

Returns: Adds numbers to num-struct

get_number_of_modes()¶

Collects the number of eigenmodes

Returns: Number of modes

get_eigenvalues()¶

Extracts the eigenvalues

Returns: Eigenvalues (EW) divided in forward and backward EV

get_omega()¶

Extracts omega

Returns: Angular velocity (omega)

set_number_of_revolutions()¶

(private) Sets angular velocity in num-struct

Returns: Angular velocity in num-struct

set_number_of_modes(nModes)¶

(private) Makes the amount of modes even, if thats not the case

Parameters: nModes (double) – Number of desired eigenmodes
Returns: Even amount of modes in num-struct

+AMrotorSIM.+Experiments.@Campbell.get_position_entries(obj, V)¶

Extracts the elements of the eigenvector matrix referring to the position

Parameters: V (matrix) – Eigenvectors columnwise
Returns: Eigenvectormatrix with only position entries

+AMrotorSIM.+Experiments.@Campbell.get_separation_eigenvectors(obj, EV_raw, EW_raw)¶

Extracts eigenvalues (EW, eigenwert) and corresponding eigenvectors (EV) for forward, backward or no whirl from raw data

Parameters

EV_raw (matrix) – Eigenvector
EW_raw (complex double) – Eigenvalue (eigenwert)

Returns

EV’s and EW’s of forward, backward or no whirl (EV_for,EW_for,EV_back,EW_back,EV_0,EW_0) and phase information (Phase_xy, Phase_xy_mean)

+AMrotorSIM.+Experiments.@Campbell.get_state_space_matrices(obj, omega)¶

Builds state space matrices of form A=[M, 0;0, K] and B=[omega*G+C, K;K, 0]

Parameters: omega (double) – Angular velocity
Returns: State space matrices A, B

+AMrotorSIM.+Experiments.@Campbell.perform_eigenanalysis(obj, mat)¶

Performs the eigenanalysis

Parameters: mat (struct) – Struct with ss-matrices in form mat.A and mat.B from function get_state_space_matrices
Returns: Eigenvector (V) and eigenvalue (D) matrices

+AMrotorSIM.+Experiments.@Campbell.private.get_positive_entries(Vin, Din)¶

Extracts only the positive enries of V and D

Parameters

Vin (matrix) – Eigenvectormatrix raw
Din (matrix) – Eigenvaluematrix (diagonal) raw

Returns

V and D with only positive entries