Rotordynamics forRotordynamics for®

SVSFEM s.r.o.Brno, Czech Republic

Technical support for RotordynamicsIng. László IVÁN, rotor@svsfem.cz

Rotordynamics Rotordynamics forfor ®

Rotordynamics forRotordynamics for®

“Rotordynamics for ANSYS” has been created as a problem oriented macro based tool which is integrated in ANSYS and makes it easier for the user to deal with rotor vibration problems.

The main objective of creation of the tool was to use the maximum of ANSYS capabilities like creation of finite element model, elements library, computational procedures for solution of eigenvalues, mode shapes, harmonic vibration, transition vibration.

A problem oriented user environment (UIDL) was created to make input parameters entry, specification of the analysis and results evaluation easy.

The module is fully implemented into the environment of ANSYS.

The aim of the project

Rotordynamics forRotordynamics for®

Rotordynamics Rotordynamics forfor ®

Rotordynamics forRotordynamics for®

The menu system

Rotordynamics forRotordynamics for®

Setup of Units

Ø The user can define the units by selection from a couple of predefined groupsthat he would like to use in the analysis.

Ø Based on this selection a wizard (non-binding) for input parameters entry willappear, which will shows the units in which the system expects entered values.

Rotordynamics forRotordynamics for®

BEAM4BEAM189

Rotor FE model

Ø SHAFT (Beam4, Beam189)

Ø DISC (Pipe16)

Ø SPRING-DAMPER (Combin14)

Ø MATRIX27 (Matrix27)

Ø MASS (Mass21)

PIPE16

COMBIN14

MATRIX27

MASS21

Rotordynamics forRotordynamics for®

Stiffness-damping properties for COMBIN14 elements

• Polynomial function

• TableStiffness : K(N) = K0 + K1*N + K2*N2 + K3*N3

N - rotor speed [RPM]

Rotordynamics forRotordynamics for®

Ø Static analysis for constant rotor speed

ØModal analysis

Ø Lateral – Torsional vibration

Ø Damped – Undamped analysis

ØModal analysis for variable rotor speed (Campbell diagram)

Ø Critical speed, Stability, Mode shapes

Ø Gyroscopic effect

Ø Prestress effect

Capabilities

Rotordynamics forRotordynamics for®

Ø Harmonic analysis

Ø Lateral – Torsional steady state forced vibration

Ø Damped – Undamped analysis

Ø Harmonic analysis

Ø the excitation frequency is “k” multiple of the rotor speed

Ø constant rotor speed – variable excitation frequency

Ø constant excitation frequency – variable rotor speed

Ø Gyroscopic effect

Ø Prestress effect

Capabilities

Rotordynamics forRotordynamics for®

Capabilities

Ø Transient analysis

Ø Lateral – Torsional forced vibration

Ø Damped – Undamped analysis

Ø Transient analysis

Ø Numerical simulation for constant rotor speed

Ø Numerical simulatin of transition through the resonance

Ø Gyroscopic effect

Rotordynamics forRotordynamics for®

By using the UPF create new elements for nonlinear rotor dynamics.

Non-linear coupling elements between rotating and non-rotating parts

Ø slide bearings

Ø roller bearings

Ø squeeze film dampers

Ø seals

Ø contact model between rotating and non-rotating parts

Ø coupling by magnetic field

Ø self-lubricating bearing

Future

Rotordynamics forRotordynamics for®

∅ d1

L1

DISC1DISC21∅ d2 ∅ d3 ∅ d4

L2 L1L1

DISC1

DISC2

KZ,BZ

KY,BY

KY,BY

KZ,BZ

A rotor with two disks

Rotordynamics forRotordynamics for®

∅ d1

L1

DISC1DISC21∅ d2 ∅ d3 ∅ d4

L2 L1L1

8 .00 E+0 5

1 .20 E+0 6

1 .60 E+0 6

2 .00 E+0 6

0 2 000 4 000 6 00 0 8 00 0 1 00 00

N = RPM [min-1]

Ky [N/m]

Damping By = 1000 Ns/m

Stiffnes Ky = 106 - 100⋅n + 0,02⋅n2

9 .00E+08

9 .50E+08

1 .00E+09

1 .05E+09

1 .10E+09

0 2000 4000 6000 8000 10000

N = RPM [min-1]

Kz [N/m]

Damping Bz = 2000 Ns/m

Stiffnes Kz = 109 – 25 000⋅n + 3⋅n2

A rotor with two disks

Rotordynamics forRotordynamics for®

A rotor with two disksModal analysis for variable rotor speed (0-10000 RPM)

Rotordynamics forRotordynamics for®

Mode 1 – f1 = 10 Hz ( n = 3000 rpm )

f1

Mode 2 – f2 = 23 Hz ( n = 3000 rpm )

f2

Mode 3 – f3 = 33 Hz ( n = 3000 rpm ) Mode 4 – f4 = 75 Hz ( n = 3000 rpm )

f3 f4

A rotor with two disksModal analysis for variable rotor speed

Rotordynamics forRotordynamics for®

Z_3

Y_3

DISC1

A rotor with two disksHarmonic analysis

Rotordynamics forRotordynamics for®

A rotor with two disksHarmonic analysis

f1 = 10,9 Hz ( n1 = 654 rpm )

f1 f2

f2 = 32,8 Hz ( n2 = 1968 rpm )

f3

f3 = 72,1 Hz ( n3 = 4326 rpm )

f4

f4 = 102,9 Hz ( n4 = 6174 rpm )

Rotordynamics forRotordynamics for®

A rotor with two disksTransient analysis - Numerical simulation for constant rotor speed

DISC1

DISC2

Impact force

Unbalance

Rotor speed = 1200 RPMUnbalance = 0.0001 kg.mImpact force = 10 N

Rotordynamics forRotordynamics for®

A rotor with two disksTransient analysis - Numerical simulation for constant rotor speed

Rotordynamics forRotordynamics for®

A rotor with two disksTransient analysis - Numerical simulatin of transition through the resonance

Rotordynamics forRotordynamics for®

A rotor with two disksTransient analysis - Numerical simulatin of transition through the resonance

Rotordynamics forRotordynamics for®

Rotordynamics Rotordynamics forfor ®

www.www.svsfemsvsfem..czczrotor@rotor@svsfemsvsfem..czcz

Ø Users’ manual + tutorials.

Ø Demo version.

Ø Technical support.

For more informations please contact: