ansys rotordynamics beac… · 1 © 2011 ansys, inc. 8/29/11 ansys rotordynamics. 2 © 2011 ansys,...

© 2011 ANSYS, Inc. 8/29/111

ANSYS Rotordynamics

© 2011 ANSYS, Inc. 8/29/112

Introduction

Benefits of Using ANSYS

Continual Enhancements

Analysis Types

Rotordynamics in ANSYS WorkbenchRotordynamics Documentation

Summary and Questions

Outline

© 2011 ANSYS, Inc. 8/29/113

Many industries use machines with rotating components

• Power generation, transportation, electronics, chemical processing

Comprehensive design of rotating components, using high-fidelity tools, is essential to achieve machine reliability, stable range of operation, low noise at desired speeds and loads etc.

• Turbomachinery, mixers, disk drives, generators etc.

ANSYS has expanded its rotordynamics capability to offer integrated solutions to all such industries and machine types

Introduction

© 2011 ANSYS, Inc. 8/29/114

Complete rotordynamics analysis with ANSYS, enabled by….

• CAD import and automatic meshing

• Library of elements• All analysis types (including

pre-stress)• Dedicated post-processing• Multi-spool dynamics

simulation• Direct connection to bearing

codes• Account for the flexibility of

the supporting structure and/or the disks

• Connect directly to other ANSYS tools via Workbench (DesignXplorer)

Benefits of Using ANSYS

© 2011 ANSYS, Inc. 8/29/115

Continual Enhancements

© 2011 ANSYS, Inc. 8/29/116

Release 10.0 Enhancements

New Features Commands

Activate gyroscopic effect at solver level CORIOLIS

Specify rotational velocity for full model and components

OMEGA CMOMEGA

Develop Campbell diagram PRCAMPPLCAMP

Include gyroscopic effect with LINE and MASS elements

MASS21BEAM188 BEAM189

© 2011 ANSYS, Inc. 8/29/117


Include gyroscopic effect with SOLID elements

SOLID185SOLID186SOLID187

Perform a harmonic response to synchronous and asynchronous excitations

SYNCHRO

Perform Campbell analysis of a pre-stressed structure CAMPBELL

Visualize and printout the orbits characteristics

PLORB PRORB

New variable bearing element COMBI214


© 2011 ANSYS, Inc. 8/29/118



Include gyroscopic effect with SHELL elements

SHELL181SHELL281

Replace damped eigensolver with faster and more accurate solver

MODOPT, DAMP

Improve performance for large models (1 Mdof) in reduced damped eigensolver

MODOPT, QRDAMP

Include gyroscopic effect with new generation axi-harmonic elements

SOLID272SOLID273

Add dedicated Rotordynamics Guide

Documentation

© 2011 ANSYS, Inc. 8/29/119



New APDL Math extends APDL scripting capabilities *EIGEN

Damped (MODOPT,DAMP) extraction method supported in Distributed ANSYS

MODOPT, DAMP

QR damped (MODOPT,QRDAMP) eigensolver now reuses existing undamped modes

MODOPT, QRDAMP

Linear Perturbation enables a modal analysis to use the tangent stiffness matrix at any point in a previous analysis

PERTURB

*SMAT, K, D, IMPORT, FULL, file.full, STIFF*SMAT, M, D, IMPORT, FULL, file.full, MASS*SMAT, G0, D, IMPORT, FULL, file.full, DAMP

*SMAT, zMG0, Z, COPY, M*AXPY,, alpha, G0, 1,, zMG0*SMAT, zK, Z, COPY, K

/SOLUANTYPE, MODALMODOPT, UNSYM, 6*EIGEN, zK, zMG0,, EiV, EiMFINIreduced processor time for large

models

better performance for Campbell Diagram generation

more general method for rotordynamics pre-stress modal analysis

© 2011 ANSYS, Inc. 8/29/1110

Support in Workbench Mechanical for:

• Campbell Diagrams• Full Damped, Reduced Damped solvers• Animation with Decay• Rotational Velocity with Coriolis Effect• Post-process Multi-step modal analysis


© 2011 ANSYS, Inc. 8/29/1111

Analysis Types

© 2011 ANSYS, Inc. 8/29/1112

Modal Analysis

Orbit Plot

Complex Frequency Printout

Specify the rotational velocity and activate

the Coriolis effect

Deformed ShapeAnimation

© 2011 ANSYS, Inc. 8/29/1113

Modal Analysis – Campbell Diagram

Set up a Multiple Load Step Modal

Analysis

Frequencies - Whirls - Stability

Critical Speeds

Logarithmic Decrement

© 2011 ANSYS, Inc. 8/29/1114

Harmonic Analysis – Unbalance Response

Specify the Unbalance Force on Inner Spool

Orbit PlotUnbalance Response

© 2011 ANSYS, Inc. 8/29/1115

0 0.5 1 1.5 2 2.5 3 3.5 40

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

Time (s)

Rot

atio

nal v

eloc

ity (

rpm

)

Transient Analysis 1

Start-up and Stop Simulation

Transient Response

Specify the Rotational Velocity

vs. Time

© 2011 ANSYS, Inc. 8/29/1116

Transient Analysis 2

Stability Verification

Transient Orbits

Specify a Short Duration Force

© 2011 ANSYS, Inc. 8/29/1117

Rotordynamics in ANSYS Workbench

© 2011 ANSYS, Inc. 8/29/1118

Rotordynamics in ANSYS Workbench

Bearings

Initial 3D geometry

Final axisymmetric model

Model consists of• Shaft• Disk• Bearings

Disk added

© 2011 ANSYS, Inc. 8/29/1119

Rotordynamics in ANSYS WorkbenchProject view in ANSYS

WorkbenchSimulation process

GeometryMesh

Simulation

Design Exploration

Tools

Parameters: geometry &

bearing stiffness

© 2011 ANSYS, Inc. 8/29/1121

Simulation & Results

Campbell Diagram

Critical speeds

Mode visualization(animation with

decay)

© 2011 ANSYS, Inc. 8/29/1122

Design Exploration

• Input parameters– Disk radius– Shaft radius– Bearing stiffness

• Output parameters– Critical speeds

Automated parametric investigation

Sensitivity plots

© 2011 ANSYS, Inc. 8/29/1127

SummaryThe previous slides have described the elements

of complete rotordynamics analysis, with ANSYSØ Key enabling features:

– CAD import and automatic meshing– Library of elements– All analysis types (including pre-stress)– Dedicated post-processing– Multi-spool dynamics simulation– Direct connection to bearing codes– Account for the flexibility of the

supporting structure and/or the disks– Connect directly to other ANSYS tools

via Workbench (DesignXplorer)Ø The result: Faster, more complete and accurate machine analysis… with ANSYS

ansys rotordynamics beac… · 1 © 2011 ansys, inc. 8/29/11 ansys rotordynamics. 2 © 2011 ansys,...

Documents