ansys, inc. proprietary © 2004 ansys, inc. chapter 3 ansys v9.0 multiphysics & electromagnetics

ANSYS, Inc. Proprietary© 2004 ANSYS, Inc.

Chapter 3

ANSYS v9.0Multiphysics & Electromagnetics

Chapter 3

ANSYS v9.0Multiphysics & Electromagnetics


ANSYS Workbench Electromagnetics

ANSYS Workbench Electromagnetics

ANSYS, Inc. Proprietary

© 2004 ANSYS, Inc.

October 1, 2004Inventory #002156

3-39.0 New Features

Contents

Workbench Electromagnetics– Workbench Emag Roadmap

– Design Modeler• Enclosure Symmetry• Winding Bodies• Winding Tool

– Simulation


© 2004 ANSYS, Inc.


3-49.0 New Features

Workbench Emag Roadmap

• LF Emag capability will be exposed over several release cycles:– 3D Magnetostatics (9.0)– 3D Electrostatics (10.0)– 3D Current conduction– Circuit elements– Time transient & 2D

• Workbench v9.0 is the first release with electromagnetic analysis capability. – Support solid and stranded (wound) conductors– Automated computations of force, torque, inductance, and coil

flux linkage.– Easily set up simulations to compute results as a function of

current, stroke, or rotor angle.

• Workbench Emag capability is mapped to & accessed via:– ANSYS Emag (stand alone or enabled task) – ANSYS Multiphysics license keys.


© 2004 ANSYS, Inc.


3-59.0 New Features

Workbench Emag Markets

Target markets: • Solenoid actuators• Permanent magnet devices• Sensors• Rotating Electric machines

– Synchronous machines– DC machines– Permanent magnet machines


© 2004 ANSYS, Inc.


3-69.0 New Features

Contents


– Design Modeler• Enclosure Symmetry• Winding bodies• Winding Tool

– Simulation


© 2004 ANSYS, Inc.


3-79.0 New Features

Enclosure Symmetry

• Feature: The Enclosure feature now supports symmetry models when the enclosure shape is a box or a cylinder:

– Up to 3 three symmetry planes can be specified. – Full or partial models can be included in the Enclosure. – During the model transfer from DesignModeler to Simulation, the enclosure feature with symmetry planes forms two kinds of named selections:

– Open Domain– Symmetry Plane


© 2004 ANSYS, Inc.


3-89.0 New Features

Contents


– Design Modeler• Enclosure Symmetry• Winding bodies• Winding Tool

– Simulation


© 2004 ANSYS, Inc.


3-99.0 New Features

Winding Bodies & Tool

• Feature: Design Modeler (DM) includes two new tools to allow a user to easily create current carrying coils:

– Winding Bodies: Used to represent wound coils for source excitation. The advantage of these bodies is that they are not 3D CAD objects, and hence simplify modeling/meshing of winding structures.

– Upon “attach to Simulation”, Winding Bodies are assigned as Conductor bodies.

– Winding Tool: Used to create more complex coils for motor windings. The Winding Tool uses a Worksheet table format to drive the creation of multiply connected Winding Bodies. Or a user can read in a text file created by MSExcel.

• Benefits: Very easy to use, rapid creation of coil windings.


© 2004 ANSYS, Inc.


3-109.0 New Features

Winding Bodies

A line body can be promoted to a winding body. Turns and cross-section (CS) dimensions are entered

Winding cross-section displayed

Tangent orientation vector (blue arrow) defines direction of current.


© 2004 ANSYS, Inc.



Winding Tool

Complex coil windings may be created using the Winding Tool:• The Winding Tool inserts a “Winding#” into the model tree. • A “Details” view is used for geometric placement.


© 2004 ANSYS, Inc.



Winding Tool

Each Winding consists a number of related Winding Bodies.The related Winding Bodies are shown in the Parts/Bodies branch:

Winding Bodies


© 2004 ANSYS, Inc.



Winding Table File

• Each Winding has a Winding Table File associated with it. • The Winding Table File can be created directly in DM• The Winding Table File can be exported to or imported from a text file.• Each row corresponds to a created Winding Body


© 2004 ANSYS, Inc.



Winding Table File

• The Winding Table File can be exported to or imported from a text file.


© 2004 ANSYS, Inc.



Winding Tool Example

Winding 1 highlighted with rotor

Complete DC Motor model


© 2004 ANSYS, Inc.



Winding Options

• Coils may have different radii between IN & OUT slots• Multiple coils may be stacked in the same slot


© 2004 ANSYS, Inc.



Winding Options - Skew

• A skew angle may be identified for the coil winding slots• Many motor designs employ a skewed coil form.


© 2004 ANSYS, Inc.



Winding Slot Clash Detection

Winding Tool automatically detects if the coil clashed with another part and warns the user


© 2004 ANSYS, Inc.



Contents

Workbench Electromagnetics– Workbench Emag Roadmap– Design Modeler

• Enclosure Symmetry• Winding bodies• Winding Tool

– Simulation• Tools Layout• Winding bodies• Material Properties• Air Gap Mesh Sizing• Conductors• Solution


© 2004 ANSYS, Inc.



Simulation Tools Layout

Electromagnetic Toolbar

Simulation Environment:•Emag boundary conditions•Conductor source excitation

Solution Results•Field•Force•Torque•Inductance •Flux linkage


© 2004 ANSYS, Inc.



Winding Body Transfer in Simulation

Winding bodies are automatically assigned to conductor bodies. From the Winding Tool, each Phase Winding is assigned as a unique conductor.In this example, Conductor A consists of 2 winding bodies.


© 2004 ANSYS, Inc.



Material Property Support

Both linear & nonlinear Emag materials are supported by Engineering Data:

• Soft materials (Steel, iron, etc.)– Constant (isotropic)– Laminated (orthotropic)– Linear/nonlinear (single B-H curve)

• Hard materials (NdFeB, SmCo, Alnico)– Linear– Nonlinear


© 2004 ANSYS, Inc.



Materials – BH Curves

BH curves with up to 500 data points are supported


© 2004 ANSYS, Inc.



Materials - Permanent Magnets

Coordinate systems are used to align the polarization axis of a magnet. Cartesian and Radial Magnetization are supported.


© 2004 ANSYS, Inc.



Air Gap Mesh Sizing

• Requirement: . In an electromagnetics analysis models typically include narrow gaps between parts such as rotors and stators. It is important to have a refined mesh in these gaps.

• Feature: Air Gap Mesh sizing. As for other mesh controls, air gaps are assigned under Advanced Controls in the Mesh Detail.

• Benefits: Easy to use mesh refinement, resulting in more accurate analysis results.


© 2004 ANSYS, Inc.



Air Gap Mesh Sizing


© 2004 ANSYS, Inc.



Conductor Objects identify conductors for excitation, inductance, and Post processing. Can be scoped to solid bodies (solid conductors), or Winding Bodies (wound coils)

Excitation: Supports voltage and current loading for solid conductors. Current and phase angle are supported for Winding Bodies.

Conductor Objects


© 2004 ANSYS, Inc.



Solution Results


© 2004 ANSYS, Inc.



Vector & Contour Plots

Vector / Contour is selected in the Solution objects “Definition”


© 2004 ANSYS, Inc.



Inductance & Flux Linkage

Solution branch can insert Inductance & Flux linkage post processing calculations. Self and mutual inductance is computed.


© 2004 ANSYS, Inc.



Parameter Sweeps

The Emag analysis can be fully parameterized so that a user can easily extract force or torque versus rotor position etc.

An example will be available to demonstrate this shortly!


ANSYS Multiphysicsv9.0

ANSYS Multiphysicsv9.0


© 2004 ANSYS, Inc.



Contents

• ANSYS Multiphysics – Thermoelectric Direct Coupled Field

– LF Electromagnetics

– HF Electromagnetics


© 2004 ANSYS, Inc.



• Feature: New thermoelectric analysis option on the series 22X direct coupled-field elements includes: – Seebeck, Peltier, Thomson effects

– Transient electrical effects (capacitive “damping”)

• Benefit: Addresses new thermoelectric applications where temperature stabilization, temperature cycling, compact or pinpoint cooling are required.

• Applicable to: PLANE223, SOLID226, SOLID227. Steady-state & transient analysis.

Thermoelectric Analysis


© 2004 ANSYS, Inc.



Thermoelectric Elements

Name

PLANE223 SOLID226 SOLID227

2-D 8-node 3-D 20-node 3-D 10-node

Coupled-field solid

Geometry

Product MP,PP,ED

KEYOPT(1) 110 (thermoelectric analysis)

DOFs-ReactionsTemperature (TEMP) – Heat flow (HEAT)

Electric scalar potential (VOLT) - Electric current (AMPS)

Material Properties

KXX, KYY, RSVX, RSVY, SBKX, SBKY, DENS, C, ENTH, PERX, PERY

KZZ, RSVZ, SBKZ, PERZ

LoadsSF: CONV, HFLUX, RDSF

BF: HGEN

KEYOPT(3)0 - Plane

1-Axisymmetric


© 2004 ANSYS, Inc.



Thermocouple example

Voltage distributionTR= 25 ºC

TC= 0 ºC

TH= 100 ºC

Material AMaterial B

Material B

VS= 0.0425 V

Differential junction temperature results in a 42 mV potential difference


© 2004 ANSYS, Inc.



Peltier Cooler Example

p-type material(=230Volt/ oC)

n-type material(= -195Volt/ oC)

Iout

Iin= 10 A

conductor

Cold side T= -3 oC

Hot side T= 54 oC

Temperature distribution:

10A current flow results in a 57oC temperature differential.


© 2004 ANSYS, Inc.



Example markets and applications for the thermoelectric analysis capability:

• Electronic and optical component cooling– CPU, photo-detectors, low noise amplifiers, laser diodes, fiber optics

• Consumer products– Portable food/beverage coolers, automotive seat cooling/heating

• Medical, laboratory and scientific equipment– Blood analyzers, thermal cycling devices (blood, lymph, DNA), portable

insulin coolers, heart and eye surgery, hypothermia blankets

• Military & Space– Night vision equipment, guidance systems, pilot suit temperature regulation

• Indoor environmental devices– Conditioners, fans, humidifiers

Markets and Applications


© 2004 ANSYS, Inc.



Contents

• ANSYS Multiphysics – Direct Coupled Field

– LF Electromagnetics• Electromagnetic forces & torque• Conductance Matrix

– HF Electromagnetics


© 2004 ANSYS, Inc.



Electromagnetic Force & Torque

• Feature: New command and underlying numerical (Virtual Work force) calculation to summarize electromagnetic force and torque.

• Command: EMFT• Benefit: Easier to use, faster, & more

accurate.Electric and magnetic methodology are now the same – consistency.

• Applicable to: SOLID117, PLANE121, SOLID122, SOLID123.


© 2004 ANSYS, Inc.



Electromagnetic Forces – 2D

Potential distribution

Electrostatic forces

Electrostatic Forces, 2D MEMS comb drive example


© 2004 ANSYS, Inc.



Electromagnetic Forces – 2D

g

VN

x

WF rt

20

arg

Electrostatic Force (N)

Driving (x) Transverse (y)

Simplified analytical [1,2](Ignores fringing effects)

5.3110-9 0.0

ANSYS (Maxwell Stress Tensor)

3.5510-9 0.00610-9

ANSYS (New Virtual Work)

5.6510-9 0.00510-9

REFERENCES

1. T.-C. H. Nguyen W.C. Tang and R.T. Howe. Laterally driven polysilicon resonant microstructures. Sensors and Actuators A, 20:25–32, 1989.

2. M.W. Judy W.C. Tang, T.-C.H. Nguyen and R.T. Howe. Electrostatic-comb drive of lateral polysilicon resonators. Sensors and Actuators A, 21-23:328–331, 1990.

MEMS comb drive example results:


© 2004 ANSYS, Inc.



Electromagnetic Forces- 3D

1/8th symmetry Potential distribution

Electrostatic forces

Half symmetry problem description

Concentric sphere verification benchmark:


© 2004 ANSYS, Inc.



Electromagnetic Forces- 3D

Concentric sphere results:

REFERENCES

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capsph.html#c1

Radial Electrostatic Force (N)

Fa (inner) Fb (outer)

Analytical model

2.2310-6 -0.5610-6

ANSYS (Maxwell Stress Tensor)

1.5910-6 -0.7910-6

ANSYS (New Virtual Work)

2.2110-6 -0.5510-6

22

20

11

2

baa

V

a

WF ra

22

20

11

2

bab

V

b

WF rb


© 2004 ANSYS, Inc.



Electromagnetic forces – 3D

TEAM20 Solenoid Benchmark Results:

Vertical (z-direction) force (N)

1000 A-turns 3000 A-turns 5000 A-turns

Experimental (target) 8.10 54.4 80.1

ANSYS (Old Virtual Work) 7.24 51.3 76.7

ANSYS (New Virtual Work) 7.25 51.4 76.8

REFERENCES

1. M. Gyimesi, D. F. Ostergaard, “Analysis of Benchmark Problem TEAM20 with Various Formulations”, Proceedings of TEAM Workshop, COMPUMAG, Rio, 1997.

2. M. Gyimesi, D. F. Ostergaard, “Mixed Shape Non-Conforming Edge Elements”, IEEE Transactions on Magnetics, Vol. 35 No. 3, 1999, pp. 1407-1409.

3. M. Gyimesi, D. F. Ostergaard, “Non-Conforming Hexahedral Edge Elements for Magnetic Analysis”, IEEE Transactions on Magnetics, Vol 34 No. 5, 1998, pp. 2481-2484.

See also new Verification Example: VM241.


© 2004 ANSYS, Inc.



Conductance Matrix

• Feature: A new macro is now available to extract conductance from multi-conductor systems. This macro, which is used much like the CMATRIX macro for capacitance, allows you to extract self and mutual conductance terms so that equivalent circuit lumped conductors can be defined for use in circuit simulators.

• Command: GMATRIX• Benefit: Provides improved lumped parameter connectivity with

circuit simulators. Combined with CMATRIX, and LMATRIX, a user can now extract L, C & G matrices for subsequent use circuit simulators.

• Applicable to: –SOLID5,PLANE67,LINK68,SOLID69,SOLID98–PLANE230,SOLID231,SOLID232–Not available with Trefftz method.


© 2004 ANSYS, Inc.



Contents

• ANSYS Multiphysics – Direct Coupled Field– LF Electromagnetics– HF Electromagnetics

Frequency Selective SurfacesLumped CircuitsFast Frequency Sweep VTSPICE sub-circuit extraction (Beta)Smith ChartsSpecific Absorption Rate (SAR)Multi-port Power Calculation


© 2004 ANSYS, Inc.



Frequency Selective Surfaces

• Features: –To compliment the Floquet periodic boundary condition (released at 8.1), a plane wave source port (via HFPORT) is now available to launch a plane wave for a scattering analysis of a periodic structure. Such a structure is commonly referred to as a Frequency Selective Surface (FSS).–Radar Cross Section (RCS) results can be displayed and listed for 2D TE and TM incident plane waves (via PLHFFAR and PRHFFAR). –FSS Reflection and transmission properties are calculated using the new FSSPARM macro.

• Benefit: A new capability introduced to address a growing market need to analyze FSS.

• Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid) & PML.

Incident Plane WaveIncident Plane Wave

Periodic StructurePeriodic Structure


© 2004 ANSYS, Inc.



Frequency Selective Surfaces

FSS example: Plane wave incident at 45o

90

45

x

y

z

E-Field (x) ContoursE-Field (x) Contours

Far field patternFar field pattern


© 2004 ANSYS, Inc.



Lumped HF Circuit Elements

• Feature: HF Lumped “RLC” circuit elements. They are applied to the mid-nodes of element edges using the BF command.

• Benefit: A new capability that can be used to greatly simplify a HF analysis in a similar manner to our LF Emag circuit elements. The lumped circuit greatly reduces the number of DOF’s.

• Application: Use to simulate passive devices like resistors, or to simplify a structure when fringe effects at discontinuities can be ignored.

• Applicable to: HF119, HF120 (Hex, Tet, Wedge and Pyramid).

Microstrip lineMicrostrip line

FEA Domain (Mesh)FEA Domain (Mesh)

Lumped RLC circuit modelLumped RLC circuit model


© 2004 ANSYS, Inc.



Lumped HF Circuit Elements

• Command: BF, <Node>, Lump, <value1>

• Six types of lumped circuits are available, value1 of the BF command is used to specify which :

– Complex impedance – Shunt RCL circuit – Series RL with shunt C – Series RCL – Series RC with shunt L – Series LC with shunt R


© 2004 ANSYS, Inc.



SPICE Sub-circuit Extraction

• Feature: SPICE Compatible Sub-circuit Extraction. Feature synthesizes an RLCG equivalent circuit for passive multi-port electromagnetic structure.

• Commands: SPICE

• Benefit: Ability to easily connect ANSYS to system level EDA circuit simulation tools for signal integrity applications. Allows ANSYS to start to address high frequency time domain analysis. Extracted circuit is SPICE compatible.

• Usage: SPICE sub circuit is extracted from S-parameter frequency sweep.

• Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid). S parameter extraction only.

9.0 BETA


© 2004 ANSYS, Inc.



3rd Party EDA Signal Integrity

tool suite

ANSYS Multiphysics

SPICE Sub-circuit Extraction

Integrating ANSYS HF Emag into Signal Integrity Process Flow:

Parametric GeometryCreation

Parametric GeometryCreation

HF Emag solver

HF Emag solver

S-parameter sweep

S-parameter sweep

SPICE circuit extraction

SPICE circuit extraction

SPICE simulation

SPICE simulation

Time Transient Waveforms

Time Transient Waveforms

Design RulesDesign Rules

9.0 BETA


© 2004 ANSYS, Inc.



Fast Frequency Sweep VT

• Feature: The fast Frequency Sweep VT module has been enhanced using a perfect absorber. This provides a 20% faster solution than the original VT method.

• Commands: SPSWP, HROPT

• Benefit: Fast S-parameter calculations over a wide frequency range.

• Usage: Frequency Sweep VT is an additional charge module that can be added to ANSYS Multiphysics.

• Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid). S parameter extraction only.


© 2004 ANSYS, Inc.



Smith Chart & Network Parameters

• Features: – Conversion of scattering (S), admittance (Y) or impedance (Z)

parameters for display on a Smith Chart. – Display the required network parameters and generate a new

Touchstone file for the required parameter. – Plot the required network parameters as the response of the

frequency on an x-y graph. • Commands: PLSCH, PLSYZ, PRSYZ • Benefit: Ability to display results in formats that are widely accepted in

the industry. Easier for RF engineers to understand ANSYS results! • Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid).


© 2004 ANSYS, Inc.



Specific Absorption Rate (SAR)

Features: Specific Absorption Rate (SAR) Calculation for lossy materials. Can plot or list SAR distribution using ETABLE of ANSYS postprocessor.

Commands: SAR is calculated when a mass density of the material is defined by the MP command. Results are stored in the HF119 and HF120 Item and Sequence Numbers Table.

Benefit: Ability to compute SAR is an important capability required for primarily biomedical studies of effects of HF energy on living tissue.

Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid).


© 2004 ANSYS, Inc.



Multi-Port Power Calculation

Feature: Power Calculation for Multi-port High-Frequency networks. Feature provides:

• Input/Output power at ports• Dissipated power in multi-port system• Power reflection/transmission coefficient• Return loss and insertion loss at ports

Command: HFPOWER

Benefit: Ability to compute SAR is an important capability required for primarily biomedical studies of effects of HF energy on living tissue.

Applicable to: HF119, HF120.(Hex, Tet, Wedge and Pyramid).

ansys, inc. proprietary © 2004 ansys, inc. chapter 3 ansys v9.0 multiphysics & electromagnetics

Documents

ansys emag

ansys v9

winding tool

connected winding bodies

workbench emag capability

tool simulation slide

d workbench v9

enclosure feature