ANSYS CFXRelease 17.0

Areas of DevelopmentTurbomachinery Blade RowWorkflowGeneral Physics ModelingUser Environment

TURBOMACHINERY BLADE ROW

3

Blade Row: Mixing Plane ImprovementsChanged default downstream velocity constraint to ‘Total Pressure’

Permits downstream velocity profile to naturally adjust to downstream influences

Improved energy closureHigher solution accuracyReduce reflections at interface

R16

R17

Transient Blade Row Methods With Pitch-ChangeANSYS CFX transient pitch-change models

Profile Transformation

(PT)

Time Transformation

(TT)

Fourier Transformation

(FT)Small/Moderate Pitch

• Single Stage • Multistage

• Frozen gust • Single Stage • Multistage

• Frozen gust • Single Stage • Multistage • Blade Flutter

Small/Moderate Pitch Large Pitch

PT TT FT

Transient interaction +

Correct blade passing frequencies

Transient interaction

Full-wheel Model

Reduced Model

Solve on Reduced Geometry

Transient Blade Row MethodsExtended models and improved usability

Time Transformation and Fourier TransformationMulti-stage, Asymmetric flow, Multi-disturbance

Transient Blade Row with CHTMixing plane improvementsConvergence monitoring for cyclically periodic flow ( )Harmonic Analysis: frequency-domain method ( )

Transient Blade Row: TT for MultistageModeling multistage with combination of TT and Single-Sided Time Transformation (STT) interfaces

Flexibility in modeling multi-stage with combination of TT, STT and PT interfaces for wide range of machinesFurther improvement to aerodynamic performance prediction

Transient Blade Row: FT-TRS with AsymmetryCoupling single rotor passage to 360 domain with Fourier Transformation (FT)Handle single and multi-frequential disturbances

Examples of large single disturbance

Example of large multi-frequential disturbances

Compressor operating off-design - Fan in crosswind- Boundary layer ingestion- Ground vortex ingestion

Impeller in a vaneless volute

Impeller in a vaned volute, with two disturbances seen by rotor1) diffuser blade passing2) one-per-rev variation due to volute

Transient Blade Row: FT Multi-disturbanceFourier Transformation (FT) with multiple disturbances

Frozen gust analysis with inlet and outlet disturbances

Transient Blade Row: FT for MultistageFourier Transformation (FT) with

multiple pitch ratiosmultiple frequencies

All the benefits of FT method – now also for multi-stage analysis

Incompressible fluidsLarge pitch ratioetc.

Transient Blade Row: with CHTAltered solid thermal response to combine CHT with TBR

Transient Blade Row: UsabilityCyclic and polar plots in solver monitors ( )

Overlay multiple common blade passing periods Clear visualization of convergence to quasi-steady solutionVisible beta feature

TBR restart with time-step size changeStop FT or TT and then resume with larger time stepReduce the overall simulation time required to reach convergence

Transient Blade Row: Harmonic Analysis ( )Introduction of frequency-domain method

A priori specification of resolved frequencies highest solution efficiencyAdvanced implementation with numerous advantages

Truly non-linear, no shock smearing, …

Can be used with all existing pitch-change methods

Full wheel, PT, TT, and FT

Rotor 67 fan test case: equivalent results to full wheel, but ~10X faster than with FT

and ~50X faster than full wheel

WORKFLOW

14

User Location (Surface) OutputResults output to arbitrary surface locations

Generate significantly less dataLeaner simulation and analysis

Significant impact for large transient cases

Data (disk space) may be reduced by orders of magnitudeLess data sent between CFD-Post engine and GUI during post-processing

Analogous capability for Fluent and CFX

Arbitrary surface output location (independent of solver mesh)

Live CFX Solution Monitoring in CFD-Post ( )Building on “User Surface” output

FSI with CFX and Systems Coupling 2-Way FSI between CFX and Mechanical

Supersede MFX with workflow and technology consistent with Fluent-Mechanical couplingInitial support for steady and transient exchange of forces and resultant displacements

GENERAL PHYSICS MODELING

18

Intermittency Transition ModelOne-Equation Intermittency-based Transition Modelling

Significant advancement of the -Remodel

Reduce number of equationsGalilean invariantSimplified correlationsCrossflow instability

Advances in Scale-Resolving Turbulence ModellingNew Shielded Detached Eddy Simulation (SDES)

Stronger shielding than Delayed DESClear separation of RANS and LES modeNew option for existing DES SST

New Stress-Blended Eddy Simulation (SBES)

Incorporates and builds on SDESFaster switch to LES modesCombine RANS and LES, with blending (f)

Currently using SST and WALE LES Blended eddy viscosity

SBESLEStSBES

RANSt

SBESt ff 1

USER ENVIRONMENT

23

CFD-Post Charts of CFX Monitor DataAccess to CFX monitor data for use in charts in CFD-PostInclude convergence plots in reports generated with CFD-Post

Time AnimationEase-of-use for transient post-processing

‘Music player’-like controlPlay/stopNext/previous time stepFirst/last time step

Options toSpecify desired transient range by time step, time, or crank angleControl which frame to use when between available framesSave time animation to movie file

GUI-Engine Communication EfficiencyAvoid compression/decompression during data transferImprove interactive efficiency/performance

More data transferredBut: no compression/decompression cost

R16 R17

Support for STL SurfacesAbility to import/export *.stlformat geometry definition

Define post-processing locations Import as contextual geometryExport any surface locator for other uses

e.g. surfaces in Fluent

Original CAD geometry surfaces around flow domain brought in as STL to give improved context to simulation results