BLADE3DR - turboaerodesign.comBlade three-dimensional profile design and aero/hydrodynamic analysis in turbomachinery ... (by Ansys) Over 12 year-use in personal aero-design tasks

BLADE3DRVersion 3.3

2018

Dr. Justin (Jongsik) Oh

www.TurboAeroDesign.com

2018www.TurboAeroDesign.com

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INTRODUCTIONBLADE3DR ver. 3.3

Blade three-dimensional profile design and aero/hydrodynamic analysis in turbomachinery

A single row blade

Design parameters

Hub and shroud contours

Blade camberline metal angle

Blade normal thickness

Aerodynamic analysis options

Blade loading analysis• SCM (Streamline Curvature Method, or Velocity Gradient Method)

• FEM (Finite Element Method)

Blade 3D simplified CFD• Explicit time-marching method using body forces for turbulent viscous terms

• No rotor tip clearance

• Real gas option included


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Development was motivated by personal needs for Better Performance and Reliability at aero design tasks since 2002 while using some commercial software, including

CCAD (by Concepts ETI, but now Concepts NREC)

COMIG (by NREC, but now gone)

BladeGen and BladeGenPlus (by AEA Technology)

AxCENT (by Concepts NREC)

BladeModeller (by Ansys)

Over 12 year-use in personal aero-design tasks at various applications, still evolving.


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Program Strucuture Windows-based ( FORTRAN + Visual Basic ) Aiming for use of PC or laptops Programs are installed in “C:\OJS\TurboSW\Blade3DR\Ver3_3\”. All input/output files are located in “C:\OJS\TurboSW\Blade3DR\Ver3_3\Work\”. All input/output file names are pre-determined and fixed. When tasks are done, all necessary files should be copied to the local folder using the data management menu.

Program Limits A single row of blades Max. two-row tangential splitter blades No fillets Currently limited CAD export options (DXF and STL) *

Program Plus Capabilities Two different methods for blade loading analysis (SCM + FEM) 3D compressible or incompressible turbulent CFD Blade rotation by specified angle (useful for IGV model) Large single screen for better work performance (that I love) Supplementary viewer + Text viewer Total 21 spanwise uniformly-spaced layers (fixed) Two curve options

• Spline **

• Bezier polynomial


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(*) When professional s/w expertise is added,it will be extended to IGES and STEP, etc.However, a solid can be easily created fromSTL with any CAD programs.

(**) In some situation, using Spline providesbetter work performance than Bezier. You willneed both.


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• Large single screen for edit

• Supplementary viewer

• Text viewer

• Easy-access buttons

• File inputs

.rtzt

.ojs

.curve

Meanline output from

all my design programs

The .rtzt file is of a blade meanline format,

shared with all my programs and also with Ansys

BladeModeller (See Appendix).

The .ojs file is of directly-saved data of Blade3D.

The .curve files are Ansys Turbogrid inputs.

Just for illustration (of arbitrary design) to show capabilities of two-row splitters with real gas

Centrifugal compressor impeller using HFC-134a refrigerant


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• 2D DXF

• 3D DXF wireframe

• 3D STL

• Direct inputs for

Ansys Turbogrid (.curve)

Numeca FineTurbo (.geomturbo)


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Dynamic View

Spanwise Distributions


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• Various setting options for

better design performance


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• Various edit options for

better design performance

Spline

Bezier Polynomial

• BETA or THETA edit


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• Various edit options for better design performance

• Edit while looking at hub and shroud curves together

• By default, all tangential splitter-blades follow full-blade

angles. However, they can be changed via Option menu.


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• Edit while looking at hub and shroud curves together

• All tangential splitter-blade thicknesses are independently

changeable.

• Sometimes “spline” curve is better than “Bezier polynomial” at

heavy rate of changes in the distribution. You will need both.


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• Total 5 Options

Circle

Ellipse

Bezier *

Pseudo *

Cut-off

(*) In case that the ellipse approach fails


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• Unusual case, but available

Through an add-on editor

• Example shows the change of

BETA of 2nd-row splitter.


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• Unusual case, but available

Through an add-on editor

• Example shows the change of

THETA of 1st-row splitter.


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• Blade trim or extension

Impeller outer diameter

o on hub

o on shroud

Impeller exit height

Impeller inlet height

• While reserving baseline shape of

Blade angle

Blade thickness

• Useful option for industry design needs


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• Two Different Analysis Methods

SCM (Streamline Curvature Method)

o Also called Velocity Gradient Method

o Sove the velocity gradient equation (inviscid) along

each quasi-orthogonal to streamlines from inlet to exit

FEM (Finite Element Method)

o Subsonic stream-function Poisson equation (inviscid)

o Adler & Krimerman’s H-S stream surface approach

Ideal gas or incompressible fluid for both methods

Note : Just for illustration to show capabilities of two-row splitters with real gas


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Streamlines after

solution converges

Again, just for illustration to show capabilities of two-row splitters with real gas


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Streamlines after

solution converges

The FEM program is a part of my

Ph.D. thesis achievements (1992).

Streamlines after

solution converges



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• A single blade row

• Compressible fluid

Ideal gas

Real gas

• Incompressible fluid

• Turbulent viscous body forces

• No rotor tip clearance

• Multi-grid convergence

• Structured grids

• Effective tool to check aero designs



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• Example using FreeCAD

Part environment

Open > Blade3D.STL

Part > Creat shape from mesh

Blade3D001 solid

with spanwise extensions


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• Tangential Lean

Edit stacking curve

Mostly axial blades


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• Meridional Sweep

Edit stacking curve

Mostly axial blades


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• Interstage key component

Sample industry design from

a multistage centrifugal chiller

compressor using HFC-134a,

looking a lot problematic in

aerodynamics


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On mid-pitchOn 75% span from hub

Near trailing-edge

Blade loadings on shroud

FEMSCM

FEM

Streamlines

SCM

streamlines

Blade Loading Analysis


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• CFD inputs

• Real gas

• 0 rpm (stationary)


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On mid-pitchOn 75% span from hub

Near trailing-edge

Blade loadings on shroud

Spanwise flow angles

at discharge


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• Conventional water

pump impeller


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Loading

Analysis

FEMSCM

FEM

StreamlinesSCM

streamlines


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• CFD inputs

• Incompressible fluid


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• Time-marching

method using

artificial

compressibility for

incompressible

fluid simulation


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On Shroud

On mid-pitch On mid-span


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• Radial-inflow

turbine rotor with

one-row splitter


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FEM

SCM

FEM

Streamlines

SCM

streamlines

Loading Analysis


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On lower mid-pitch

On 75% span from hub

Secondary flows

near trailing-edge

On shroud

• CFD

• Transonic rotor

Convergence


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• NASA CR 72562


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• CFD results


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APPENDIX

BLADE3DR ver.3.3


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• One of Blade3DR default input formats

Blade meanline geometry

Originally the format was from BladeGen (AEA Technology). (now Ansys BladeModeller)

However, for tangential splitter blades, Blade3DR uses a different definition of pitchwise locations.

Full-blade count Number of tangential splitter blades

Full-blade pitch position Number of spans N (Normal thickness) M

T (Tangential thickness)

Normalized span from hub Total number of data

R (Radius) Theta (rad) Z (Axial) T (Thickness)

along camberline

from bladeless-upstream, blade and bladeless-downstream



along camberline


>

>

>

○○ Repeated to Shroud


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End of bladeless-downstream at shroud of full blade

1st-row splitter pitch position(*) Number of spans N (Normal thickness) M




along camberline




along camberline


>

>


>

(*) Relative pitch between two adjacent full blades


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End of bladeless-downstream at shroud of 1st-row splitter blade

2nd-row splitter pitch position(**) Number of spans N (Normal thickness) M




along camberline




along camberline


>

>


>

(**) Relative pitch between full blade and 1st-row splitter blade


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THANKS FOR YOUR INTEREST

Documents

BLADE3DR - turboaerodesign.comBlade three-dimensional profile design and aero/hydrodynamic analysis in turbomachinery ... (by Ansys) Over 12 year-use in personal aero-design tasks