Fan System simulation with HyperMesh and AcuSolve solutions

Fan System simulation with HyperMesh and AcuSolve solutions

6th European ALTAIR Technology Conference - April 22-24th, 2013 - Turin, Italy

Manuel Henner, Bruno Demory, Serge Mondon, Ming Ma, Elias Tannoury

Valeo Thermal Systems, France

Youssef BEDDADI

CFD Engineer

VALEO Thermal System, France

[email protected]

mailto:[email protected]

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Fan System developments driven by numerical simulation

Shorten development cycle by virtual prototyping

Offer engineers a reliable tool for design and analysis

Detailed simulation with actual geometry

Willing to develop multi-physics and multi-objectives studies

Standard Valeo Single Fan System

Thermal - Mechanics

Aerodynamics - Acoustics

Rheology

Electronics

Industrial Background An automotive engine cooling fan system

6th European ATC - April 22-24th, 2013 - Turin, Italy

Start

End of the project

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Fan system simulation with ALTAIR Platform Motivations and Objectives


Motivations

Replace current highly integrated numerical methods by ALTAIR methodologies

Communalize tools for several kind of numerical applications (CFD, FEA, etc…)

Reduce license fees with common tools between various R&D teams

Objectives

Investigate solutions offered by ALTAIR for CFD (HyperMesh, HyperView,

AcuSolve)

Test and assess benefit of the platform to implement automation

Evaluate openness of the platform (OpenFoam)

OTHER CFD Softwares

…. AUTO

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Outline

Automated process with ALTAIR Platform

Standard fan simulation process and alternatives

Automation : Batch and scripting

Automated meshing process (HyperMesh)

Pre-processing (Acuconsolve) and solvier (AcuSolve) automation

Automated process for post-processing (HyperView)

Numerical simulations for Fan Systems

Simulation set-up

Comparison between CFD and experimental results

1

2

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Automated process

with ALTAIR Platform


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Automated process with ALTAIR Platform Standard fan simulation process and alternative

Standard Automated Process

CATIA AcuConsole AcuSolve HyperView

HyperMesh OpenFoam ParaView

Alternative Automated process

Automation :

Batch and Scripting


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Batch and scripting in ALTAIR Platform


CATIA

Model.nas

HyperMesh

Mesh.inp

AcuConsole

AcuSolve

HyperView

Performance Prediction

OpenFoam …

Script TCL

Script PY

Batch

Automated process for test rig fan simulation

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Easy scripting and automated volume mesh

Under HyperMesh graphical user interface, activity is recorded in the "command.cmf" file

All the commands recorded and transferred in TCL (Tool Command Language)

Commands can be used without GUI to generate meshes for other geometries with the

same meshing strategy (same grid density, same wall treatment, same volume mesh

domains…)

Batch and Scripting Automated meshing process (HyperMesh)


HyperMesh Mesh

Number of

tetrahedron

87,763,903

Element in INLET 7,133,234

Element in MRF 64,499,930

Element in

OUTLET

16,130,739

Mesh Size (standard parameters to

keep the mesh density constant)

Automated cells extrusions for boundary layer

(same wall treatment for all simulations)

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Volume mesh parameters

Thickness of the first layer, the growth ratio

between 2 tetrahedral layers and the number of

boundary layer.

Openness and automated export

Several types of format possible, including AcuSolve

Easy change for switching solvers, and benchmark different

solutions.

Batch and Scripting Pre-processing (AcuConsole) and solving (AcuSolve)


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Automation process in AcuSolve

AcuSolve commands scripted in Python language

Easy process with only 3 functions:

"usrRunInput“ : Import HyperMesh file

"usrRunHeliceProblem“ : Set the boundary conditions in AcuSolve, solver

parameters, numerical models…

"usrRunAcuSolve" : set the number of processor, generate input file and

launch AcuSolve.

Automation process in HyperView

Same process as HyperMesh with recorded operation


Batch and Scripting Automated process for post-processing (HyperView)

Numerical simulations for

Fan System


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Domain of simulation

Coarse and fine mesh (10 Mo. and 87 Mo. Cells)

K-Omega SA and SST (Menter) turbulence model

HyperMesh and AcuConsole mesh for AcuSolve

RANS simulation


Numerical Simulation for Fan System Simulation set-up

Full outlet domain for

atmospheric conditions

Test rig facility with torque-meter Plenum (mass flow imposed)

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No simplification for tiny details (underhub ribs, tip

clearance, connecting radius)

Cell extrusion at wall boundary (anysotropic layer)

Densification in region of interest


Numerical Simulation for Fan System Meshing strategy with HyperMesh

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Numerical Simulation for Fan System Meshing strategy with HyperMesh

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Numerical Simulation for Fan System AcuSolve simulation

Flow Rate = 2797 m3/h

Flow Rate = 3996 m3/h

800 m3/h 2800 m3/h 4000 m3/h 5200 m3/h

Turbomachinery post-processing


Numerical Simulation for Fan System Open Foam simulation

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Numerical Simulation for Fan System AcuSolve and Open Foam simulation (Coarse mesh)

8,5 millions of tetrahedron

kw SST for turbulence model

Meshing available for different softwares

Good prediction for both solvers

Some improvement to bring at low flow rate

AcuSolve OpenFoam Experiment

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Numerical Simulation for Fan System AcuSolve with AcuConsole or HyperMesh

AcuSolve_Hy permesh AcuSolve_AcuConsole Experiment

87,7 millions of tetrahedron

kw SST for turbulence model

Excellent prediction on torque

Improvement on pressure rise, difference under

investigation

Equivalent results for different mesh types

Conclusions and

perspectives



Conclusions and Perspectives

Achievements

Fan system simulation tested with ALTAIR numerical tools, and a

fully automated process was quickly implemented

HM and HV successfully used for CFD (as for other physics :

mechanics and rheology). Possibility to share common tools

between different R&D teams

Platform easily customizable for connection with other software

(OpenFoam for instance), and comparisons between different

numerical processes has been done

AUTO


Conclusions and Perspectives

Still on progress

Improve meshing process within

small gaps (see tip clearance)

Generalyse best practice for

CFD mesh, with small growth

rate ratio

Further tests to be conducted

with AcuSolve for unsteady

simulation and aeroacoustic

purpose

Thank you for your attention