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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
USING TEMPLATE DRIVEN CFD TECHNOLOGY
FOR ADVANCED AUTOMOTIVE AND MARINE
APPLICATIONSSean Horgan
Managing Director
80/20 Engineering Ltd
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
USING TEMPLATE DRIVEN CFD TECHNOLOGY FOR
ADVANCED AUTOMOTIVE AND MARINE
APPLICATIONS
• AGENDA – ‘NAFEMS UK - 18th July 2018’
• Brief Company Overview – 80/20 Engineering Ltd
• Democratization – Best Practises in the CFD Process• Template Driven CFD Technology
• Meshing Strategy – Binary Adaptive Tree (BAT)
• Advanced Automotive Applications
• Advanced Marine Application
• Conclusions
• Appendix• Published Papers
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
80/20 Engineering
• The Value 80/20 Engineering delivers:
– Design Engineers need to evaluate many concepts quickly and easily, so need a real alternative to traditional physical testing…
• CFD/CAE tools for Product Development
– Some Flow/Thermal/Structural applications are very complex in nature and often companies just don’t possess the resources and/or competencies to perform in-house simulation….
• High Level Simulation Consultancy
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Some of our Customers
QinetiQ - Delivering Customer Focused Solutions
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Machinery Specific Templates
• Flow, Pressure, Heat, Species, Particles
• Aeration & Cavitation: Non-Condensables / Vapor / Compressibility
• Volume Motion and Deformation: Rotation / Translation / Scaling
• Automated Binary-Tree Mesh & Implicit Matching Across Interfaces (MGI)
• Engineering Output: Points / Integrated Data (Volumes & Surfaces)
A T
em
pla
te S
tru
ctu
re
Pistons Crescent /Gerotor Vane / VDVP
ValvesRolling PistonScroll Compressor
Spur (External) Gear Axial / Centrifugal Progressive Cavity
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
• Multiple moving parts: PD pump, control
valve and dynamic bearing
amplified
Real size
Dhar, S., Afjeh, H., Srinivasan, C., Ranganathan, R. et al., "Transient,
Three Dimensional CFD Model of the Complete Engine Lubrication
System," SAE Int. J. Engines 9(3):2016, doi:10.4271/2016-01-1091.
Location Idle Peak Torque Rated High Idle
Pump Outlet 2.16% 1.23% 5.87% 3.35%
After Cooler 4.64% 0.00% 3.62% 2.76%
After Filter 3.28% -0.54% 3.75% 3.74%
Main Gallery 2.13% -1.85% 2.36% 3.04%
Pressure: Difference between prediction and experiment
Gap amplified
Advanced Automotive Applications
- Lubrication Systems
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
• Multiphase flow transient simulation
with air and engine oil
• Crankshaft, camshaft, complete gear
train, piston motion are modeled
• Intermeshing gear teeth
Advanced Automotive Applications
- Crank Case
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Delivers SPEED
in terms of set-up
and run times
whilst retaining
model DETAIL
Mesh Generation for Template Usage
A Binary Adaptive Tree mesher can mesh very complex
geometries and accept CAD geometry with flaws as illustrated
by the following example:
Binary Adaptive Tree
Combines CARTESIAN
Structured mesh and
unstructured
POLYHEDRAL cells
near complex features
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Advanced Automotive Applications
• Vehicle Template - Front End Air Flow
Objectives
• Perform numerical experiments to replicate wind tunnel testing
• Determine for different vehicle speeds, fan speeds, grille or shutter shapes, structures,
license plate configurations, the air flow rates through the grille, condenser, radiator
and fan modules
• Determine the pressure distribution through air induction system
• Under-hood thermal simulation
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Binary Adaptive Tree Mesh
Shutter Grille Movement
Active Grille Shutters (AGS)
Vehicle Template - Front End Air
Flow
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Velocity & pressure
Front End Flow
Metrics: Model Setup and Run
~ With Simerics-MP: “As is” CAD → Computational run: 2 – 3 hours
~Previous CFD Process: 3 – 5 weeks
~ 50 million cells
~ Run time: ~ 16 hours with one 8-core processor*
* Subsequent Simulations: Starting from previous solution takes 4 hours
~ Previous CFD Process : ~ 16 hours with 64 processors (Benchmarking done by our customer)
Template Driven Advantages
Vehicle Template - Front End Air
Flow
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Vehicle Template - Front End Air
Flow
Car Operating Condition Difference with Experiment [%]
Vehicle 1Speed A 1.5
Speed B 4.3
Vehicle 2Speed A 2.6
Speed B 5.1
Vehicle 3Speed A 2.1
Speed B 1.9
• The Vehicle Template predicted flow through the CRFM (Condenser, Radiator, Fan Module) as compared to wind tunnel experiments.
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Full Vehicle Conjugate Heat Transfer Study
Challenges uniquely handled by Template Driven CFD Technology
❖ Full vehicle Conjugate Heat Transfer with 3D cells inside all solid components.
▪ Extremely Complicated CAD, contains 1000’s of solid components
❖ Quick mesh generation with automatic creation of interface between fluid and solid
components.
❖ All solid temperatures are calculated accounting for all 3 modes of heat transfer :
conduction, convection and radiation.
❖ Mesh adapts to small gaps, holes and captures the small features of the geometry
Underhood Underbody Thermal
Objectives
▪ Problem: Heat transfer is driven by hot exhaust gases flowing through the exhaust system into
the atmopshere
▪ Analysis Goal: Perform full vehicle (under-body and under-hood) thermal conjugate heat transfer
simulation with surface-to-surface radiation
▪ Importance: Understand peak temperatures on solids to ensure material integrity at high
temperatures
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Process
1. CAD Preprocessing 4 (manual)
2. Mesh Generation (87 M cells) 6
3. Model Pre-processing 16 (manual)
4.ARadiation S2S view factor
calculation8
4.B Simulation run (500 iterations) 48
Total6 calendar
days
Man Hours2.5 working
days
Full Vehicle Conjugate Heat Transfer Study: Metrics
Underhood Underbody Thermal
Heat transfer
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Vehicle Driving through a Water Pool Air Induction System
Dirty Side
Clean Side
Model Formulation
Problem: Vehicle drives through a pool of water, at varying speeds
and water pool depths
Analysis Goal: Determine if the air suction to the engine will pull
water to the clean side of the air filter
- Can Vehicle Template Technology replicate water-tunnel test?
Why Important: In off-road vehicles, water fording test is important for
the durability of the engine
Vehicle Water Fording
Water Fording
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Air Induction System
Vehicle Water Fording
Water Fording
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Template Driven Simulation for
Advanced Marine Applications:
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
DTMB 5415 – Validation Study
-1.5
-1.0
-0.5
0.0
0.5
0.0 0.1 0.2 0.3 0.4 0.5T
rim
(d
eg)
Fr
Trim
0
2
4
6
0.0 0.1 0.2 0.3 0.4 0.5
Sin
ka
ge/
Lp
px1
03
SinkageCFD
Experiment
0.003
0.004
0.005
0.006
0.007
0.008
0.0 0.1 0.2 0.3 0.4 0.5
CT
Drag Coefficient CT
Marine Applications –
Displacement Hull Drag, Sinkage
and Trim
‘2017_SNAME_Prediction of Planing Hull Resistance and
Porpoising using a RANS-based CFD Tool’
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Applications –
C-Fury Rib
• A 80/20 Engineering case study illustrating
the capabilities of the Marine Template using
CFD simulation of a C-Fury Rigid Inflatable
Boat (RIB) is now presented.
• This model was run as a two-phase flow
simulation using the Simerics Marine
Template. The model is first accelerated from
0 to 8 knots and then from 8 to 15 knots.
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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Template –
Geometry
The geometry of the RIB was supplied by C-Fury as a Rhino .3dm file. This was
read directly into our SpaceClaim model preparation tool.
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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Template –
Model Preparation• The surface geometry of the hull needed minor repair
• converted to a solid by adding a deck surface.
• The hull geometry was then combined with the hydrofoil surfaces.
• The surfaces were also named to be recognised in Simerics.
• STL files were then produced to transfer to Simerics.
• These files could have been produced directly from Rhino.
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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Template
- Meshing
The .stl file of the hull was read into Simerics
MP and the surfaces created were selected
for the Marine Mesh Template. A medium
resolution mesh refinement setting was
selected and the minimum cell size was
reduced in order to capture the fine details in
the hull shape.
The meshing template also requests the
movement direction and the centre of gravity
so it can determine a suitable mesh pattern.
The size of the domain around the vessel can
also be specified. Most of the domain size
and mesh size settings can be left to default if
the user is uncertain of what values to use.
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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine
Template
- Meshing
23
The resultant mesh
contained 4,653,126
cells with 15,607,078
faces. The template
ensures that this is
concentrated around the
hull and in the wake
region as illustrated
here.
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Template - Set-up
For this type of two phase flow
simulation the solution parameters are
also entered via the marine template.
The additional quantities required at
this stage are the target velocity and
the mass of the vessel. The other
quantities shown in the panel on the
right can also be adjusted.
For the initial case the target velocity
was set to 8 knots with a ramp up time
of 1 second. Once this initial
simulation was completed the velocity
was then increased to 15 knots and
the solution was restarted.
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NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Marine Template - Solution
• The solution is run as a transient. All the controls are set by the template described on the previous slide.
• The first stage of the solution, to accelerate the Rib to 8 knots, took approximately 14 hours to run on a Dell Precision 7520 laptop with a seventh generation Intel i7 processor.
• The second stage (from 8 to 15 knots) took longer to settle so took approximately 24 hours to run the transient to a total of 12 seconds.
25
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
0 to 8 Knot Transient26
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
8 to 15 Knot Transient27
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
8 to 15 Knot Transient28
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
8 to 15 Knot Transient29
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
CONCLUSIONS
• Summary:
– Advanced Template Driven CFD Technology
Presented
• Fluid Machinery Background
• Expanding Automotive Applications
• Marine Applications
• Thank you for your time
• Mobile: 07879 432669
• Office Tel: 01494 616020
• www.8020engineering.com
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
Appendix - Published Papers
Simerics Actively Participates in Academic Activity
NAFEMS World Congress 2015 | 21-24 June | San Diego | California | USANAFEMS UK Conference 2018 | 17-18 July| Milton-Keynes | UK
80/20 Engineering
•The Pareto Principle, often called "The 80/20 Rule", means that in
anything, the few (20 percent) is usually responsible for the many (80
percent).
•Application to the Engineering ‘Simulation’ Process
– 80% of business value delivered by 20% of analysis resources
deployed for simulation.
• Critical that simulation resources are used in an optimum
way
•Focus on Product Development
– 80% of product performance, or project success is defined by 20%
of the development life-cycle.
• Critical that performance information is available at the
earliest opportunity.