2. Computational Sciences Experts Group
We don’t sell software. We bring our modeling expertise
and make your CAE software do
advanced stuff.
The stuff you bought the
software to do to begin with.
3. CSEG Services
1. Calibrate: 2. Integrate:
We integrate various
We build accurate
simulation tools for a
simulation models and
specific problem to
calibrate them with test
reduce error and
data
improve accuracy
4. Optimize: 3. Interface:
We build optimization We build simplified
tools or integrate with interfaces for complex
existing ones to models to enable faster
optimize key variables and wider use of
in the system simulation models
4. The Speaker
Sudhi Uppuluri, Principal Investigator
Sudhi has over 14 years of experience in the
simulation industry. He worked as a consulting
engineer and sales manager at Flowmaster USA for
8 years where he worked on various advanced fluid
system modeling in Automotive and Aerospace fields.
He has various technical publications on related
subjects in SAE and AIAA journals. He holds a
Masters in Aerospace Engineering from the
University of Illinois at Urbana-Champaign and a
Certificate in Strategy and Innovation from the MIT
Sloan School of business.
Email: Sudhi.Uppuluri@cseg.us
Full Profile on Linked in: Sudhindra Uppuluri
5. Topics
a) Engine thermal management challenges
b) Traditional cooling system – Key
considerations
c) HEV, EV specific challenges
d) Bigger picture
e) Roadmap
6. Why is Engine Thermal Management
important?
• Cold Engine = Bad
Fuel Economy Frictional
losses reduce
– Incomplete as engine
combustion warms up
– Increased thermal
losses through the
combustion
chamber walls
– Increased friction
losses with the
increase of the
lubricant oil
viscosity.
Referemce: 2000-01-0299
Warm-Up of a D.I. Diesel Engine:
Experiment and Modeling
L. Jarrier and J. C. Champoussin Ecole Centrale de LYON R.
Yu Renault D.R. D. Gentile University of Versailles
7. Challenges for Engine Thermal
Management
Tighter packaging!
Right size component.
Fuel economy sensitive to temperatures!
Engines are getting
smaller More components
need cooling
Not enough heat Electric components
for satisfactory (Battery, inverter etc.)
heater core need to be cooled
performance. Overheating and fires!
Cabin comfort is
compromised!
8. Challenges – Simulating Engine
Thermal systems
Requires Responsibility fragmented
expertise across across the organization
multiple
subjects
Why Engine Model is
Thermal data
Management hungry
Modeling is
Experimental hard!
procedures are Data not
for validating Majority of readily
designs, not data is available
models steady-
state
10. Steady State Flow Model – Starting
point
Geometry and
Fairly Straightforward – Based on
component supplier data
11. Key issue #1: Model necessary
thermal interactions between sub-
systems
Requires integration of all key thermal fluid systems –
Cooling, AC, Engine Oil, Transmission Oil, Front-End
cooling pack
12. Key Issue #2: Get Heat additions
correct
Combustion heat = Energy from Fuel &Air mixture – Exhaust Energy – Work (indicated Po
+Qcomb
+QFric
Frictional heat = Indicated Power –Pumping Work
13. Key issue #2a: Get heat losses
correct
Heat Loss to
the ambient
(Conduction +
Natural convection
Heat absorbed + Forced
by the mass convection)
Heat Loss to
the Coolant
Heat Loss to
the Oil
14. Where the heat goes during warm-
up
SAE 2000-01-0299
Warm-Up of a D.I. Diesel Engine: Experiment and Modeling
L. Jarrier and J. C. Champoussin Ecole Centrale de LYON R. Yu Renault D.R. D. Gentile University of Versailles
15. Key issue #3: Modeling Thermal
inertia right
Thermal inertia
option 1 – Cylinder head
Capturing minimum
number of masses to
predict warm-up Coolant Circuit
Include the correct Upper block
volume of fluid.
(Thermal inertia of the Lower block
fluid)
Engine Oil Circuit Sump
16. Key issue #3: Modeling Thermal
inertia right
• Thermal
inertia option
2 – Capturing every
heat transfer path
(more components =
more data required)
Reference: SAE paper 910302, Kaplan and Heywood.
17. Key issue #3: Modeling Thermal
inertia right
• Thermal
inertia option
3 – Capturing every
heat transfer path
(more components =
more data required)
Reference: SAE paper 960073, Bohac, Baker and Assanis.
18. Where the heat goes during warm-
up
Reference: SAE paper 931153, Shayler et al.
19. Key Factors in warm-up
Heat distribution and loss
Thermal Inertia
20. Key Issue #5: Include a dynamic
coolant Thermostat
• Include dynamic model
– Lift vs temperature
(supplier data, left)
– Test data (below)
– Dynamic mechanical model
21. HEV, EV specific challenges
• Li-ion battery cooling is
• more than just an
additional isolated
• cooling task. It requires
• complex thermal
management and
• careful analysis
• Reference: Behr Technical Press Day 2009;
http://www.behr.de/internet/behrmm.nsf/lupgraphics/Behr_
Thermomanagement_TPT09_E.pdf/$file/Behr_Thermomanage
ment_TPT09_E.pdf
22. HEV Additions – front-end cooling
pack
Segmented heat
exchanger analysis to
enable higher fidelity
cooling pack analysis
• Reference: Behr Technical Press Day 2009;
http://www.behr.de/internet/behrmm.nsf/lupgraphics/Behr_
Thermomanagement_TPT09_E.pdf/$file/Behr_Thermomanage
ment_TPT09_E.pdf
23. Improving fuel economy
5
Accurate
standard model
4.5 with coldstart friction engine
numerical model
with coldstart friction transmission
with coldstart friction eng&trans
4
of Engine Thermal
fuel consumption [kg/s]
Management 3.5
Predictive fuel
3
economy and Engine
2.5
thermal model 2
Evaluate a wide
1.5
array of solutions to 1
improve fuel economy
and added HEV cooling
0.5
challenges 0
0 50 100 150 200 250 300
t [s]
For 600s simulation, starting from 40degC:
standard model 0.4347 kg
with coldstart friction engine 0.4557 kg +4.8%
with coldstart friction transmission 0.4543 kg +4.5%
with coldstart friction engine & transm. 0.4799 kg +10.4%
24. Thermo-Fluid System Analysis
Roadmap
Deliver
• Fuel economy benefits with
effective thermal management
strategy
• Predictive analytical capability
reducing prototype costs
Collaborate
Value
• Provide trade-off across multiple systems (cooling,
Lubrication, AC, transmission, front-end cooling
pack)
• Value-added partnership with customers and
suppliers
Analysis basics in place.
Are we here? Troubleshoot and Optimize
• Transient behavior of system providing insight
into delivering a robust design
• Optimization of system variables
Ensure accurate system operation
• Flow balancing to ensure all components have
adequate flow
• Evaluate individual component performance
Functionality
25. Topics covered
a) Engine thermal management challenges
b) Traditional cooling system – Key
considerations
c) HEV, EV specific challenges
d) Bigger picture
e) Roadmap
26. FURTHER Sudhi Uppuluri has over 14 years of
experience in the simulation industry. He
DISCUSSION
worked as a consulting engineer and sales
manager at Flowmaster USA for 8 years
.He has various technical publications on
related subjects in SAE and AIAA journals.
He holds a Masters in Aerospace
Engineering from the University of Illinois
at Urbana-Champaign and a Certificate
in Strategy and Innovation from the MIT
Sloan School of business.
Contact:
Sudhi Uppuluri
Principal Investigator
Sudhi.uppuluri@cseg.us
(781) 640 2329
www.cseg.us