The document discusses using a 1D thermal model to evaluate control set points for dual use heater core (DUHC) and active grill shutter (AGS) technologies, which can improve aerodynamic drag. The modeling aims to analyze how the DUHC provides supplemental engine cooling and enables the AGS to remain closed longer, while also investigating the impact of overlap between the thermostat and AGS set points. The results indicate that active thermal management is needed for these technologies to work together effectively under different operating conditions.

1. Evaluation of control
set points for Dual
Use Heater Core and
AGS using a 1D
transient Thermal
model

2. Topics for discussion
1. What are Dual Use Heater Core (DUHC) and
Active Grill Shutters (AGS) technologies?
2. 1D Powertrain Thermal Model
3. Evaluate control set points of DUHC and AGS
2

3. Active Grill Shutters
AGS
• Shutters in front of the cooling pack that
partially block the airflow from going
through the cooling pack to reduce drag
• “EPA will provide a credit for active aerodynamic
technologies that can demonstrate a reduction
in aerodynamic drag of 3% or more. The credit
will be 0.6 g/mile for cars and 1.0 g/mile for
trucks when the reduction in aerodynamic drag
is around 3%”
3

4. Dual Use Heater Core Technology

5. Dual Use Heater Core Technology – 3 modes of operation
5
AC OFF, Cooling ON
AC ON, Cooling ON
HEAT ON, Cooling ON

6. The Crowded Space – Set Points
6

7. 1D Thermal System Model in Flowmaster
7

8. Effect of DUHC on AGS
Paper # (if applicable) 8

9. Scenario 1 – No overlap
9

10. Scenario 1 – No overlap
Paper # (if applicable) 10

11. Scenario 1 – No overlap
Paper # (if applicable) 11

12. Scenario 2 – Effect of Gap between set-
points
12

13. Scenario 2 – Effect of Gap between set-
points
13

14. Scenario 3 – Increase in AGS activation time
14

15. Scenario 3 – Increase in AGS activation time

16. Take-aways
a) Need Active Thermal Management to make technologies play well together
b) A successful application of 1D engine thermal model to analyze the benefits of complementary
but interfering technologies
c) The DUHC technology provides supplemental cooling to the engine and enables the AGS to
remain closed for longer periods during road load driving conditions. The DUHC also increases
the trailer tow rating of the vehicle by providing additional engine cooling.
d) For lower speeds, the overlap of the thermostat set point with the DUHC and the AGS have
minimal impact on their efficacy as the system is airflow limited.
e) Increasing the AGS duration by moving the AGS shut of temperature to an earlier temperature is a
trade-off between AGS cycling and AGS closure rate
16

17. Computational Sciences Experts Group
>25 yrs of combined expertise in 1D
modeling
Deep expertise on system
modeling
Academic advisors
Industry experts using best COTS
tools
We know 1D tools better than anybody else! Our rapid turn
around of simulation analysis allows you to iterate and create
a robust design.

18. Founder and Principal Investigator
Sudhi Uppuluri has over 16 years of experience in the
simulation industry. He 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.

19. Recent technical publications
Uppuluri, S., Proulx, J., Marovic, B., and Naiknaware, A.,
"Characterizing Thermal Interactions Between
Engine Coolant, Oil and Ambient for an Internal
Combustion Engine," SAE Int. J. Engines 6(2):827-
832, 2013, doi:10.4271/2013-01-0960.
Scott, T., Chang, F., Khandaker, M., and Uppuluri, S.,
"Transient Thermal Modeling of Power Train
Components," SAE Int. J. Passeng. Cars - Mech.
Syst. 5(2):962-973, 2012, doi:10.4271/2012-01-0956.
Uppuluri, S., Computational Sciences Experts Group; Sadek
S. Rahman, Chrysler Group LLC, “Active Transient
Thermal Management for improved Fuel economy”,
2012 SAE Thermal Management System Symposium
Chang, F., Malipeddi, S., Uppuluri, S., and Shapiro, S.,
"Underhood Thermal Management of Off-Highway
Machines Using 1D-Network Simulations," SAE
Technical Paper 2003-01-3405, 2003, doi:10.4271/2003-
01-3405.
Uppuluri, S., Naiknaware, CSEG, LLC,“Evaluation of
Various Engine Control Strategy for Optimal Engine
Thermal Operation”, 2014 SAE World Congress: Oral
Only Talk
Uppuluri, S., CSEG, LLC,“Analysis Led Design and
Industry Trends in 1D Powertrain Simulation”, 2013
SAE World Congress: Oral Only Talk
Uppuluri, S., CSEG, LLC, “Dual use heater core for better
trailer tow rating”, 2013 SAE Thermal Management
System Symposium, Oral Only Talk