 

U.S. Department 										55 Broadway
of Transportation										Cambridge, MA 02142

Research and
Innovative Technology
Administration

Volpe National Transportation Systems Center

July 25, 2011
MEMORANDUM
SUBJECT:	Ex parte meeting with EXA Corporation
FROM:		Maurice Hicks, NHTSA	
TO:		Docket No. NHTSA-2010-0079
This memorandum documents a meeting held on November 30, 2010 between EXA, EPA, and DOT regarding the proposed fuel efficiency and greenhouse gas standards for medium- and heavy-duty vehicles and engines for model years 2014-2018.  The attendees included:
EXA:  Stephen Remondi, Doug Hatfield, and Alex Alajbegovic
EPA: Byron Bunker, Cle Jackson, Arvon Mitcham, Chien Sze, Cheryl Bynum, Rich Zhang, Sam Waltzer, and Angela Cullen   
NHTSA/DOT: Angel Jackson and Maurice Hicks
The following topics were discussed during the meeting:
Background
EXA requested a meeting with EPA and NHTSA to discuss testing approaches for determining the aerodynamics drag coefficient for heavy duty tractors.  
EXA stated that CFD has significant benefits over wind-tunnel testing.  Modeling has superior benefits by not being limited to a 0 degree headwind (Zero Yaw), non-moving wheels (or road conditions) and a closed source environment.  EXA has validated CFD models to several full scale wind tunnels test laboratories used by industry.  During the meeting EXA and the agencies discussed the availability of EXA's models and CFD modeling.
EXA asked the agencies to: 
   a) Re-run GEM model results for baselines used by EPA with CFD results for aerodynamic inputs.
   b) Consider best practices for aerodynamic simulation considering all the tools currently available in the market.  
   c) Consider best practices or approaches to moving models to public domain for validation of model results by industry.
   
   The agencies agreed to consider the above requests.
