Combining Data into Complete Engine ALPHA Maps

The Advanced Technology Assessment Branch (ATAB), formerly known as the National Center for Advanced Technology (NCAT), is part of the National Vehicle and Fuel Emissions Laboratory (NVFEL) which assesses the effectiveness of advanced low emission and low fuel consumption technologies for a broad range of key light-duty vehicles, engines, electric motors (eMotor), and transmissions. In support of this work, the ATAB team developed techniques to combine engine operating test data into a set of complete engine maps suitable for use in complete vehicle simulation models and other technical analyses.

These complete engine maps estimate an engine’s fuel consumption over its complete operating range spanning idle and motoring, wide-open-throttle and a predefined redline speed. For each engine analyzed, ATAB uses an in-house modeling tool to combine engine test data from benchmarking tests and/or other sources like technical papers and conference presentations into consistent, publishable, complete engine maps.

Following EPA’s commitment to transparency, ATAB is providing access to the complete engine maps for use in other models, technical analyses, and publications. The files below contain images of complete engine maps, tabular data in a spreadsheet file corresponding to the complete engine map images, a document describing the process for combining the data for the maps, and the Matlab input file ATAB uses in its vehicle simulation model. Please use the citation included in each document when referencing any of these documents.

Sample BSFC Complete Engine Map — **Sample Complete Engine Map for Fuel Consumption (BSFC)**

For more information on ATAB's process for constructing complete engine maps for use in complete vehicle simulation models like ALPHA, see:

SAE 2018-01-1412 Constructing Engine Maps - Presentation at the April 2018 World Congress (pdf) (3.42 MB, April 2018)

For more information on benchmarking and the associated test data packages, see:

Benchmarking Advanced Low Emission Light-Duty Vehicle Technology

Combining Data into Complete Engine ALPHA Maps

Complete Engine "ALPHA Maps" (based on benchmarking data)

Complete Engine "ALPHA Maps" (based on modeled, published or simulation data)

Vehicle and Fuel Emissions Testing

Combining Data into Complete Engine ALPHA Maps

Complete Engine "ALPHA Maps" (based on benchmarking data)​

Complete Engine "ALPHA Maps" (based on modeled, published or simulation data)

Vehicle and Fuel Emissions Testing

Complete Engine "ALPHA Maps" (based on benchmarking data)