Energy factors for flexible fuel engines and vehicles operating with gasoline-ethanol blends

Toshizaemom Noce, Rafael Rocha da Silva, Rafael Morais, Luis Carlos Monteiro Sales, Sérgio de Morais Hanriot, José Ricardo Sodré*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


This work investigates the energy factors for fuel conversion from the analysis of brake specific fuel consumption (BSFC) maps of a sample of 15 engines, representative of 75% of current models available in the Brazilian market. The method also employs the engine driving patterns of power output versus crankshaft speed obtained from bench dynamometer tests. The energy factors obtained from the engine analysis was validated against experiments carried out with two production vehicles in laboratory tests following the 1975 US Federal Test Procedure (FTP-75) procedure and road tests following 16 different urban and highway routes. The fuels used in the tests were hydrous ethanol (E100, 6 v/v % water) and a blend of 22 v/v % anhydrous ethanol and 78 v/v % gasoline (E22). The energy factors found from the 3D engine BSFC map analysis were higher than those obtained from the Willans line, currently adopted as a standard, by 52% for E22 and 57% for E100. The results from the 3D engine BFSC maps and the first vehicle following the FTP-75 cycle and 15 road routes were similar, also close to the results from the second vehicle, qualifying them to be representative of modern flexible fuel spark ignition engines and vehicles.

Original languageEnglish
Pages (from-to)368-374
Number of pages7
JournalTransportation Research Part D: Transport and Environment
Early online date20 Sept 2018
Publication statusPublished - 1 Dec 2018


  • Energy factor
  • Ethanol
  • Spark ignition engines
  • Specific fuel consumption
  • Willans line


Dive into the research topics of 'Energy factors for flexible fuel engines and vehicles operating with gasoline-ethanol blends'. Together they form a unique fingerprint.

Cite this