Fuel Economy Improvements and NOx Reduction by Reduction of Parasitic Losses: Effect of Engine Design

Abstract

Reducing aerodynamic drag and tire rolling resistance in trucks using cooled EGR engines meeting EPA 2004 emissions standards has been observed to result in increases in fuel economy and decreases in NOx emissions. We report here on tests conducted using vehicles equipped a non-EGR engine meeting EPA 2004 emission standards and an electronicallycontrolled engine meeting EPA 1998 emissions standards. The effects of trailer fairings and single-wide tires on fuel economy and NOx emissions were tested using SAE test procedure J1321. NOx emissions were measured using a portable emissions monitoring system (PEMS). Fuel consumption was estimated by a carbon balance on PEMS output and by the gravimetric method specified by test procedure J1321. Fuel consumption decreased and fuel economy increased by a maximum of about 10 percent, and NOx emissions decreased by a maximum of 20 percent relative to baseline. This compares with NOx reductions of up to 45 percent reported in the earlier test on the cooled EGR engine. The reduction in power requirements in the current test did not result in a corresponding reduction in brake specific NOx emissions, as it did in the earlier test. These results provide further evidence that reducing parasitic losses in heavy-duty highway vehicles will not only reduce fuel consumption and greenhouse gas emissions, but will also provide NOx reductions that pay for themselves through reduced fuel use.

Do Changes in Temperature and Inflation Pressure Affect Rolling Resistance during Road and Track Testing for Fuel Economy of Class 8 Tractor-Trailers?

“…The U.S. Environmental Protection Agency (EPA) has been testing the performance of low rolling resistance tires and aerodynamic fairings in order to evaluate their potential to reduce fuel consumption and emissions of greenhouse gas and criteria pollutants [1,2,3]. Tests have been conducted using the SAE J1321 test method [4].…”

An examination of a voluntary policy model to effect behavioral change and influence interactions and decision making in the freight sector

“…EPA SmartWay also influences and informs the market on equipment and technology upgrades in other ways that has contributed to a more advanced national trucking fleet. The partnership has published peer-reviewed papers and technical fact sheets that describe the testing protocols, performance criteria and test data that it uses to ensure that vehicles, equipment and technologies will help fleets improve their efficiency and reduce emissions (Bachman et al, 2005; Bachman et al, 2006; Bachman et al, 2014; Waltzer et al, 2015). Through its verification and designation programs, and by actively contributing to trade, industry and academic journals EPA SmartWay has advanced the freight industry’s understanding of the benefits of technology adoption and the economic value of sustainability.…”

Real Driving Emissions – Vehicle Tests in Variable Terrain

“…where: j -harmful compound, for which an emission factor has been specified, Ereal,j -emission of the chosen pollutant obtained in real driving conditions [g/km], Enorm,j -road emissions according to the exhaust emission standards [g/km] (based on [9]).…”

“…The research carried out at Poznan University of Technology with the use of this method attempts to answer questions regarding the exhaust emissions, their variability and relation to the engine and vehicle operating parameters [5][6][7]. The paper presents several vehicles investigated for exhaust emissions under actual traffic conditions -RDE (Real Driving Emissions) [8][9][10].…”