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As part of the Midterm Evaluation of the 2017-2025 Light-duty Vehicle Greenhouse Gas Standards, the U.S. Environmental Protection Agency (EPA) developed simulation models for studying the effectiveness of stop-start technology for reducing CO2 emissions from light-duty vehicles. Stop-start technology is widespread in Europe due to high fuel prices and due to stringent EU CO2 emissions standards beginning in 2012. Stop-start has recently appeared as a standard equipment option on high-volume vehicles like the Chevrolet Malibu, Ford Fusion, Chrysler 200, Jeep Cherokee, and Ram 1500 truck. EPA has included stop-start technology in its assessment of CO2-reducing technologies available for compliance with the standards. Simulation and modeling of this technology requires a suitable model of the battery. The introduction of stop-start has stimulated development of 12-volt battery systems capable of providing the enhanced performance and cycle life durability that it requires.

Low-pressure loop exhaust gas recirculation (LP- EGR) combined with higher compression ratio, is a technology package that has been a focus of research to increase engine thermal efficiency of downsized, turbocharged gasoline direct injection (GDI) engines. Research shows that the addition of LP-EGR reduces the propensity to knock that is experienced at higher compression ratios [1]. To investigate the interaction and compatibility between increased compression ratio and LP-EGR, a 1.6 L Turbocharged GDI engine was modified to run with LP-EGR at a higher compression ratio (12:1 versus 10.5:1) via a piston change. This paper presents the results of the baseline testing on an engine run with a prototype controller and initially tuned to mimic an original equipment manufacturer (OEM) baseline control strategy running on premium fuel (92.8 anti-knock index).

Exhaust emissions of seventeen 2,3,7,8-substituted chlorinated dibenzo-p-dioxin/furan (CDD/F) congeners, tetra-octa CDD/F homologues, twelve WHO 2005 chlorinated biphenyls (CB) congeners, mono-nona CB homologues, and nineteen polycyclic aromatic hydrocarbons (PAHs) from a model year 2008 Cummins ISB engine equipped with aftertreatment including a diesel oxidation catalyst (DOC) and wall flow copper or iron urea selective catalytic reduction filter (SCRF) were investigated. These systems differ from a traditional flow through urea selective catalytic reduction (SCR) catalyst because they place copper or iron catalyst sites in close proximity to filter-trapped particulate matter. These conditions could favor de novo synthesis of dioxins and furans. The results were compared to previously published results of modern diesel engines equipped with a DOC, catalyzed diesel particulate filter (CDPF) and flow through urea SCR catalyst.

As part of the U.S. Environmental Protection Agency’s (EPA’s) continuing assessment of advanced light-duty automotive technologies in support of regulatory and compliance programs, a 2018 Toyota Camry A25A-FKS 4-cylinder, 2.5-liter, naturally aspirated, Atkinson Cycle engine with cooled exhaust gas recirculation (cEGR) was benchmarked. The engine was tested on an engine dynamometer with and without its 8-speed automatic transmission, and with the engine wiring harness tethered to a complete vehicle parked outside of the test cell. Engine and transmission torque, fuel flow, key engine temperatures and pressures, onboard diagnostics (OBD) data, and Controller Area Network (CAN) bus data were recorded. This paper documents the test results under idle, low, medium, and high load engine operation. Motoring torque, wide open throttle (WOT) torque and fuel consumption are measured during transient operation using both EPA Tier 2 and Tier 3 test fuels.

As part of the U.S. Environmental Protection Agency (U.S. EPA) “Midterm Evaluation of Light-duty Vehicle Standards for Model Years 2022-2025 [1]”, the U.S. EPA is evaluating engines and assessing the effectiveness of future engine technologies for reducing CO2 emissions. Such assessments often require significant development time and resources in order to optimize intake and exhaust cam variable valve timing (VVT), exhaust gas recirculation (EGR) flow rates, and compression ratio (CR) changes. Mazda SkyActiv-G spark-ignition (SI) engines were selected by EPA for an internal engine development program based upon their high geometric compression ratio (14:1 in Europe and Japan, 13:1 in North America) and their use of a flexible valve train configuration with electro-mechanical phasing control on the intake camshaft. A one-dimensional GT-Power engine model was calibrated and validated using detailed engine dynamometer test data [2] from 2.0L and 2.5L versions of the SkyActiv-G engine.