Search Results

Fuel economy (FE) and greenhouse gas (GHG) emissions measured via chassis testing under laboratory conditions were never intended to represent the wide range of real-world driving conditions that are experienced during a vehicle's lifetime. Comprehensive real-world information is needed to better assess US FE label adjustments, determine off-cycle credits for FE standards, and forecast real-world driving behavior, fuel consumption, and CO2 emissions. This paper explores a cost effective method to collect in-use fuel consumption data using the on-board diagnostics (OBD) data stream in light-duty vehicles (LDVs). The accuracy of fuel consumption calculated from the OBD data was analyzed in two ways. First, fuel rates calculated from standard OBD Parameter IDs (PIDs) were compared with fuel rate estimates based on enhanced PID (OEM fuel injector fuel rate) data in two different vehicles.

The cost of meeting standards for conventional pollutant emissions is a perennial bone of contention in arguments over vehicle emission regulations. The public health benefits of the most stringent standards have been repeatedly and conclusively demonstrated, and the control technologies are readily available. Nevertheless, countries with the largest vehicle markets worldwide differ greatly in the rates at which they are willing to adopt the most stringent emission standards-and some of those whose populations would benefit most lag furthest behind the best achievable standards. Among the reasons often given for delaying the implementation of stricter standards is the extra cost added to the vehicle by the emission control system. As part of a two series paper, this paper addresses the cost of diesel light-duty emission control technology by regulatory level, from early stages to upcoming levels, and presents a comparison with gasoline emission control technologies.

The cost of meeting standards for conventional pollutant emissions is a perennial bone of contention in arguments over vehicle emission regulations. The public health benefits of the most stringent standards have been repeatedly and conclusively demonstrated, and the control technologies are readily available. Nevertheless, countries with the largest vehicle markets worldwide differ greatly in the rates at which they are willing to adopt the most stringent emission standards-and some of those whose populations would benefit most lag furthest behind. Among the reasons often given for delaying the implementation of stricter standards is the extra cost added to the vehicle by the emission control system. This two-part series paper assesses separately the cost of emission control technologies for gasoline and diesel light duty vehicles. In part one, the paper addresses the cost of gasoline light-duty emission control technology by regulatory level, from early stages to upcoming levels.

The large fleet share and rapid growth of two and three wheeler vehicles in India means that careful attention must be paid to reducing emissions and fuel consumption from these vehicles. Emission standards and emission control technologies employed in passenger vehicles have not fully migrated to two and three wheelers. Fuel economy standards and advanced fuel efficient technologies, which offer great potential for reducing sector energy consumption, have also not been implemented for this important mode of transportation. This paper contains an overview of the engine technology changes and after-treatment systems being employed by Indian two and three-wheeler manufacturers to meet the Bharat Stage-III emission standards. An assessment of technical options to meet future emission standards is discussed. Adoption of evaporative emissions and on-board diagnostic systems technologies are discussed as well.

The key to overcoming Low Temperature Combustion (LTC) load range limitations is based on suitable control over the thermo-chemical properties of the in-cylinder charge. The proposed alternative to achieve the required control of LTC is the use of two separate fuel streams to regulate timing and heat release at specific operational points, where the secondary fuel, with different autoignition characteristics, is a reformed product of the primary fuel in the tank. It is proposed in this paper that the secondary fuel is produced using Thermo-Chemical Recuperation (TCR) with steam/fuel reforming. The steam/fuel mixture is heated by sensible heat from the engine exhaust gases in the recuperative reformer, where the original hydrocarbon reacts with water to form a hydrogen rich gas mixture. An equilibrium model developed by Gas Technology Institute (GTI) for n-heptane steam reforming was applied to estimate reformed fuel composition at different reforming temperatures.