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Contrails and aircraft-induced cirrus clouds are reputed being the largest components of aviation-induced global warming, even greater than carbon dioxide (CO2) exhaust emissions by aircraft. This article presents a contrail model algorithm specifically developed to be integrated within a multi-objective flight trajectory optimization software framework. The purpose of the algorithm is to supply to the optimizer a measure of the estimated radiative forcing from the contrails generated by the aircraft while flying a specific trajectory. In order to determine the precise measure, a comprehensive model is employed exploiting the Schmidt-Appleman criterion and ice-supersaturation regions. Additional parameters such as the solar zenith angle, contrail lifetime and spread are also considered.

Onboard diagnostic regulations require performance monitoring of diesel particulate filters used in vehicle aftertreatment systems. Delphi has developed a particulate matter (PM) sensor to perform this function. The objective of this sensor is to monitor the soot (PM) concentration in the exhaust downstream of the diesel particulate filter which provides a means to calculate filter efficiency. The particulate matter sensor monitors the deposition of soot on its internal sensing element by measuring the resistance of the deposit. Correlations are established between the soot resistance and soot mass deposited on the sensing element. Currently, the sensor provides the time interval between sensor regeneration cycles, which, with the knowledge of the exhaust gas flow parameters, is correlated to the average soot concentration.

Dual-monolith catalyst systems containing Pd/Rh three-way catalysts (TWCs) provide effective emission solutions for LEV2/Bin 5 and Bin 4 close-coupled applications at low PGM loadings. These systems combine washcoat technology and PGM distribution for front and rear catalysts resulting in optimal hydrocarbon and NOx light-off and transient NOx control. The dual-catalyst [Pd/Rh + Pd/Rh] systems are characterized as a function of Pd-Rh content, PGM location, and catalyst technology for 4-cyl [close-coupled + underfloor] systems and 6-cyl close-coupled applications. The current Pd/Rh dual-catalyst converters significantly reduce NOx emissions compared to earlier [Pd + Pt/Rh] or [Pd + Pd/Rh] LEV/ULEV systems by utilizing uniform Rh distribution and new OSC materials. These new design strategies particularly impact NOx performance, especially during transient A/F excursions.

Delphi Automotive Systems and BMW are jointly developing Solid Oxide Fuel Cell (SOFC) technology for application in the transportation industry primarily as an on-board Auxiliary Power Unit (APU). In the first application of this joint program, the APU will be used to power an electric air conditioning system without the need for operating the vehicle engine. The SOFC based APU technology has the potential to provide a paradigm shift in the supply of electric power for passenger cars. Furthermore, by supplementing the conventional fuel with reformate in the internal combustion engine, extremely low emissions and high system efficiencies are possible. This is consistent with the increasing power demands in automobiles in the new era of more comfort and safety along with environmental friendliness. Delphi Automotive Systems and BMW were successful in demonstrating an Auxiliary Power Unit (APU) based on Solid Oxide Fuel Cell (SOFC) technology in February, 2001.

Performance of two types of NOx adsorber catalysts, one based on Ba and the other based on Ba with alkali metals, was compared fresh and after thermal aging. Incorporation of sodium(Na), potassium(K) and cesium(Cs) into NOx adsorber washcoat containing barium significantly increases the NOx conversions in the temperature range of 350-600°C over that of the alkali metal free NOx adsorber catalysts. NOx performance benefit and HC performance penalty were observed on both engine dynamometer and vehicle tests for the “Ba+alkali metals” NOx adsorber catalysts. “Ba+alkali metals” NOx adsorber catalysts also demonstrate superior sulfur resistance with better NOx performance after repeated sulfur poisonings and desulfations over the “Ba based” NOx adsorber catalysts.

California Ultra Low Emission Vehicle (ULEV) standards call for a significant reduction in the amount of harmful gases that enter the environment from vehicle exhaust. The Electrically Heated Catalyst (EHC) is a possible solution to reduce emissions. A competitive analysis benchmarking study was completed in order to find an optimum EHC design that will perform to ULEV standards. Four suppliers submitted samples and the EHC designs were rigorously tested for temperature, pressure drop, and emissions performance while being aged at different levels.

In vehicular mobility context, it is extremely important for the environmental sustainability that the available energy will be used as efficiently as possible, both in the use of internal combustion engines (ICE) as powertrain, as well in the application of Hybrid and Electric Vehicle Motors (HEV/EV). In this comparison, ICE has a lower efficiency when compared to electric motors, wasting much of the potential energy of the fuel in form of heat and noise. On the other hand, the electric vehicles face limitation in autonomy and recharge time, demanding for a more efficient use of energy stored in batteries. This study aims to present emerging technologies for reuse of energy within the automotive context, originally known as “Energy Harvesting” and “Renewable Energies”.

It is well known that hydrocarbon reduction during a cold start is a major issue in achieving ultra low emissions standards. This paper describes one of the possible approaches for reducing the cold-start hydrocarbon emissions by using a fast “light-off” planar oxygen sensor. The goal of this study was to verify the operation characteristics of Delphi's fast “light-off” planar oxygen sensor's (INTELLEK OSP) operating characteristics and the closed-loop performance for achieving improved hydrocarbon control for stringent emission standards. Tests were conducted in open-loop and closed-loop mode under steady and transient conditions using a 1996 model year 2.4-liter DOHC in-line 4-cylinder engine with a close-coupled catalytic converter. Overall performance of the OSP showed relatively quick reaction time to reach the operating temperature.

Dual-brick catalyst systems containing Pd-only catalysts followed by Pt/Rh three-way catalysts (TWCs) are effective emission solutions for both close-coupled and underfloor LEV/ULEV applications due to optimal hydrocarbon light-off, NOx control, and balance of precious metal (PGM) usage. Dual-brick [Pd +Pt/Rh] systems on 3.8L V-6 LEV-calibrated vehicles were characterized as a function of PGM loading, catalyst technology, converter volumes, and substrate cell density. While hydrocarbon emissions improve with increasing Pd loading, decreasing the front catalyst volume at constant Pd content (resulting in higher Pd density) improved light-off emissions. Use of 600cpsi substrates improved underfloor NMHC emissions on a 3.8L vehicle by ∼ 6-10mg/mi compared to 400cpsi catalysts, and thus allowing reduction of catalyst volume while achieving ULEV emission levels without air addition.

Proposed vehicle emissions regulations for the near future have prompted automotive manufactures and component suppliers to focus heavily on developing more efficient exhaust aftertreatment devices to lower emissions from spark and compression ignition engines. One of the primary pollutants from lean-burn engines, especially from diesels, are oxides of nitrogen (NOx). Current three-way catalytic converters will not have adequate performance to meet future emission reduction requirements. Therefore, there is a need for researchers and engineers to develop efficient exhaust aftertreatment devices that will reduce NOx emissions from lean-burn engines. These devices must have very high conversion of NOx gases, be unaffected by exhaust-gas impurity such as sulfur, and have minimal impact on vehicle operations and fuel economy. An effective technology for NOx control that is currently receiving a lot of attention is a non-thermal plasma system.

With new legislation and federal regulation for vehicle emission levels, automotive and truck manufacturers have been prompted to focus on emission control technologies that limit the level of exhaust pollutants. One of the primary pollutants, especially from diesel engines, is oxides of nitrogen (NOx). One possible solution to this pollution challenge is to design a more efficient internal combustion engine, which would require better engine operating parameter controls. However, there are limitations associated with such tight engine management. This need has led researchers and engineers to focus on the development of exhaust aftertreatment devices that will reduce NOx emissions with current diesel engines. An optimum aftertreatment device must be unaffected by exhaust-gas impurity poisoning such as sulfur products, and must have minimal impact on vehicle operations and fuel economy.

With ever more stringent CO2 emissions mandates, many automobile manufacturers are seeking the fuel economy benefits of diesel and lean-burn gasoline engines. At the same time the emissions standards that diesel and gasoline engines will have to meet in the next decade continue to reduce. Proposed solutions for meeting the stringent emissions standards all appear to have limitations, such as propensities to poisoning from sulfur, narrow operating temperature windows, and requirements for controls that give rapid rich excursions. Non-thermal plasma-catalyst systems have shown good performance in bench testing while being largely unaffected by these same issues. A two-stage system with a unique non-thermal plasma reactor combined with a zeolite-based catalyst has been constructed and shown to work over a wide temperature range.

This paper presents the conceptual design of a new low-cost measurement system for the determination of pollutant concentrations associated with aircraft operations. The proposed system employs Light Detection and Ranging (LIDAR) and passive electro-optics equipment installed in two non-collocated components. The source component consists of a tuneable small-size and low-cost/weight LIDAR emitter, which can be installed either on airborne or ground-based autonomous vehicles, or in fixed surface installations. The sensor component includes a target surface calibrated for reflectance and passive electro-optics equipment calibrated for radiance, both installed on an adjustable support. The proposed bistatic system determines the column-averaged molecular and aerosol pollutant concentrations along the LIDAR beam by measuring the cumulative absorption and scattering phenomena along the optical slant range.

With the purpose of reducing emission level while maintaining the high torque character of diesel engine, various solutions have been proposed by researchers over the world. One of the most attractive methods is to use dual fuel technique with premixed gaseous fuel ignited by a relatively small amount of diesel. In this study, Methane (CH4), which is the main component of natural gas, was premixed with intake air and used as the main fuel, and diesel fuel was used as ignition source to initiate the combustion. By varying the proportion of diesel and CH4, the combustion and emissions characteristics of the dual fuel (diesel/CH4) combustion system were investigated. Different cases of CFD studies with various concentration of CH4 were carried out. A validated 3D quarter chamber model of a single cylinder engine (diesel fuel only) generated by using AVL Fire ESE was modified into dual fuel mode in this study.

Exhaust heat recovery systems are used to make use of otherwise wasted heat from a car engine. The purpose of exhaust heat recovery systems is to reduce the fuel consumption of the car and consequently reduce CO2 emissions. The unique system design described herein utilises thermoelectric generators (TEGs) and heat pipes with its key advantage being it is a passive solid state design. The use of these components creates a few design constraints. For example, both the TEGs and heat pipes have operating temperature limitations. In this paper, a naphthalene heat pipe preheat exchanger is proposed to deal with this problem. Exhaust conditions measured from a representative spark ignition engine were used in a numerical simulation to predict the performance of the exhaust heat recovery system. If 8 modules are used and the engine is producing 8kW of mechanical power, the system is predicted to produce 53.75W of electrical power.

A double dielectric barrier discharge reactor driven by an alternating voltage is a relatively simple approach to promote oxidation of NO to NO2 for subsequent reduction in a catalyst bed. The chemical performance of such a non-thermal plasma reactor is determined by its current and electric field behavior in the gap, and by the fraction of the current carried by electrons, because the key reactants which initiate the NO oxidation and accompanying chemical changes are produced there, mostly by electron impact. We have tried to determine by models and experiments the bounds on performance of double dielectric barrier reactors and guidelines for optimization. Models reported here predict chemical results from time-resolved applied voltage and series sense capacitor data.

This paper describes recent progress in our program to develop a gasoline-fueled vehicle with an on-board reformer to provide near-zero tailpipe emissions. An on-board reformer converts gasoline (or another hydrocarbon-containing fuel) into reformate, containing hydrogen (H2) and carbon monoxide (CO). Reformate has very wide combustion limits to enable SI engine operation under very dilute conditions (either ultra-lean or with heavy exhaust gas recirculation (EGR) concentrations). In previous publications, we have presented engine dynamometer results showing very low emissions with bottled reformate. This paper shows results from an engine linked to an experimental, fast start-up reformer. We present both performance data for the reformer as well as engine emissions and performance results. Program results continue to show an on-board reforming system to be an attractive option for providing near-zero tailpipe emissions to meet low emission standards.