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Measurement procedures for the legal limitation of emissions from heavy duty engines should adequately reflect the actual use of such engines in practice. Equally important is the possibility to monitor the emision performance of certified engines on the market. This paper gives a short overview of the experiences with the Dutch in-use compliance program for HD vehicles. The results indicate that such a monitoring of the existing fleet is of great importance for the national authorities. This means that any measurement procedure envisaged for legislation purposes should take account of the requirement of relatively easy monitoring of the emission behaviour in service just as much as the requirement of adequate simulation of practical vehicle operation.

Vehicle emissions are one of a number of environmental problems in urban areas which have received much public attention for nearly twenty years [1] and are still now very topical. In particular, public opinion in Europe is opposed to the visible smoke, ‘black’ from diesel engines and ‘blue’ from oil burning petrol and diesel engines. This paper describes the use of 90 degree backscatter measurements to determine and measure ‘black’ and ‘blue’ smoke effects in an in-service environment, i.e. no dynamometer or loaded cycle testing. The measurements are compared to opacity measurements and the advantages and disadvantages discussed. White smoke effects will not be addressed in this paper.

The introduction of the three way catalyst (TWC) has considerably reduced emissions from gasoline fueled cars. Most of the pollutants from these cars are emitted during the cold start period. At lower ambient temperatures (below +20°C), as in the Northern part of Europe, these emissions increase considerably. In Sweden engine block heaters, mostly in combination with compartment heaters, are often used to increase the driver's comfort. The increased engine temperature also reduces emissions. Block heaters are also suitable for after-market installations, and can thus reduce emissions from in-use cars. This paper reports the investigations of the effects of a block heater on emissions and fuel consumption. It was decided to conduct tests on three types of light duty vehicles: cars with TWC, cars without TWC, and one car with very low emissions (i.e. TLEV). The cars were tested according to the FTP-75 test procedure at +22, +5 and -15°C ambient temperature.

Cycle-to-cycle changes in diesel exhaust gas emissions were investigated under two transient operation patterns: One, “an interval step decreasing and increasing load”, where the fuel amount is rapidly decreased from high to low loads, and after an interval, Δtint the fuel amount is abruptly returned to the initial level. The other is “a ramp increasing load”, where the fuel amount is increased gradually. Except just after the step increase in fuel amounts, the THC emissions were almost completely determined by the piston wall temperature and fuel amount. However, the THC concentrations immediately after the step increase in fuel amounts were much higher than the value of the corresponding steady state operation with the same piston wall temperature. This overshoot concentration, ΔTHC, was almost constant at different intervals, Δtint and it can be suppressed by ramp increased loading.

It is frequently useful to calculate the theoretical composition of the major components of vehicle exhaust. A software program has been written in Basic (or Quick Basic) which allows the convenient calculation of volume percents of CO, CO2, O2, H2, and H2O from fuel composition (H/C and O/C ratios), the water content (dew point) of the combustion air, and a chosen stoichiometry (air/fuel ratio). The program considers the Water Gas Shift reaction and the production of hydrogen under fuel rich conditions. The program is valid for both standard gasolines and oxygenated blends. Vehicle emissions data, collected to compare values calculated by the program with actual experimentally determined values from vehicle exhaust, show good agreement for measurements made at a series of air/fuel ratios ranging from lambda of 0.85-1.2.

To develop catalysts for natural gas vehicles the effects of precious metal, washcoat and catalysts combination on the removal of methane (CH4), non methane hydrocarbon (NMHC), CO and NOx were investigated. The precious metal formula studied were Pt/Rh, Pd/Rh, Pt/Pd/Rh (trimetal) and Pd only. Two types of washcoats with different compositions and coating structures were used. Model gas tests were carried out for eight kinds of catalysts and dual catalysts consisted of two single catalysts. Through FTP75 vehicle test, three 50,000 miles approximate aged catalytic converters with dual beds were evaluated. The experimental results showed that Pd only and trimetal catalysts had good catalytic performance over the CH4-CO-NO simulated gas composition. Dual bed catalysts had better CH4, CO and NO conversion performance and light off characteristics than single bed catalysts.

The reaction mechanism in a NOx-trap type catalyst for a partial lean burn engine is discussed using a thermodynamic calculation approach. The thermodynamic calculation and catalyst characterization suggest the following reaction mechanism; During lean operation, NO2, which was formed from NO oxidation reaction by precious metals, reacted with M-Carbonate(M: NOx Trap Material such as alkali earth elements) to form the corresponding M-Nitrate on the catalyst. When the A/F switches to rich, M-Nitrate decomposed to M-oxide and NO2. Released NO2 was purified to N2. M-oxide reacted with CO2 to form M-Carbonate. Thermodynamic calculation further suggested that NOx trap performance depended on the basicity of added NOx trap material, and evaluation results of the performance in Pt/Rh type catalyst supported this tendency. Furthermore, impacts of catalyst formulations and reaction parameters on NOx trap performance were investigated for identification of the NOx trap reaction mechanism.

This work investigated the characteristics of both total and methane hydrocarbon emissions from a spark-ignition research engine fuelled with natural gas and gasoline. The engine was operated at a range of equivalence ratios, spark timings and speeds. Measurements were also made during warm-up. The effects of exhaust gas recirculation at stoichiometric operation with special regard to oxides of nitrogen emissions were also investigated in a direct comparison between natural gas and gasoline fuelling at constant engine torque.

Engine and laboratory tests were carried out to examine the performance of NOx adsorption catalysts for gasoline lean burn engines in fresh and aged condition. The results show that fresh NOx adsorption catalysts have the potential to meet EURO III emission standards. However, to accomplish these the fuel must contain a low sulfur concentration and the engine must be tuned to optimize the efficiency of the catalyst. After engine or furnace aging upto 750°C the catalyst shows some loss of NOx adsorption efficiency. This deterioration can be offset somewhat by increasing the frequency of lean/rich switching of the engine. Temperatures higher than 750°C may cause an irreversible destruction of the NOx, storage features while the three-way activity of the catalyst remains intact or even may improve. With reference to several physicochemical investigations it is believed that the detrimental effect of catalyst aging is attributed to two different deactivation modes.

The use of hydrocarbon traps to reduce cold-start emissions is one of the numerous methods that have been suggested to meet ULEV hydrocarbon emission requirements. To aid in our understanding of hydrocarbon traps and in the design of improved hydrocarbon trap systems, in-situ mass spectrometry has been used to speciate several hydrocarbons during the first 505 seconds of an FTP from the exhaust of a 2.0 L vehicle fitted with hydrocarbon traps in the after treatment system. This technique allows second-by-second engine-out and vehicle-out hydrocarbon speciation. The in-situ mass specrometry technique has shown that hydrocarbon traps are generally effective for trapping aromatics and C4+ alkanes and alkenes, but are ineffective in trapping methane, ethane, and ethene: Further improvements in the trapping performance for C3-C5 hydrocarbons can be made by placing a water trap in front of the hydrocarbon trap.

Intermittent Dual-fluid Exhaust Burner (IDEB) has been developed to reduce emissions from methanol fueled vehicles during the warm-up period after a cold start. The IDEB does not need any special fuel injector or blower, and has been built mainly through software modification of an ECU. An FTP mode test while operating an IDEB confirmed that the catalyst temperature was rapidly increased to significantly reduce the emissions to meet a level of ULEV standards.

The FTP HC, CO, and especially NOx emissions of standard Pd Only three way catalysts have been demonstrated to be more sensitive to fuel sulfur content than Pt/Rh, Pd/Rh, and Pt/Pd/Rh catalysts. To understand the interaction between Pd Only three way catalysts and sulfur, a laboratory study was conducted to examine the relationships between washcoat composition, washcoat structure, and catalyst activity under various evaluation sulfur conditions. First, Pd promoters were examined for their ability to increase activity under both low and high sulfur test conditions. Second, an examination of catalyst structure demonstrated that control of the interaction between Pd and the stabilized ceria washcoat component is critical to achieving high catalyst activity under both low and high sulfur test conditions.

An increased of carbon monoxide and hydrocarbons emissions from gasoline engines in ambient temperatures at or below 0°C is a key issue, not only in Scandinavia or northern parts of the USA and Canada, but also in countries of Central and Eastern Europe. It is typical of Poland and neighbouring countries that for six to seven months (from October to April) air temperature fails to about 0°C at night, while in winter months this temperature often fails below -10 to even -20°C. Due to this, in these countries the cars are started in the morning when the engine and all other parts of the car are considerably cool. This paper presents a special climatic conditions in view of their effect on the actual exhaust emission from a car with SI engine and results of emission tests for such gaseous pollutants as CO, HC and NOx, achieved during tests performed on a chassis dynamometer according to ECE and FTP 75 cycles.

A survey of the corrosion protection practices in Europe is presented. The materials in use for the construction of the carbody and the chemical pretreatment processes applied are described in detail. Trends in electrocoating are also discussed briefly. The use of precoated/prephosphated steel and aluminum is continuously increasing. In addition trials are made with magnesium and plastic hang-on parts. In pretreatment, multi-metal and environmentally friendly processes free of nickel, nitrite and chrome are increasingly used. Some twelve body lines process aluminum hang-on parts and all-aluminum carbodies, respectively. Two body lines operate with a nickel and nitrite free phosphating process and chrome free post-treatment since early 1996. Future trends are presented for conclusion.

This paper discusses a portion of a larger program on filiform corrosion concentrating on test methodologies and environmental mechanisms that contribute to filiform corrosion. It is organized into four sections, the first covers background of filiform corrosion, materials used in the study, and procedures for the sample preparation and testing. Following this, there are sections on outdoor testing, accelerated testing, and environmental parameters all of which include some procedural information, results and conclusions.

A program was initiated to determine corrosion performance of coated sheet products. The program examined the performance of galvannealed, hot-dip galvanized and electroplated zinc coated steel sheet in a variety of cyclic laboratory corrosion tests. Both perforation and cosmetic corrosion susceptibility were evaluated. Materials were pretreated using immersion and spray phosphate systems and were also prepared without a phosphate pretreatment. Results of these studies will be presented in this paper.

With ever-increasing emphasis on the environment and the decrease in available landfill locations, the generation and disposal of phosphate sludge has become a challenge in many countries. This study examines key parameters of a trication zinc phosphating process and their effect on sludge generation. Using Design Of Experiment, (DOE), principles, the effects and interactions of the key parameters were identified and used to optimize the process to achieve a 30% reduction in sludge without compromising performance. Included in the results are the derived regression equations for sludge, coating weight, metal loss, p-ratio and APGE cosmetic corrosion.

The increase in instrument panel design and functional performance requirements has resulted in a variety of structural architectures that have been utilized in different passenger vehicles, vans, and light trucks. Each architecture can be designed and engineered to meet corporate and federal requirements using different levels of integration, functionality consolidation, and assembly simplification. The present paper reviews three basic IP design architectures, i.e., traditional, hybrid, and structural, and discusses the performance requirement-functionality matrix in each case. Emphasis is given at explaining the role components play in the different architectures, defining their contribution to static, dynamic and crash performance and their relation to the overall assembly process and sequence. Performance and functionality requirements are linked to basic material characteristics that guide material selection for achieving design targets.

Increasing use of aluminum in automotive components has led to lower fuel consumption and enhanced performance of automotive designs. From a manufacturing standpoint, aluminum provides the additional advantage of utilizing same processes as steel. Performance and durability of painted aluminum cars, however, is dependent on proper optimization of process conditions. As part of an extensive study of factors influencing corrosion resistance of painted aluminum, the present study deals with the influence of pretreatment and coating variables and the interaction of alloy composition with zinc phosphate and electrocoat. Interfacial analysis of corrosion products indicates the relative influence of alloying elements on stability of the metal/phosphate/electrocoat interface. As a result, guidelines and recommendations on aluminum processing in an automotive manufacturing floor have been developed.

Designers and engineers encounter many challenges in developing vehicles for the small-car market. They face constant pressure to reduce both mass and cost while still producing vehicles that meet environmental and safety requirements. At the same time, today's discriminating consumers demand the highest quality in their vehicles. To accommodate these challenges, OEMs and suppliers are working together to improve all components and systems for the high-volume small-car market. An example of this cooperative effort is a project involving an integrated structural instrument panel (IP) designed to meet the specific needs of the small-car platform. Preliminary validation of the IP project, which uses a compression-molded, glass-mat-thermoplastic (GMT) composite and incorporates steel and magnesium, indicates it will significantly reduce part count, mass, assembly time, and overall cost.