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“Trapless” Trap, which makes possible the effective collecting of particulates in diesel exhaust gas and their simultaneous combustion has been developed by use of a ceramic foam in combination with catalysts containing copper salt. From a TEM photograph, it was observed that the particulate was rapidly oxidized by mobile copper ion, showing worm-eaten like spots. Screening of various base metal salts by TGA presented CUCl2-KCl-NH4VO3 and CuCl2-KCl-(NH4)6Mo7O24 as very active catalysts for diesel particulate oxidation. They had thermal stability up to 900°C when they were supported on titania. The results obtained by measuring the back pressure using 1.8L diesel engine suggest the above trap to be a self-cleaning trapless trap.

This study mainly focuses on the blending of Alumina and Titanium oxide nanoparticles (NP’s) in Spirulina biodiesel blends (SB20) to estimate the influence of engine (combustion, performance and emission) parameters of a diesel engine. The characterization of Al2O3 and TiO2 NP’s like SEM were reported. By using various fuel samples such as Diesel, SB20, SB20+40 ppm AO, SB20+80 ppm AO, SB20+40 ppm TO and SB20+80 ppm TO, the engine tests on the diesel engine were conducted at various load conditions. The BTE for SB20+80 ppm AO were enhanced by 12.35% and 8.4 % compared to the SB20 fuel and SB20+40 ppm AO fuel samples. The combustion parameters were improved for the NP’s as additives (Al2O3 and TiO2) fuels than the SB20 fuel sample because NP’s contain oxygen content. The parameters of engine exhaust emissions such as HC, CO and smoke are drastically diminished for the SB20+40 ppm AO, SB20+80 ppm AO, SB20+40 ppm TO and SB20+80 ppm TO fuels compared to the SB20 fuel.

Advanced diesel engines developed for the commercial market need to be adapted to the military requirements by OPERAS (Optimizing the injection pressure P, the Exhaust gas recirculation E, injection events Retard and/or Advance and the swirl ratio S). The different after treatment devices, already used or expected to be applied to diesel engines, require feed gases of appropriate properties for their efficient operation. To produce these gases some OPERAS are needed to control the diesel combustion process. Since military vehicles do not need the after treatment devices, the OPERAS of the commercial engines should be modified to meet the military requirements for high power density, better fuel economy, reduction of parasitic losses caused by the cooled EGR system, and reduction of invisible black and white smoke in the field.

An two-dimensional axial symmetrical finite volume model will be introduced for the calculation of catalytic converters. It is able to predict transient temperatures and conversion rates in different converter systems according to the driving conditions. Input data are the mass-flow rate, the converter inlet temperature and the raw emissions. The performance of this model is demonstrated on an Indian motorcycle application. Cold start behavior and peak temperatures are investigated. This model has proven to be an effective tool for the preselection of an optimal cost effective catalyst system.

Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries are required to reduce vehicle emissions and to participate in a cleaner and healthier environment. As a contribution Continental Emitec started a comprehensive testing program with a state of the art 180 cc Bharat Stage (BS) III Indian motorcycle. The program consists of testing the state of the art of Metallic substrates with structured foils with various catalyst sizes and positions (original or close coupled). The publication presents a short literature survey and the results of the investigation with a big catalyst volume mounted in underfloor position as well as in close coupled position, gained over the World-wide harmonized Motorcycle Test Cycle, considering the two possible vehicle classifications of this motorcycle, Sub-Class 2.1 and Sub-Class 2.2.

Due to the rising costs of fuel and increasingly stringent regulations, auto makers are in need of technology to enable more fuel-efficient powertrain technologies to be introduced to the marketplace. Such powertrains must not sacrifice performance, safety or driver comfort. Today's engine and powertrain manufacturers must, therefore, do more with less by achieving acceptable vehicle performance while reducing fuel consumption. One effective method to achieve this is the extreme downsizing of current direct injection spark ignited (DISI) engines through the use of high levels of boosting and cooled exhaust gas recirculation (EGR). Key challenges to highly downsized gasoline engines are retarded combustion to prevent engine knocking and the necessity to operate at air/fuel ratios that are significantly richer than the stoichiometric ratio.

Ammonia is one of the most useful compounds that react with NOx selectively on a catalyst, such as V2O5-TiO2, under oxygen containing exhaust gas. However ammonia cannot be stored because of its toxicity for the small power generator in populated areas or for the diesel vehicles. A new concept for NOx reduction in diesel engine using ammonia is introduced. This system is constructed from the hydrogen generator by fuel reformer, the ammonia synthesizer, SCR catalyst for NOx reduction and the gas injection system of reformed gas into the cylinder. Experimental results show that, the SCR catalyst provides a very high rate of NOx reduction, reformed gas injection into cylinder is very effective for particulate reduction. WHEN CONSIDERING INTERNAL COMBUSTION ENGINES of the 1990's the question of how to harmonize the engine with the natural environments is one of the greatest problems. The internal combustion engine changes a substance into energy via its explosive combustion.

Abstract An investigation into the pre-ashing of new gasoline particulate filters (GPFs) has demonstrated that the filtration efficiency of such filters can be improved by up to 30% (absolute efficiency improvement) when preconditioned using ash derived from a fuel-borne catalyst (FBC) additive. The additive is typically used in diesel applications to enable diesel particulate filter (DPF) regeneration and can be added directly into the fuel tank of the vehicle. This novel result was compared with ash derived from lube oil componentry, which has previously been shown to improve filtration efficiency in GPFs. The lube oil-derived ash utilized in this work improved the filtration efficiency of the GPF by −30%, comparable to the ash derived from the FBC additive.

Φ-sensitivity is a fuel characteristic that has important benefits for the operation and control of low-temperature gasoline combustion (LTGC) engines. A fuel is φ-sensitive if its autoignition reactivity varies with the fuel/air equivalence ratio (φ). Thus, multiple-injection strategies can be used to create a φ-distribution that leads to several benefits. First, the φ-distribution causes a sequential autoignition that reduces the maximum heat release rate. This allows higher loads without knock and/or advanced combustion timing for higher efficiencies. Second, combustion phasing can be controlled by adjusting the fuel-injection strategy. Finally, experiments show that intermediate-temperature heat release (ITHR) increases with φ-sensitivity, increasing the allowable combustion retard and improving stability. A detailed mechanism was applied using CHEMKIN to understand the chemistry responsible for φ-sensitivity.

This paper presents a numerical study on the impact of washcoat diffusion on the overall conversion performance of catalytic converters. A comprehensive transient 1D pore diffusion reaction model is embedded in state-of-the-art 1D and 3D catalytic converter models. The pore diffusion model is discussed with its model equations and the applied diffusive transport approaches are summarized. The diffusion reaction model is validated with the help of two available analytical solutions. The impact of basic washcoat characteristics such as pore diameters or thickness on overall conversion performance is investigated by selected 1D+1D calculations. This model is also used to highlight the impact of boundary layer transfer, pore diffusion and reaction on the overall converter conversion performance. The interaction of pore diffusion and flow non-uniformities is demonstrated by 3D+1D CFD simulations.

HEAT TRANSFER causes loading and starting design problems in large missile systems powered by cryogenic propellants. This manifests itself during loading as effective density variation, violent surface conditions, boiloff, and ice formation — problems which may be solved by insulating the tank. During starting it causes overheating and caviation — effects which may be reduced by recirculators and subcooled charge injections. The study described in this paper centers around liquid oxygen and its variations in heat flux rate, which affect liquid density, surface condition, and replenishing requirements. The problem areas are made apparent by consideration of a hypothetical missile system.*

Reduced emissions, improved fuel economy, and improved performance are a priority for manufacturers of internal combustion engines. However, these three goals are normally interrelated and difficult to optimize simultaneously. Studying the experimental heat release provides a useful tool for combustion optimization. Heavy-duty diesel engines are inherently transient, even during steady state operation engine controls can vary due to exhaust gas recirculation (EGR) or aftertreatment requirements. This paper examines the heat release and the derived combustion characteristics during steady state and transient operation for a 1992 DDC series 60 engine and a 2004 Cummins ISM 370 engine. In-cylinder pressure was collected during repeat steady state SET and the heavy-duty transient FTP test cycles.

“Zoning” a catalytic converter involves placing higher concentrations of platinum group metals (PGM) in the inlet portion of the substrate. This is done to optimize the cost-to-performance tradeoff by increasing the reaction rate at lower temperatures while minimizing PGM usage. A potentially useful application of catalyst zoning is to improve performance using a constant PGM mass. A study was performed to assess what the optimum ratio of front to rear palladium zone length is to achieve the highest performance in vehicle emission testing. Varying the zone ratio from 1:1 to 1:9 shows a clear hydrocarbon performance optimum at a 1:5.66 (15%/85%) split. This performance optimum shows as both a minimum in FTP75 non-methane organic gas (NMOG) emissions as well as a minimum in hydrocarbon, carbon monoxide, and nitrogen oxide light-off temperature. Overall, an improvement of 18%, or 11 mg/mi of combined NMOG+NOx emissions was obtained without using additional PGM.

This paper will review the role of zirconium oxide in automotive systems. Zirconium oxide has been used and been considered for use in many different applications within automotive systems. Examples include ceramics for engine liners, ionic conductors for oxygen sensors, piezoelectrics for a variety of sensors and as an ingredient of autocatalysts. In the first three examples, ceramics, ionic conductors and piezoelectrics, the known properties of zirconium oxide containing systems have been applied to solve problems in the automobile. In the last the use of zirconia here has created an interest outside automotive applications. This paper will also show how a knowledge of zirconia in one field can produce benefits in another and that through this synergy improved products can be brought to the marketplace

A zirconia electroysis cell is an all-solid state (mainly ceramic) device consisting of two electrodes separated by a dense zirconia electrolyte. The cell electrochemically reduces carbon dioxide to oxygen and carbon monoxide at elevated temperatures (800 to 1000°C). The zirconia electrolysis cell provides a simple, lightweight, low-volume system for Mars In-Situ Resource Utilization (ISRU) applications. This paper describes the fabrication process and discusses the electrochemical performance and other properties of zirconia electrolysis cells made by the tape calendering method. Electrolytes produced by this method are very thin (micrometer-thick); the thin electrolyte reduces ohmic losses in the cell, permitting efficient operation at temperatures of 800°C or below.

Zero-dimensional heat release rate models have the advantage of being both easy to handle and computationally efficient. In addition, they are capable of predicting the effects of important engine parameters on the combustion process. In this study, a zero-dimensional combustion model based on physical and chemical sub-models for local processes like injection, spray formation, ignition and combustion is presented. In terms of injection simulation, the presented model accounts for a phenomenological nozzle flow model considering the nozzle passage inlet configuration and an approach for modeling the characteristics of the Diesel spray and consequently the mixing process. A formulation for modeling the effects of intake swirl flow pattern, squish flow and injection characteristics on the in-cylinder turbulent kinetic energy is presented and compared with the CFD simulation results.

This study aims at a new concept for a fast catalyst light-off in combining a latent heat storage with a catalyst. The arrangement of a latent heat storage device into the exhaust system offers significant benefits for the catalyst light-off. Different arrangements have been examined. The first arrangement, called the sequential arrangement, comprises a latent heat storage device and a subsequent catalyst. This offers a significantly faster heat up of the catalyst compared to the standard arrangement. By that emissions during the cold start phase can be significantly reduced. The setup of the latent heat storage device is designed for a high heat transfer between storage material and the exhaust gas. A second integrated arrangement of a latent heat storage and a catalyst into one common substrate has also been set up and investigated. The main advantage of this arrangement is that the catalyst itself is kept on its operation temperature during the engine off time.

A precise estimation of the recirculated exhaust gas rate and oxygen concentration as well as a predictive evaluation of the possible EGR unbalance among cylinders are of paramount importance, especially if non-conventional combustion modes, which require high EGR flow-rates, are implemented. In the present paper, starting from the equation related to convergent nozzles, the EGR mass flow-rate is modeled considering the pressure and the temperature upstream of the EGR control valve, as well as the pressure downstream of it. The restricted flow-area at the valve-seat passage and the discharge coefficient are carefully assessed as functions of the valve lift. Other models were fitted using parameters describing the engine working conditions as inputs, following a semi-physical and a purely statistical approach. The resulting models are then applied to estimate EGR rates to both conventional and non-conventional combustion conditions.

The sparking behavior in an internal combustion engine affects the fuel efficiency, engine-out emissions, and general drivability of a vehicle. As emissions regulations become progressively stringent, combustion strategies, including exhaust gas recirculation (EGR), lean-burn, and turbocharging are receiving increasing attention as models of higher efficiency advanced combustion engines with reduced emissions levels. Because these new strategies affect the working environment of the spark plug, ongoing research strives to understand the influence of external factors on the spark ignition process. Due to the short time and length scales involved and the harsh environment, experimental quantification of the deposited energy from the sparking event is difficult to obtain. In this paper, we present the results of x-ray radiography measurements of spark ignition plasma generated by a conventional spark plug.

This paper reviews the trend in worldwide exhaust emission regulations for heavy-duty diesel engines and common key technologies that must be developed and applied in order to meet these regulations. The common key technologies are intake and exhaust system with turbocharger and intercooler, electronically controlled high-pressure fuel injection system, exhaust gas recirculation, and exhaust gas after-treatment devices. This paper also introduces test results of common key technologies, concepts for low-emission heavy-duty diesel engines, and the possibilities for meeting future exhaust emission legislation is described.