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Ceramic Hot tubes are developed as a cost effective substrates for 2 and 3 wheelers Catalytic Converter. These are used instead of ceramic honeycomb substrates for the applications where, lower conversion is enough to meet the emission norms. Ceramic hot tubes are more appropriate for 4-stroke two wheelers which are marginally failing to meet Indian emission norms for year 2000. The low thermal expansion cordierite based ceramic hot tubes offer very high thermal shock resistance, high temperature strength, very low back pressure and adequate geometrical surface area. The unique design of this product can withstand severe thermal stresses up to 1200°C. This is required for long durability against mechanical vibrations and extraordinary temperature rise expected in Indian two and three wheelers. Hence ceramic hot tubes have advantage over metallic hot tubes. Under the present work, two different configurations of ceramic hot tubes have been developed.

Available information in the literature has been reviewed to understand the effect of gasoline composition (olefins, aromatics and benzene) on the exhaust emissions from two and four wheeled vehicles. Studies show that isolating the effect of an individual compositional characteristics may be difficult. Aromatics in the exhaust could be correlated with the aromatics in the fuel. The benzene and toluene fractions in the exhaust were sometimes more than in the fuel because of dealkylation of higher alkyl aromatics. The olefins fraction in the exhaust were also observed to be more than in the fuel. The olefin fraction was noted to be directly proportional to the sum of olefins and paraffins in the fuel, and, inversely proportional to the aromatics. Exhaust emissions of benzene may be due to benzene content in the fuel or benzene formation during combustion or over the catalytic converter due to dehydroalkylation of the alkyl benzene.

An experimental study was conducted on in-use and new, Indian two-wheelers to study the effect of gasoline composition (olefins, aromatics and benzene) on exhaust mass emissions. Exhaust emissions of benzene were also measured. The study was conducted on six makes of new and in-use, two-wheelers consisting of popular 2-stroke and 4-stroke, mopeds, scooters and motorcycles. Three test fuels, a high olefin gasoline, a high aromatic gasoline and a Euro-III equivalent gasoline were used for the study. High olefin test gasoline contained 26.5% olefins, 10.3% aromatics and 0.3% benzene. High aromatic test gasoline contained 0.9% olefins, 61.9% aromatics and 1.5% benzene. Euro-III test gasoline contained 15.9% olefins, 37.4% aromatics and 0.9% benzene. Intake system deposit study was also conducted on 4-stroke motorcycles and two-stroke scooters having separate lubrication, using two fuels, i.e. high olefin gasoline and Euro-III gasoline, with and without the use of multi-function additives.

In India, two and three-wheelers constitute about 70% of the total in-use vehicle population and consume about 2/3rd of the total gasoline, rest of the gasoline being consumed primarily by the passenger cars. This paper presents the findings of an experimental study carried out on in-use gasoline vehicles, including two and three- wheelers and passenger cars. The gasoline fuels used for the study were equivalent to Euro-II, Euro-III and Euro-IV fuel quality specifications. The study analyzes the effect of improving the gasoline fuel quality on exhaust emissions from in-use vehicles.

In India, continuous efforts are being made to upgrade fuel quality and vehicle technology for meeting European emission norms. However, these efforts make a very little impact in improving the air quality due to exponential increase in the vehicle population and the poor quality of the Indian roads. The long-term strategy for meeting the requirement of huge road infrastructure and traffic management systems needs immediate attention. Studies have been conducted worldwide to study the effect of fuel quality and vehicle technology on fuel economy and emissions. However, the contribution of road quality, traffic management and driver training on reduction of vehicular emissions and improvement of fuel economy under Indian road conditions is still not established.

Engine components are exposed to various lubrication regimes such as hydrodynamic, elasto-hydrodynamic, boundary and mixed lubrication during engine operation. In each of these regimes, the factors which influence engine friction are different. Hydrodynamic friction is influenced by lubricant rheology, film thickness and sliding speed of interacting surfaces, whereas boundary and elasto-hydrodynamic friction is a function of surface properties like roughness and hardness and the type of friction modifier used in engine lubricant. So the principal factors which influence engine friction power are speed, load, surface topography of engine components, oil viscosity, oil temperature and type of friction modifiers used. Experimental studies on an off-highway diesel engine were conducted to investigate the effect of engine oil viscosity and engine operating conditions on engine friction power.

Environmental regulations are going to put severe demands on the oil industry for improving fuel quality. Awareness about increasing contribution of automotive vehicles to air pollution particularly in major Indian cities has led to the enforcement of more and more stringent vehicle emission regulations. Emission norms to be applicable from April 1, 2000 for gasoline and diesel vehicles call for major changes in the engine design and a substantial improvement in the present level of fuel quality. Various fuel characteristics significantly affect the vehicle emissions. Main properties of attention are content of lead, sulphur, benzene, aromatics, olefins and oxygenates, and fuel stability in case of gasoline; and cetane number, distillation range, oxidation stability, aromatics content, sulphur content and density in case of diesel fuel. This paper presents a review of the worldwide trends in fuel quality changes for meeting emission norms.

Transportation needs of society has been growing at a rapid rate and to a great extent dependent on crude oil derived fuels. The crude oil supply may fall short of demand has been clearly realized and future fuel scenarios are being studied. In this background, transport fuels and their effect on exhaust emission as well as greenhouse gases have become the driving force for their interactions with engine and emission control systems. In this paper, various transport fuel options to supplement/replace the existing fuel supply are discussed particularly considering the Indian Transport scenario.