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Hydrocarbon based fossil fuels are being used as the main energy resource, burning of which produces carbon dioxide (CO2) and other emissions harmful to environment. Moreover, CO2 is considered as the main contributor to global warming or greenhouse effect. These are the main drivers behind the ongoing research & development in the area of alternative energy sources. Among various alternatives, Hydrogen is identified as the most promising alternative fuel. Hydrogen is the cleanest fuel having some of the most attractive features such as various methods of production from renewable energy (solar, wind, biomass etc.), from fossil fuels etc. H2 as a fuel can be used in various applications such as spark ignition engine, fuel cells etc. Hydrogen has low ignition energy and ensures easy ignition of the ultra-lean mixture with air.

Improvement in fuel economy and reduction in emissions are the two major driving forces in the advancement of automotive engine technologies, fuel quality, lubricants, and aftertreatment devices. Engine design, operating conditions such as speed and load, and engine oil behavior have a significant influence on engine friction and then the vehicle fuel economy. There is no standard short duration engine test available to evaluate engine oil’s friction. This study developed a test protocol to discriminate friction reduction efficacy of engine oils/additives to support in the development of engine oils. The engine test facility was modified to conduct the motoring test over the speed range of 1000 - 4500 rpm and at 50 - 100 °C coolant and oil temperatures. Different viscosity grades and additive chemistry i.e. combination of friction modifiers & viscosity modifiers was evaluated over the motored torque test.

Ambient temperature conditions, engine design, fuel, lubricant and fuel injection strategies influence the cold start performance of gasoline engines. Despite the cold start period is only a very small portion in the legislative emission driving cycle, but it accounts for a major portion of the overall driving cycle emissions. The start ability tests were carried out in the weather controlled transient dynamometer - engine test cell at different ambient conditions for investigating the cold start behavior of a modern generation multi-point fuel injection system spark ignition engine. The combustion data were analyzed for the first 200 cycles and the engine performance and emissions were analyzed for 300 s from key-on. It is observed that cumulative fuel consumption of the engine during the first 60 s of engine cold starting at 10 °C was 60% higher than at 25 °C and resulted in 8% increase in the value of peak speed of the engine.

The growing transportation sector worldwide has opened up a way forward not only for the scientists & researchers but also for the OEMs to find out the options for fuel efficient automotive vehicles with reduced emissions during their usage. The demand of automotive vehicles has been doubled in last few years and in turn the market for lubricants and transmission fluids are flourishing. Several new formulations of lubricants are getting popularized with major suppliers to achieve the end user expectations in terms of fuel economy benefits, engine life and emissions. The market trend is continuously moving towards the improvement in lubricant formulation to the lower viscosity ranges and in this direction several companies are into development of multi-grade low viscosity range of engine oils (lubricants) which is said to be providing the benefits in terms of fuel economy.

In the light of major research work carried out on the detrimental health impacts of ultrafine particles (<50 nm), Euro VI emission standards incorporate a limit on particle number, of which ultrafine particles is the dominant contributor. As Compressed Natural Gas (CNG) is a cheaper and cleaner fuel when compared to diesel, there has been a steady increase in the number of CNG vehicles on road especially in the heavy duty segment. Off late, there has been much focus on the nature of particle emissions emanating from CNG engines as these particles mainly fall under the ultrafine particle size range. The combustion of lubricant is considered to be the dominant source of particle emissions from CNG engines. Particle emission due to lubricant is affected by the oil transport mechanisms into the combustion chamber which in turn vary with engine operating conditions as well as with the physico chemical properties of the lubricant.

To tackle the problems associated with the volatility of crude oil prices and ever stringent emission norms, oil industries and automobiles manufacturers are experimenting with various alternative fuels to increase its percentage share in the energy mix and to reduce the vehicular emissions. Alcohols are preferred choice of alternative fuels for the gasoline engines as it does not require any major engine modification and new infrastructure for the fuel distribution network. Ethanol as sole fuel or blending component for gasoline for use in spark ignition engines has been investigated many decades. Currently, 10% ethanol is blended in motor gasoline in India and the ethanol concentration may be further increased in future. In order to study the effect of higher blends of ethanol (upto 20%) on engine in-cylinder combustion, performance and emission, investigations were carried out on a latest generation passenger car engine in a climatic controlled test cell.

Alcohols are preferred choice of alternative fuel for gasoline engines to tackle the problems associated with nation’s energy security and environmental pollution. Ethanol can be used as a sole fuel or gasoline blending component for use in spark ignition engines. BIS Specification 2796: 2013 permitted to blend 10% ethanol in gasoline and the concentration may be further increased in coming years in India. Research on combustion of ethanol blended gasoline on modern gasoline engine is highly desirable. This paper highlights the experimental investigation carried out on the latest generation multipoint fuel injection system passenger car engine fueled with ethanol-gasoline blends in a climatic controlled test cell to study the in-cylinder combustion, performance and emission characteristics. Part load tests at regular speed intervals were conducted using ethanol blends. Combustion duration decreased with increase in engine load and speed for the all test fuels.

In this paper, the characteristics of particle size distribution in the exhaust of a turbocharged 5.9 liter Cummins gas engine lubricated by two commonly used oils of different viscometrics (15W-40 and 20W-50) have been investigated. The study also attempts to differentiate the performance of the lubricants on the basis of fuel economy. A test procedure developed in- house was used for the evaluation, wherein the engine was operated at various speeds (1200-2800rpm) and load (25 %, 50% & 75%) conditions. Particle size distribution is measured using Engine Exhaust Particle Sizing Spectrometer (TSI EEPS Model 3090). Results indicate that a majority of the particle emissions are observed in the nucleation region (particle diameter < 50nm) and particle size distribution is found to significantly vary with engine speed.

Volatile Organic Compounds (VOCs) present in ambient air are potentially toxic among the air pollutants. They are present in the urban atmosphere due to both exhaust emissions from vehicles and evaporative emissions at fuel filling stations. The present study aims to provide an indication of ambient levels of benzene, a carcinogenic VOC in the immediate vicinity of petrol filling stations in Delhi & National Capital Region (NCR). The monitoring of benzene is conducted across the vicinity of petrol stations to ascertain the effect of outside pollutant concentration on forecourt area. Continuous monitoring of benzene was achieved by an air quality monitoring facility stationed across the selected locations at four selected fuel filling stations. It was observed that the average concentrations of benzene measured during the study ranged between 2.28 ppb - 9.43 ppb.

In this paper, experimental evaluation was carried out on a 6.0 L heavy duty CNG engine which has been optimized for 18 percent hydrogen blended CNG (HCNG). Optimization test results shows that use of HCNG results in reduced CO, THC & CH4 emissions by 39, 25 & 25 percent respectively and increase in NOx by 32 percent vis-a-vis CNG. After optimization the engine was subjected to endurance test of 600 hours as per 15 mode engine simulated city driving cycle with HCNG. The performance & emission characteristics of the engine were analyzed after completion of every 100 hours as per European Transient Cycle (ETC). Test results indicate that there were no significant changes observed in engine power output over the complete endurance test of 600 hrs with HCNG. Specific fuel consumption (SFC) measurements were consistent at all the 15 modes of engine simulated city driving cycle.