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The upcoming Bharat Stage VI (BS VI) emission legislation has put enormous pressure on the future of small diesel engines which are widely used in the Indian market. The present work investigates the emission reduction potential of a common rail direct injection single cylinder diesel engine by adopting a holistic approach of lowering the compression ratio, boosting the intake air and down-speeding the engine. Experimental investigations were conducted across the entire operating map of a mass-production, light-duty diesel engine to examine the benefits of the proposed approach and the results are quantified for the modified Indian drive cycle (MIDC). By reducing the compression ratio from 18:1 to 14:1, the oxides of nitrogen (NOx) and soot emissions are reduced by 40% and 75% respectively. However, a significant penalty in fuel economy, unburned hydrocarbon (HC) and carbon monoxide (CO) emissions are observed with the reduced compression ratio.

The ignition quality of a fuel is described by its cetane number. Experimental methods used to determine cetane number employ Co-operative fuel research (CFR) engine and Ignition quality tester (IQT) which are expensive, have less repeatability and require skilled operation, and hence least preferred. There are many prediction models reported, which involve number of double bonds and number of carbon atoms whose determination is not direct. Using models that relate biodiesel composition to its cetane number is limited by the range of esters involved. Hence, a model to predict cetane number of biodiesels that addresses the limitations of the existing models, without ignoring the influence of factors such as degree of unsaturation and number of carbon atoms, is needed. Fourier transform infrared spectroscopy (FTIR) could be one such method.

This paper presents the experimental investigation of combustion stability and nano-particle emissions from the CNG-diesel RCCI engine. A modified automotive diesel engine is used to operate in RCCI combustion mode. An open ECU is used to control the low and high reactivity fuel injection events. The engine is tested for fixed engine speed and two different engine load conditions. The tests performed for various port-injected CNG masses and diesel injection timings, including single and double diesel injection strategy. Several consecutive engine cycles are recorded using in-cylinder combustion pressure measurement system. Statistical and return map techniques are used to investigate the combustion stability in the CNG-diesel RCCI engine. Differential mobility spectrometer is used for the measurement of particle number concentration and particle-size and number distribution. It is found that advanced diesel injection timing leading to higher cyclic combustion variations.

Stringent emission regulations on one hand and increasing demand for better fuel economy along with lower noise levels on the other hand require adoption of advanced common-rail direct-injection technologies in diesel engines. In the present work, a small 0.9-l, naturally aspirated, two-cylinder, common-rail direct-injection diesel engine is used for the analysis of combustion noise at different engine operating conditions. Experiments are conducted at different loads and engine speeds, incorporating both single and multiple (i.e. pilot and main) injections along with different injection timings. In the case of multiple injections, the influence of pilot injection quantity is also evaluated on the combustion noise while maintaining the same load. In-cylinder pressure was recorded with the resolution of 0.1 crank angle degree, and it was used for the quantitative analysis of noise assessed from the resulting cylinder pressure spectra, and sound pressure level.

In this work methanol was port injected while diesel was injected using a common rail system in a single cylinder non-road CI engine. Experiments were conducted with single (SPI) and double (DPI - pilot and main) injection of the directly injected diesel at 75% load and at a constant speed of 1500 rpm. The effects of methanol to diesel energy share (MDES) and injection scheduling on combustion stability, efficiency and emissions were evaluated. Initially, in the SPI mode, the methanol to diesel Energy Share (MDES) was varied, while the injection timing of diesel was always fixed for best brake thermal efficiency (BTE). Increase in the MDES resulted in a reduction in NOx and smoke emissions because of the high latent heat of vaporization of methanol and the oxygen available. Enhanced premixed combustion led to a raise in brake thermal efficiency (BTE). Coefficient of variation of IMEP, peak pressure and BTE were deteriorated which limited the usable MDES to 43%.

Biodiesel makes an attractive option to replace fossil diesel owing to its applicability in diesel engines without major modifications. An increase in NO emissions with biodiesel compared to diesel is a major concern for its wider use. Blending alcohols, such as methanol, with biodiesel is a potential remedy to mitigate NO formation, as suggested by experiments. However, computational investigations studying the effect of biodiesel-methanol blends on NO formation are scarce. A combined experimental and computational approach is adopted here to investigate the NO formation mechanism with neat biodiesel and biodiesel-methanol blend fueled light duty diesel engine. Firstly, a new compact kinetic model is utilized consisting of oxidation reactions for methyl butanoate and n-dodecane as a surrogate for biodiesel. A surrogate is defined to represent biodiesel based on a combined property and functional group based approach.

The present study discusses the effects of engine combustion, performance and emission features of methanol-gasoline blend fired lean burn Spark Ignition (SI) engine. Performance features such as Brake Power (BP), Brake Specific Fuel Consumption (BSFC), Brake Thermal Efficiency (BTE), tail pipe emissions namely Hydrocarbon (HC), Carbon Monoxide (CO), Nitrogen Oxide (NO), Carbon di Oxide (CO2) and combustion characteristics viz. in-cylinder pressure, Heat Release Rate (HRR), Cumulative Heat Release (CHR) and variation of mean effective pressure were measured and compared with that of neat gasoline. Experiments were conducted on a modified sole cylinder four-stroke compression engine (Kirloskar TAF1) to operate as SI engine with a compression ratio of 10.5:1. A new manifold injection system and ignition system were developed by replacing the fuel injection pump and injector.

Autonomous driving is looked upon as solution for future of automotive vehicles. The technology has tremendous possibilities to improve safety, fuel economy, comfort, cost of ownership etc. The project to develop an autonomous controller from scratch was undertaken, with objective to drive under selected test scenarios. The car, modified to drive using this autonomous controller, is able to handle these scenarios. The key scenarios include ability to successfully drive on tracks with well-marked lanes, Follow the route as per selected trip plan file, recognize and follow all traffic road signs, traffic signals en-route, identify other vehicles on the road or pedestrians in the lane and take the appropriate action. The development was carried out using frugal engineering approach. As the Autonomous Vehicle technology is still under development, the standard proven published approaches are not available.

Small single & two cylinder diesel engines, still have primitive technical design features and extensively used in India and various Asian countries to power small and light motor vehicles viz., three wheelers, light duty four wheelers. These vehicles have become inevitable for the transport for both urban and rural areas. Vehicles with small single & two cylinder engines have high market demand in commercial transport due to restrictions on entry of Heavy Commercial Vehicles (HCV) in congested cities roads. Due to ever rising market demand for higher power and torque requirement along with better fuel economy, vehicle manufacturer are developing high Brake Mean Effective Pressure (BMEP) engines or replacing single cylinder engine by two cylinder engine, similarly two cylinder engine by three cylinder engines. Further, these engines should meet the present and forthcoming stringent emission limits.

Severe air pollution in cities caused largely by vehicular emissions, which requires urgent remedial measures. As automobiles are indispensable modes of personal and public mobility, pre-emptive efforts are necessary to reduce the adverse effects arising from their operation. A significant improvement in air quality can be achieved through large-scale introduction of vehicles with extremely low emission such as hybrid-electric and zero emission vehicles. Range extension of electric vehicles (EVs) is also of utmost importance to alleviate the handicap of restricted mileage of purely plug-in EVs as compared to conventional vehicles. This paper presents development of a polymer electrolyte membrane (PEM) fuel cell stack used for the range extender electric vehicles. The Fuel cell stack for range extender vehicle operated in a dead end mode using hydrogen and air as open cathode.

With increased vehicular traffic density a trend has been observed where customers have started preferring automatic transmission in place of its manual version. This Automatic transmission not only shifts the gear automatically, with the help of sensors and actuators, but they are also tuned for better performance of the vehicle in terms of fuel efficiency and emission. This all comes at the cost of power consumption from the battery, increment in cost, weight and complexity. The main parts of an automatic transmission include Torque Convertor, Sensors, Actuators, Transmission Control Unit (TCU) with the epicyclic gear-train being the heart of it. In terms of use in the automotive, a system of epicyclic gear-train can provide only 2 gear ratios. Ravigneaux gear-train is the modified version of epicyclic gear-train where there are two set of Planet gears and Sun gears or Ring gears thereby capable of giving 4 gear ratios with a single system.

The objective of this study is to develop, demonstrate and validate the methodology of external aerodynamic analysis of a State Road Transport bus for prediction of drag coefficient and its impact on fuel consumption with experimental validation. It has been verified that vehicle consumes around 40% of the available engine power to overcome the air drag. This gives us a huge scope to study the effect of aerodynamic drag. Baseline model of State Road Transport Bus was evaluated for estimating fuel consumption using Computational Fluid dynamics (CFD) methodology. The CFD results were validated with the experimental data with less than 10% deviation. Bus design was optimized with an objective of reducing the fuel consumption with parameters like angle of windshield, rounding and tapering corners and rear draft angle. Optimized bus design is also ensured to meet functional specifications as per AIS052.

Light weighting is significant in for automotive industry as it helps in less fuel consumption and to achieve better performance. Aluminium is a candidate material for light weighting. To design a component made of aluminium material, it is necessary to understand the fatigue performance of the material. In this paper, a study is carried out to understand the fatigue performance of aluminium 6xxx series alloys at an early stage of design without carrying out comprehensive fatigue testing. Coffin Manson Parameters are used to predict fatigue life. This research focusses on determining the gaps in existing models for aluminium alloys by carrying out comprehensive review of various models developed for 6xxx series which uses monotonic tensile data. Two models are developed and the predicted fatigue properties for this class of material are further compared with experimental fatigue, monotonic data and literature.

Air pollution in India and also global warming are two major concern in the country. To address this situation, India is moving from BS-IV to BS-VI for on-road applications with 90% reduction in NOx and 50% in PM with limit on particulate number. Also moving to Trem-IV and Trem-V for off-road applications subsequently. It needs higher efficiency after-treatment systems like SCR and DPF to achieve such lower emission levels. Addition of these complex after-treatment system, severely increase the cost of diesel power plant with heavy penalty on fuel economy. Hence, it is challenge to auto industry to reduce the complexity and cost, so that it requires an alternate solution to reduce NOx and PM emissions at source to reduce cost and system complexity. Low Temperature Combustion (LTC) is a potential concept to reduce the NOx and PM emissions simultaneously.

The use of polymers in automobiles is increasing constantly and this trend is expected to continue. This clearly indicates that polymer are choice of materials in all the application sectors including in Automobile sector. The main properties in selecting the plastics materials as compared to other materials applied in automobiles are the aesthetic of automotive vehicles, their functionality and cost effective solution, as well as fuel efficiency. These materials are offer remarkable range of appealing properties, the effect of climatic conditions on the degradation and performance of these materials is not fully understood. It is necessary to know the variation of the mechanical properties of any polymer component in automobile after exposed to different atmospheric conditions before particular application. Generally when these components are subjected to weathering effects, they are prone to underperform.

Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. DI diesel engines with four valves per cylinder are widely used in off- highway applications because of the fundamental advantages of higher volumetric efficiency, lower pumping loss, symmetric fuel spray & distribution in combination with the symmetric air motion which can give nearly optimal mixture formation and combustion process. As a result, the fuel consumption, smoke levels and exhaust emissions can be considerably reduced. In particular, the four-valve technology, coupled with mechanical low pressure and electronic high pressure fuel delivery systems set different requirements for inlet port performance. In the present paper four valve intake port design strategies are analysed for off highway engine using mechanical fuel injection systems.

Because of higher NOx and PM emissions Compression Ignition (CI) engines are slowly being replaced by gas engines in metro cities though CI engine have better thermal efficiency and emit less Carbon monoxide (CO) and Unburned Hydrocarbons (UHC) emission than SI engines. Pollutants formed during combustion, depleting fossil fuels and continuous raising fuel price pushes the research community to find new alternative fuels which can be used along with diesel or replace the diesel without making major modifications in the current engine. The objective of this research work is to derive bio-diesel fuel from the source of algae and use it as a fuel by blending with commercially available diesel fuel. Heptanol is added along with algae bio-diesel and diesel blend to improve the ignition quality of the blend. Tests were conducted on a single cylinder constant speed, water cooled stationary diesel engine with different blends proportions of heptanol-biodiesel-diesel.

Diesel engines dominate in Heavy-Duty applications due to its better fuel economy, higher durability and larger reliability. Fuels derived from petroleum resources are depleting daily and it’s become a scarce resource for future generation to come. With growing environmental consciousness of the adverse implications brought by excessive usage of fossil fuels, the battle for finding alternative fuels as their substitution is getting heated up. At present, renewable energy from bio-fuels has been peddled as one of the most promising substitution for petroleum derived diesel. Using bio-ethanol blended diesel fuel for automobile can significantly reduce diesel usage and exhaust greenhouse gases. Bio-ethanol can be produced by alcoholic fermentation of sucrose or simple sugars. The main drawback is that ethanol is immiscible with diesel fuel over a wide range of temperatures, and the hygroscopic nature of ethanol leading to phase separation in blend.

It is an established fact that virtual knowledge based engineering has revolutionized R & D activities by streamlining processes, ensuring productivity and accuracy. This has resulted in freeing up time for quality interpretational work and decision making for engineering the best of products. Subsequently, homologation is a mandatory requisite activity for product signoff. It certifies the quality of the product and is an important factor in giving the product an authenticity for sale in the market. Homologation entails compliance to regulations existing in form of well-established standards which elaborate systematic and detailed guidelines on conducting physical testing for automotive systems, sub-systems or components for specific vehicle types.

Gasoline direct injection (GDI) engines have gained popularity in the recent times because of lower fuel consumption and exhaust emissions compared to that of the conventional port fuel injection (PFI) engine. But, in these engines, the mixture formation plays an important role which affects combustion, performance and emission characteristics of the engine. The mixture formation, in turn, depends on many factors of which fuel injector location and orientation are most important parameters. Therefore, in this study, an attempt has been made to understand the effect of fuel injector location and nozzle-hole orientation on the mixture formation, performance and emission characteristics of a GDI engine. The mixture stratification inside the combustion chamber is characterized by a parameter called “stratification index” which is based on average equivalence ratio at different zones in the combustion chamber.