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In recent studies, the health implications of ultra fine particle emissions from vehicles have been investigated in a number of international studies. The adverse health effects are not only dependent on total particulate mass but also on other attributes including size, number and surface area of the particles. These ultra fine particles cause more adverse effect than larger particles. With this need UNECE GRPE had launched a Particulate Measurement Program (PMP) to formulate the regulation to control both particulate mass and number of ultra fine particles. These new regulations are applicable to the diesel and gasoline direct injection passenger cars and heavy duty engines of Euro-V/VI technology. However, at present the other vehicle categories and alternate fuels are not been covered. Limited experiments have been carried-out on the in-use vehicles which are with old technologies.

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.

The exhaust emission legislation for automotive vehicles came into effect in India from 1991. Since then, the exhaust mass emission certification tests are conducted on a prototype vehicle for emission compliance before commencing commercial production. The exhaust emission norms are reviewed and tightened after every five years. This should lead to a better emission control system in new vehicles. But the old vehicles which are designed prior to emission control era continue to emit heavily due to their inherent design and condition. The problem of in use vehicle emissions will be on the rise with the low scrappage rate of old vehicles in India. The impact of implementing tighter norms for new vehicles on ambient air quality can be felt only after a period of about 10 years. To have an effective improvement in ambient air quality levels, it is necessary to identify the gross polluters and retune them for bringing their emissions to an acceptable level.

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.

In-cab booming noise is low frequency (20 Hz∼300 Hz) phenomenon excites the cabin structure, which occurs mainly due to excitations from the powertrain, exhaust system, road input, etc. Annoyance due to booming noise affects the In-cab sound quality, which results in passenger discomfort. A diesel passenger car observed booming noise issue when operated at stationary as well as dynamic run-up conditions. In order to increase passenger comfort, experimental root cause analysis conducted on the vehicle to investigate the dominant sources for the cavity boom. Exhaust hanger and one of the engine mount identified as major reason for the booming noise in the cabin. A detailed study was carried out on dynamic property optimization of rubber hanger and possibility to relocate the hanger to improve the vibration transmissibility. Operational measurements conducted on vehicle by attaching finalized exhaust mount to confirm the significant booming noise reduction in the cabin.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

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.

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.

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.

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.

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.

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.

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.

Moir� method is useful to measure the shape and the whole-field distributions of displacement and strain of structures. There are many kinds of moir� methods such as geometric moir� method, sampling moir� method, Fourier transform moir� method, moir� interferometry, shadow moir� method and moir� topography. Grating method analyzing directly deformation of a grating without any moir� fringe pattern is considered as an extended technique of moire method. Phase analysis of the moire fringe patterns and the grating patterns provides accurate measurements of shapes or displacement and strain distributions. Some applications of these moir� methods and grating methods to dynamic shape and strain distribution measurements of a rotating tire, sub-millimeter displacement measurements from long distance for landslide prediction, real-time shape measurements with micro-meter order accuracy, etc. are shown. Presenter Yoshiharu Morimoto, Moire Institute Inc.

Virtual testing is a method that simulates lab testing using multi-body dynamic analysis software. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The disadvantage is that accurate specimen models are sometimes hard to obtain since nonlinear components such as tires, bushings, dampers, and engine mounts are hard to model. Therefore, virtual testing accuracy varies significantly. The typical virtual rigs include tire and spindle coupled test rigs for full vehicle tests and multi-axis shaker tables for component tests. Hybrid simulation combines physical and virtual components, inputs and constraints to create a composite simulation system. Hybrid simulation enables the hard to model components to be tested in the lab.