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The research on reducing emissions from automotive engines through modifications in the combustion mode and the fuel type is gaining momentum because of the increasing contribution to global warming by the transportation sector. The combustion and emission formation in the advanced low temperature combustion (LTC) engine strategies are susceptible to fuel molecular composition and properties. Ignition timing in LTC strategies is primarily controlled by fuel composition and associated chemical kinetics. Thus, tailoring of fuel properties is required to address the limitations of LTC in terms of lack of control on ignition timing and narrow engine operating load range. Utilizing fuel blends and additives such as nanoparticles is a promising approach to achieving targeted fuel property. An improved understanding of fundamental processes, including fuel evaporation, is required due to its role in fuel-air mixing and emission formation in LTC.

The demand for compression ignition engines is continuously growing due to their good fuel efficiency. But they cause lot of concern with regard to exhaust emissions. This concern sought to examine ways by which the composition of the fuel used by CI engines could be changed to reduce emissions. The addition of oxygen containing compounds to diesel fuel has been proposed as a method to complete the oxidation of carbonaceous particulate matter and associated hydrocarbons. In addition many oxygenate have high cetane number and their association with diesel results in high cetane number and hence lower exhaust emissions. Due to this advantages, there is growing interest in the introduction of oxygenates into diesel fuel. The performance and emission characteristics of two kinds of oxygenates 2-Ethoxy Ethyl Acetate, 2-Butoxy Ethanol with three different blends were investigated.

The determination of power train is one of the fundamental steps in any new vehicle development process. This process is generally iterative in manner and accurate prediction of performance and fuel consumption is required to achieve the different vehicle performance targets. The use of AVL cruise simulation techniques to improve the vehicle development process has been rapidly expanding over the last decade. This simulation technique allows us to speed up the optimization of vehicle and power train parameters (vehicle weights, frontal area, Cd, engine power, engine torque and gear ratios etc.,) in an early stage of the development process. This paper establishes the simulation model of a production vehicle through different stages of vehicle development process.

Faster development cycles and longer design lifetimes, are the dominant factors for developing new testing methodologies. Especially durability testing being one of the main fields of interest has to deal with both these aspects. Physical verification of longer design lifetimes yields to longer testing time, whereas a shorter period is required to reduce the development time. The methodology described in this paper addresses these aspects to ensure a fast, customer-correlated driveline testing without loosing the fatigue relevant impact. The fatigue relevant loading of a gear tooth of a rotating gear wheel depends on the applied torque and angular speed. At present, Powertrain aggregates are tested on a rig with block loading cycle derived from designed peak torque. However, these tests neglect the dynamic behavior of the Powertrain system, as the test program does not cover high amplitude cycles from torque reversals. This may lead to underestimated results.

The global economy strives towards clean energy in the phase of climate change and the automotive industry is researching in improving the efficiency of automobiles. In respect to that, direct injection types of diesel engines are becoming popular. However, improving the performance and reducing the CO₂ emission of a vehicle is necessary in order to meet the fuel economy targets. A turbocharged common rail direct injection diesel engine is selected for investigation purpose to study its performance and average fuel consumption values over typical driving cycles (UDC, EUDC and BS IV). Experimental work is carried out to collect the vehicle performance and fuel economy test data. The simulation tools are used to speed up the product development process and to bring the new products into the market. The AVL Cruise simulation technique allows us to speed up the optimization of vehicle and powertrain parameters in an early stage of the product development process.

Micro and Mild Hybrid Systems is a bracket term, which covers functions like Engine Stop/Start (ESS), Intelligent Alternator Control (IAC), and many others, which collectively aim at optimizing the fuel consumption by preventing the wasteful running of the engine. Engine Stop/Start system is the prominent part of the Micro/Mild hybrid systems and is the most significant contributor while reducing the fuel consumption and greenhouse gas emissions. In the previous work of the Authors, various issues related to ESS were discussed in detail. ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the customer behavior. In addition, due to various functional safety conditions, and the traffic conditions, the actual benefits of ESS are negatively impacted. Therefore, it becomes necessary to have a different approach to the design of the systems like ESS.

In this paper, a methodology is discussed to achieve cost-effective solutions for improving vehicle Noise, Vibration and Harshness (NVH) performance of a body-on-frame Multi-Utility Vehicle (MUV). The subject vehicle had objectionable levels of in-cab boom and gear rattle while accelerating in higher gears due to power-train and driveline excitations. Potential transfer paths which might be responsible for amplifying these phenomena were tracked using contemporary noise and vibration measurement techniques. Various modifications were evaluated to improve NVH performance under constraints of vehicle-packaging. An optimized combination of these modifications resulted in improvements in the NVH performance over a wide range of operating speeds with reductions of up to 10 dB achieved in firing frequency excitation, thus eliminating the objectionable boom and gear rattle from the vehicle.

Refinement of vehicle interior and exterior noise is becoming more important for occupant comfort and perception of product quality. Recent trends show that modern cars have refined powertrains and as a result other parameters like road and wind noise start dominating. The objective of current work is to establish a structured methodology for analysis of road noise using fairly established techniques like sound quality analysis, operational deflection shape analysis, modal analysis and transfer path analysis. The approach includes road noise characterization, identification of frequencies responsible for road noise, estimation and ranking of contribution of individual frequency noise and vibration through different structural transmission paths from wheel - suspension to the vehicle body. This work also critically examines body modal response, body attach point sensitivities and suspension characteristics.

Automotive industry is focusing on NVH reduction and customer comfort for passenger vehicle. Structural optimization is a one of the effective tool to obtain an optimum design to achieve NVH reduction. For an internal combustion engine, there exist two basic dynamic disturbances: a) the firing pulse due to the explosion of the fuel in the cylinder and b) the inertia force and torque caused by the rotating and reciprocating parts (piston, connecting rod and crank). The usage of engine mounts is the best solution for dampening the effect of vibrations and transmitting forces between the engine and the automotive body structure. In this paper, application of structural optimization in the design of a engine mount has been carried out. Effort has been taken to develop engine-mounting arm with two different designs solution. Further, engine with two different configurations has been tested at Engine test bed and vehicle level to understand the behaviour in real environment.

In India, , as per mandate of hon'ble Supreme Court of India for reduction of emission due to vehicles, compressed natural gas (CNG) powered city buses and passengers cars are in use since 2000. Their usage is limited to metropolitan cities like Delhi, Mumbai, Bangalore etc. due to limitation of CNG storage and dispensing infrastructure along with low energy density storage. High energy density liquid form of natural gas storage (LNG) can overcome these difficulties and promising in near future. Simultaneously, there is a need for development of efficient fuel storage system, fuel supply system, engine optimization & calibration, engine lubricant etc. suitable for implementation of LNG for automotive application. In this background, the present work is aimed at the framework of engine testing facility, development of dedicated lubricant and performance of the engine for LNG application.

ISO 26262 is an Automotive functional safety standard for Electrical and Electronic system. This paper details application of this standard for hybrid powertrain. The concept of functional safety has been analyzed. First item definition for hybrid powertrain is detailed out. Item definition includes system description, its function, boundary, interfaces to external systems. Hybrid powertrain is used to provide electric traction to the vehicle and to charge the included battery. Battery provides power to electric motor. Major components of hybrid powertrain are Generator, Traction motor, High voltage battery, Inverters and other auxiliary units. The overall powertrain scheme is being discussed from functional safety perspective. Then methods for identifying hazardous situations that could result from malfunctioning behavior at the vehicle level is presented. Each function is analyzed from hazard perspective and all hazards are identified.

Micro Hybrid Systems are essentially first step towards the electrification of the powertrains. They are aimed at improving the fuel efficiency of the conventional gasoline and diesel power trains with conventional 12 V electrical system, and thus reduce the CO2 emissions as well. Various technologies like Engine Stop-Start, Intelligent Alternator Control, and Electrical Energy Management Systems are included in the bracket of micro hybrid systems. These system functions demand a totally different approach for managing the SLI battery, which is a total departure from the conventional approach. Particularly, the Alternator Shutdown function of Intelligent Alternator Control maintains a calibrated average level of State of Charge, which is typically around 80%, to ensure that the battery can accept more current, during the energy recuperation, which indirectly improves fuel economy.

Engine Stop/Start System (ESS) is a prominent subsystem in the Micro Hybrid Systems, and helps to reduce greenhouse gas emissions and fuel consumption. Fundamentally, ESS detects the idle running of the engine, and shuts it down autonomously, and allows the driver to restart the engine, with a routine action like pressing or releasing the clutch or brake pedal. When an engineer designs a system like ESS, typical approach to trigger the system functions is by establishing a sequence of events, detecting it, and enabling the triggers. Influence of the functions on other vehicle systems or vice versa is also considered, and system design is revised to achieve the functional safety. This results in a set of hard rules to be followed for the system functions to work.

The ever increasing demand of fuels for vehicles can only be met by use of alternate fuels like Compressed Natural Gas (CNG) and Hydrogen (H2). The 18 percent hydrogen enriched CNG fuel referred to as HCNG has the potential to lower emissions and is considered to be the first step towards promotion of a Hydrogen economy. While, automotive industry matures up with the usage of new engines, lubricant manufacturers are also moving on to the next stage by formulating oils to be used in gas engines such as CNG, HCNG etc. This paper presents the evaluation of gas engine oil on 6-cylinder heavy duty CNG engine using HCNG. The six cylinder engine was chosen due to its importance for urban bus transportation. The engine was optimized for using HCNG fuel. Initial performance of the engine using HCNG was compared vis-à-vis CNG and, thereafter, the engine was subjected to endurance test of 500 hours as per 8 mode engine simulated driving cycle.

Micro hybrid Systems are emerging as a promising solution to reduce the fuel consumption and greenhouse gas emissions in emerging markets, where the strict emission requirements are being enforced gradually. Micro hybrid Systems reduce the fuel consumption and greenhouse gas emissions in a conventional vehicle with 12 V electrical system, by optimizing the electrical energy generation, storage, and distribution, with functions like Intelligent Alternator Control, Engine Stop/Start, and Load Management. With the advent of Connected Car Systems, information about the vehicle is seamlessly provided to the customer not just through the Human Machine Interface systems within the vehicle, but to other mobile devices used by the customers.