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Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.

Light weight and Robust manufacturing technologies are always needed for transformation drive in the Automotive industry for the next-generation vehicles with greater Power to weight ratio. Innovations and process developments in materials and manufacturing processes are key to this light weighting transformation. Aluminium material has been widely used for these light weighting opportunities. However, aluminum joining techniques, characterized by their poor quality and consistency are limiting this transformation. This technical paper represents one of such case, where the part is made up of Aluminium through conventional casting route which has affected the laser weld quality due to poor casting soundness. This experiment explains in detail about the importance of Casting soundness for laser weld quality, weld penetration, strength etc., and the Product consistency.

Phosphating is the most preferred surface treatment process used for auto body sheet panel before painting due to its low-cost, easy production process, good corrosion resistance, and excellent adhesion with subsequent paint layer. There are different phosphating processes used for ferrous metal like zinc phosphating, iron phosphating, di-cationic & tri-cationic phosphating, etc. Among these phosphate coatings, the best corrosion resistance and surface adhesion are achieved by tri-cationic phosphate coatings (zinc-nickel-manganese phosphate). Many new technologies of phosphating are evolving. Key drivers for this evolution are increasing demand for higher corrosion resistance, multi-metal car body processing in same phosphating bath and sustainability initiatives to reduce the carbon footprints. We have evaluated two of these recent technologies.

Diesel engines are known for their excellent low-end torque, better drivability, performance, and better fuel economy. The increase in customer demands pushes to deliver higher power and torque along with fuel economy. This requirement puts a great challenge on the overall weight of the engine. This paper explains the holistic approach followed along with optimizing the rocker arm cover to achieve the weight target without compromising on durability and cost in the commercial segment 2.5-liter Diesel Engine. This paper presents a complete overview of the design and development of Rocker Arm (RA) cover to meet Strength, Durability, NVH and Aesthetic in Commercial Engine where base design is in aluminum which is mounted on cylinder head with a separate breather system. From aluminum the base design of Rocker arm cover is optimized to sheet metal where in there is reduction of 43% in weight and cost saving of 13%.

The Introduction of Corporate Average Fuel Economy (henceforth will be addressed as CAFE) regulations demand suitable technological upgrades to meet the significant increase in targets of vehicle fleet fuel economy. Engine Downsizing and Friction Reduction measures help in getting one step closer to the target. In a Conventional Oil Pump, the pump discharge flow and pressure are a direct function of operating speed. There is no control over lubricant flow which results in increased power and fuel consumption due to its unnecessary pumping characteristics irrespective of the actual engine demand. This paper discusses the introduction of a variable displacement oil pump (henceforth will be addressed as VDOP) that was adapted to a 1.5-liter 3 Cylinder Diesel Engine. This approach helps the system to reduce parasitic losses as the oil flow is regulated based on the mechanical needs of the engine. The flow is regulated with help of a solenoid valve which receives input from the ECU.

For meeting the stringent BS VI emissions in a 3-cylinder diesel engine the Exhaust after treatment system (EATS) was upgraded from a single brick DOC (diesel oxidation catalyst) to 2 brick DOC+sDPF (Diesel Particulate Filter) configuration. To meet the demands of emission regulation and sDPF requirements, changes were also required in the Fuel injection system. Major changes were done to the fuel injector and fuel pump. This paper primarily discusses the Fuel injector change from 1.1 to 2.2 family with changes in nozzle geometry, Nozzle tip protrusion (NTP), and injector cone angle and the effects on the emission and performance parameters. The various design values of NTP, cone angle, and Sac values are tested in an actual engine to meet the required power, torque and verified to meet NOx, HC, PM values as required by the new BS (Bharat Stage) VI regulation. Other boundary conditions are also checked - BSFC (Brake Specific Fuel Consumption), temperature, etc.

Body in White (BIW) of an automobile serves as the shell, on which all the components that make up a vehicle, are mounted. The BIW is an assembly of press formed sheet metal components. The sheet metal composition of each component varies based on the form and functionality requirement of that component. The resulting assembly has multiple weld joineries with dissimilar compositions. The weld integrity of the joineries is crucial in maintaining the geometrical and structural integrity of the BIW. The primary welding method used in BIW assembly is Resistance Spot Welding (RSW). The quality of the weld is an outcome of a combination of multiple weld parameters. These parameters are majorly estimated based on the joinery thicknesses and material combinations. Multiple welding and testing iterations are done to fine tune the parameters for an optimum weld joinery. This is a very tedious process which increases the process time of a BIW assembly.

Body in White (BIW) is an assembly of multiple sheet metal components. BIW is a major contributor to the dimensional and structural integrity of an automobile. The accuracy and precision of the BIW is influenced by multiple factors involved in the manufacturing lifecycle of the BIW, of which component development and assembly strategy are the most significant contributors. Weld fixtures are the tools used for accurately locating and holding, sheet metal components for joining. The primary motive of the locating and holding strategy is to arrest all degrees of freedom of a component. Geometric repeatability of the components is also of high importance. Component location is typically achieved by standardized locator pins that maintain the Principal Location Points (PLP). Mylars provided at Master Control Patches (MCP) ensure the resting and clamping of the component. Low volume BIW builds employ non-automated clamping methodologies, either with manual clamps or toggle clamps.

Design and development of high-pressure pipe involves number of design validation plans for robust design in diesel engine. The fundamental behavior of two-cylinder diesel engine with parallel stroke involves high vibration which generates stress on components mounted on crankcase resulting into earlier fatigue failure. In this paper, the innovative approach of using optimized design of vibration damper for resolving high vibration stress concerns in fuel system is discussed. The vibration dampers were designed meeting both performance and durability aspects in two-cylinder diesel engine applicable for both passenger and commercial vehicle. This paper highlights the design approach involving experimental stress measurements and design optimization based on part development feasibility.

Turbocharging of diesel engines have undergone various phases of technological advancements proving merits with engine performance. Since VGTs are finding their applications in many automotive engines, it is also crucial on finding out ways to extract maximum benefits from the system. Pneumatic actuated VGTs control the vanes positioning with the help of mechanical linkages and don’t prove good in transient response with relatively slower boost build up. The electronic controlled VGT operates with the aid of DC motor which is linked to the engine management system. The position sensor senses the current position of the actuator which is controlled by the engine management system for delivering the desired boost pressure. The eVGT system thus provides very quick response and accurate control of boost pressure in all the vehicle driving conditions.

To comply with the stringent future emission mandates of light-duty diesel engines, it is essential to deploy a suitable combination of emission control devices like diesel oxidation catalyst (DOC), diesel particulate filter (DPF) and DeNOx converter (LNT or SCR). Arriving at optimum size and layout of these emission control devices for a particular engine through experiments is both time and cost-intensive. Thus, it becomes important to develop suitable well-tuned simulation models that can be helpful to optimize individual emission control devices as well as arrive at an optimal layout for achieving higher conversion efficiency at a minimal cost. Towards this objective, the present work intends to develop a one-dimensional Exhaust After Treatment Devices (EATD) model using a commercial code. The model parameters are fine-tuned based on experimental data. The EATD model is then validated with experiment data that are not used for tuning the model.

The combustion phenomenon of diesel engines has got a very major impact on the performance and exhaust emission levels. Several important factors like engine components design, combustion chamber design, Exhaust gas recirculation, exhaust after treatments systems, engine operating parameters etc. decide the quality of combustion. The role of fuel injector is crucial on achieving the desired engine performance and emissions. Efficient combustion depends on the quantity of fuel injected, penetration, atomization and optimum timing of injection. The nozzle through flow, cone angle, no of sprays and nozzle tip penetration are the factors which lead to the selection of perfect injector for a given engine. This paper focusses on the selection of the best fit injector suiting the BS6 application on evaluating the performance and emission characteristics. Injectors used were with varying cone angles and NTP.

The combustion strategies play a key role in emission improvisation and noise reduction on diesel engines equipped for higher emission norus. This paper clearly discussed on the selection of various operating points for optimization and employing of proper calibration strategies like pilot strategy, Main injection timing, EGR type and rail pressure variation for best emission and noise output. Various optimization techniques have been implemented in our study. Since the pilot injection quantity as well as timing are varied in our paper, careful matrix formulation is required to determine the best optimum point. Around 340 points were obtained on varying pilot quantity and pilot separation sweep chosen at single engine speed and load for both the pilots. Out of the above points, 5 sensitive points were selected ensuring the sensitivity of the emissions and noise.

The contribution of engine borne noise is the major source of vehicle noise in diesel powered vehicles. The engine noise can be minimized by modification of engine components design and also with different acoustic abatement techniques. The research activities were carried out on 4-cylinder CRDe engine for SUV application. All the emission and performance parameters along with combustion noise was captured continuously for all the part load points from 1000 RPM to 2750 RPM with respect to the different road conditions and driving cycle. This paper targets on reducing the combustion noise at the noise prone zones only on the basis of the injection strategies ensuring no ill effect on the emissions and fuel economy. The first step was the reduction of rail pressure which helped noise levels to be reduced by almost 6 dB at noise zones. Main injection timing retardation was tried at all possible zones which influenced in considerable noise reduction at various zones.

In order to comply with the stringent future emission mandates of automotive diesel engines it is essential to deploy a suitable combination of after treatment devices like diesel oxidation catalyst (DOC), diesel particulate filter (DPF) and DeNox converter (Lean NOx Trap (LNT) or Selective Catalytic reduction (SCR) system). Since arriving at a suitable strategy through experiments will involve deploying a lot of resources, development of well-tuned simulation models that can reduce time and cost is important. In the first phase of this study experiments were conducted on a single cylinder light duty diesel engine fitted with a diesel oxidation catalyst (DOC) at thirteen steady state mode points identified in the NEDC (New European Driving cycle) cycle. Inlet and exit pressures and temperatures, exhaust emission concentrations and catalyst bed temperature were measured. A one dimensional simulation model was developed in the commercial software AVL BOOST.

Body in White (BIW) is one of the critical aggregates of an automobile. Establishing the quality parameters during body manufacturing is essential to achieve robust BIW structure. Spot weld integrity and dimensional accuracy are the two major quality parameters of a BIW. Weld integrity plays an important role in achieving dimensional accuracy and structural stability. Various combinations of sheet metals are joined together to form a BIW structure. Spot weld parameter selection is one of the critical activity and needs to be programmed for the various combinations of sheet metals. Weld parameter for the various combinations are calculated with the resistance of the joining sheet metals thicknesses. The calculated parameters are validated with the coupon test (or) peel test and it requires several iterations to establish weld integrity of the different combinations and the selected parameters get registered in the weld controller.

Diesel engines have occupied a significant position in passenger car applications in the present automotive sector. Turbochargers find a very prominent role in diesel engines of all applications in order to achieve desired power and better fuel economy. Gaining higher torque at lower engine speeds with low smoke levels is a very tough task with fixed geometry turbochargers due to availability of lower air mass resulting in higher smoke emissions. Variable geometry turbochargers are capable of providing better torque at lower speeds and reduced smoke emissions on Common Rail Diesel engines. The Variable Geometry Turbocharger types used in this study are straight profile nozzle vanes (sample A) and curved profile nozzle vanes (sample B). The curved profile vanes as seen in sample B results in reduced variation of circumferential pressure distortions.

The never-ending concern on the air quality and atmospheric pollution has paved way for more stringent emission legislations. Existing Diesel engine hardware face several problems on meeting the tough emission limits and they require more additional features to comply with the emission standards. The current research work throws light on the air path control approach to meet the Bharat stage 4 emission norms on 2.2 L Sports Utility Vehicle engine operating with EGR cooler and the techniques followed to meet the same emission norms without the application of EGR cooler which was successfully implemented on the vehicles enabling reduction of hardware. Also the migration of 2.2 L engine from 88 kW operating on Compression ratio 18.5 to 103 kW at a lower Compression ratio of 16.5 is a challenging process to achieve Nitrogen oxide emissions reduction at part loads.

Lean approaches are being implemented in various manufacturing facilities across the globe. The application of lean approaches are extended to Body proto build shop to maximize the efficiency of the shop with lesser floor space and optimized equipment. Weld fixture, Weld equipment and assembly tools are the major tools required essentially for proto BIW assembly. This paper explains how the Weld equipment planning was carried out with lean approaches and implemented effectively in proto body assembly shop. The implemented lean concepts are compared with Italy and Japanese proto body build makers to validate the frugal planning of the facility for the said intent. The implemented facility is capable of producing more than a model at a time. Weld parameter selection for weld gun, gun movement to the fixture with minimized change over time and movable weld gun gantry are the lean approaches implemented.

Several studies in the field of hedonics using subjective responses to gauge the nature and influence of odors have attempted to explain the complex psychological and chemical processes. Work on the effect of odors in alleviating driver fatigue is limited. The potential to improve road safety through non-pharmacological means such as stimulating odors is the impetus behind this paper. This is especially relevant in developing countries today with burgeoning economies such as India. Longer road trips by commercial transport vehicles with increasingly fatigued drivers and risk of accidents are being fuelled by distant producer - consumer connections. This work describes a two stage comparative study on the effects of different odors typically obtainable in India. The stages involve administration of odorants orthonsally and retronasally after the onset of circadian fatigue in test subjects. This is followed by a small cognitive exercise to evaluate hand-eye coordination.