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Diesel Engines are known for its low fuel consumption coupled with high specific power output. Downsizing the engines with turbocharging and common rail injection technologies are the recent trends in improving the efficiency and performance of diesel engines. It is very challenging to match the torque targets at low speed and power targets at high speed range of a diesel engines due to system hardware limitation. Torque at lower engine speed will improve a greater extent to the drivability of a vehicle. Formation of black smoke is a major problem in lower engine speeds due lack of air availability. The use of variable geometry, two stage turbocharging and four valves per cylinder are some of the solutions which make the task simpler, also involves additional cost and fundamental design changes. At the same time commonly used waste gate turbocharger for boosting the airflow, fails to deliver required air flow at lower engine speeds.

This paper is an attempt to compile a systematic approach which can be easily incorporated in the product development system used in the design and development of parking brake systems for passenger cars having rear drum brakes, which in turn can effectively reduce the lead time and give improved performance. The vehicle GVW, percentage gradient and maximum effort limits (as per IS 11852 - Part 3), tire and drum brake specifications were taken as front loading. This data is used for target setting of functional and engineering parameters, such as lever pull effort, lever ratio and angular travel of lever. Design calculations were performed to obtain theoretical values of critical parameters like lever effort and travel. The comparison between target and theoretical values give the initial confidence to the system engineer. Further, the outcome was taken to conceptualize the hard points of lever on vehicle for ergonomics.

A four-wheeled automobile during braking event in which left and right wheels of the vehicle are on different mu surfaces, has high chances of experiencing spin, which may lead to stability issues on vehicle. This paper intends to provide a mathematical approach to predict the deceleration at which vehicle will spin during braking in a differential mu surface, and determine the effect of influencing parameters on the extent of the vehicle spin tendency. This paper also provides a correlation between theoretical vs actual decelerations for vehicles to exhibit vehicle spin tendency. This paper helps in providing sufficient aid/tool for system designer to predetermine the vehicle spin at early level of system designs and make necessary amendments at initial stage of prototype development rather than late changes, to create a product which gives safe driving experience.

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.

Oil pump is one of the important engine parasitic loads which takes up engine power through crankshaft to deliver oil flow rate according to engine demand to maintain required oil pressure. The proper functioning of oil pump along with optimum design parameters over various operating conditions is considered for required engine oil pressure. Pressure relief passage is also critical from design point of view as it maintains the required oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfied performance and lubrication of various engine parts. Low oil pressure will lead to seizure of engine and high oil pressure leads to failure of oil filters, gasket sealing, etc. Optimization of pressure relief passage area along with other internal systems will also reduce the power consumed by the pump.

Oil pump is one of the important engine parasitic loads which takes up engine power through crankshaft to deliver oil flow rate according to engine demand to maintain required oil pressure. The proper functioning of oil pump along with optimum design parameters over various operating conditions is considered for required engine oil pressure. Pressure relief passage is also critical from design point of view as it maintains the required oil pressure in the engine. Optimal levels of oil pressure and flow are very important for satisfied performance and lubrication of various engine parts. Low oil pressure will lead to seizure of engine and high oil pressure leads to failure of oil filters, gasket sealing, etc. Optimization of pressure relief passage area along with other internal systems will also reduce the power consumed by the pump.

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.

The automotive industries around the world is undergoing massive transformation towards identifying technological capabilities to improve vehicle performance. In this regard, the engine dynamic torque plays a crucial role in defining the transient performance and drivability of a vehicle. Moreover, the dynamic torque is used as a visualization parameter in performance prediction of a vehicle to set the right engineering targets and to assess the engine potential. Hence, an accurate measurement and prediction of the engine dynamic torque is required. However, there are very few methodologies available to measure the engine dynamic torque with reasonable accuracy and minimum efforts. The measurement of engine brake torque using a torque transducer is one of the potential methods. However, it requires a lot of effort and time to instrument the vehicle. It is also possible to back-calculate the engine torque based on fuel injection quantity and other known engine parameters.

The air velocity achieved at driver and passenger aim point is one of the key parameters to evaluate the automotive air-conditioning system performance. The design of duct, vent and vanes has a major contribution in the cabin air flow directivity. However, visual appearance of vent and vane receives higher priority in design because of market demand than their performance. More iterations are carried out to finalize the HVAC duct assembly until the target velocity is achieved. The objective of this study is to develop an automated process for vane articulation study along with predicting the optimized velocity at driver and passengers. The automated simulation of vane articulation study is carried out using STAR-CCM+ and SHERPA optimization algorithm which is available in HEEDS tool. The minimum and maximum vane angle are defined as parameters and face level velocity is defined as response.

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.

Ride is an important attribute which must be accounted in the passenger segment vehicles. Excessive H point acceleration, Steering wheel acceleration, Pitch acceleration can reduce the comfort of the driver and the passengers during high frequency and low frequency rough road events. Excessive Understeer gradient, roll gradient, roll acceleration and Sprung mass lift could affect the Vehicle driver interaction during Steady state cornering, Braking and Step steer events. The concept architecture of the vehicle plays an important role in how comfort the vehicle will be. This paper discusses how to improve SUV ride performances by keeping handling performance attributes same or better than base vehicle. Multi Objective Optimization was carried out by keeping spring, bushing and damper characteristic as the design variables to avoid new system or component development time and cost.

Steering returnability while driving is one of the most important parameter which affects the drive pleasure and handling of a vehicle. Steering returnability refers to the automatic returning response of the steering wheel after taking a full turn while vehicle is being steered during driving. Evaluating steering response characteristics of any vehicle in a virtual environment at early stage of a product development saves significant development time and cost. Through this paper an attempt has been made to develop a methodology for selection of suspension hard points which influences steering returnability characteristics of a vehicle at an early product design stage. Conventionally, suspension kinematic parameters such as Caster angle, Steering axis inclination (SAI), etc. are iterated during vehicle design stage to achieve desired Steering returnability.

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.

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.

This paper presents a comprehensive model of a hydraulic power steering system for predicting the transient responses under various steering inputs. The hydraulic system model, which integrates together all fluid line elements and hydraulic components, is formulated using the MSC Easy5 software. A full vehicle model is developed in ADAMS/Car. Functional Mock up Interface (FMI), a tool independent standard is used for co-simulation of ADAMS and Easy5 Dynamic models. This paper describes a co-simulation methodology developed using FMI interface for full vehicle Simulations using hydraulic power steering. A virtual simulation scheme is developed to obtain the system transient responses and the results are compared with those measured from the tests. In general, the simulation results agree with those obtained from the tests under the same steering inputs and operating conditions.

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.

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.

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.

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.

Ride is essentially the outcome of coupled dynamics of various involved sub-systems which make it too complex to deal analytically. Tires, amongst these, are known to be highly nonlinear compliant systems. Selection of tires specifications such as rated tyre pressure, etc. are generally decided through subjective assessment. While experts agree that tyre pressure affects the attributes such as ride to a noticeable degree, the quantification of the change often remains missing. In the current work, vibration levels of various sub-systems relevant to ride in an SUV are measured for three different tyre pressures at different speeds over the three randomly generated roads. For the purpose, artificial road profiles of classes A, B and C are synthesized from the spectrum of road classes defined in ISO 8608:2016 and reproduced on a four-poster test rig.