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Automotive suspension system forms the basis for the design of vehicle with durability, reliability, dynamics and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The current focus in automotive industry is to reduce the weight of the automotive parts and components without compromising with its static and dynamic mechanical properties. This weight reduction imparts fuel efficiency with added advantages. High-Strength Low Alloy steel (HSLA) offers optimum combination of ductility, monotonic and cyclic mechanical properties. Furthermore, welding processes offer design flexibility to achieve robust and lightweight designs with high strength steels.

Environmental regulation, operating cost reduction and meeting stringent safety norms are the predominant challenges for the automotive sector today. Automotive OEMs are facing equally aggressive challenges to meet high fuel efficiency, superior performance, low cost and weight with enhanced durability and reliability. One of the key technologies which enable light weighting and cost optimization is the use of fiber reinforced polymer (FRP) composite in automotive chassis systems. FRP composites have high specific strength, corrosion and fatigue resistance with additional advantage of complex near net shape manufacturing and tailor made properties. These advantages makes FRPs an ideal choice for replacing conventional steel chassis automotive components. However, FRP’s face challenges from operating environment, in particular temperature and moisture.

Hybridization of vehicle drive train is an important step to increase energy security, reduce crude oil import, improvement of air quality and GHG reduction. Heavy traffic congestion poses a great challenge in improvement of fuel economy. Nowadays urban climatic condition forces the passenger to keep air-conditioning (AC) on; thus further decreasing the fuel economy. In a typical urban drive; the vehicle commutes with low speed forcing IC Engine to run in its low efficiency operational points. Further it is characterized by frequent start-stop and crawling. It has been observed that the power consumption for AC is comparable to that required for the vehicle propulsion. Hence the AC on condition with propelling vehicle demands higher power from engine creating a challenge for fuel economy improvement.

Recycle, Reuse, Repair is an established process for sustainability. There are many ways in which cutting tools can be recycled. Be it by reshaping a used up throwaway type tool [1] or by redesigning a tool holder for the use of unused cutting edges [2]. This paper explores the possibility of reuse of HSS drills that are used for making long oil holes in automobile parts like crankcase (cylinder block), cylinder head, crankshaft, etc. Design/manufacture of such drills is peculiar by virtue of their size and length and are also known as thick web high helix drills. Making of oil holes entails use of drills that are 500 to 600 mm long depending on the size of the component. In most of the long oil hole drilling operations, a limited portion of the drill is useable. This is because there is a possibility of fouling of the holding elements with guiding element, or with the part being drilled and the chance of accidental damage to part or machine.

Small goods carrier and passenger vehicles powered by Naturally Aspirated (NA) Direct Injection (DI) diesel engines are popular in Indian automobile market. However, they suffer from inherently high radiated noise and poorly perceived sound quality. This paper documents the steps taken to reduce the radiated noise level from such an engine through structural modifications of major noise radiating components identified in the sound power analysis. The work is summarized as follows; Baseline radiated noise measurements of power train and identification of major noise sources through sound intensity mapping and noise source ranking (NSR) in an Engine Noise Test Cell (ENTC) Design modifications for identified major sources in engine structure Vehicle level assessment of the radiated noise in a Vehicle Semi-Anechoic Chamber (VSAC) for all the design modifications. A reduction of 7 dB at hot idle and 4 - 8 dB in loaded speed sweep conditions was observed with the recommended modifications.

A hydraulic-assisted power steering system on a vehicle has a steering pump which is directly driven from the engine continuously. In real world, the assistance from the steering pump is useful only while maneuvering. During a typical highway drive, assistance from this power steering pump remains unused for majority (76%) of the time; although the continuously rotating power steering pump keeps consuming energy from the engine. An electronic controller has been provided for the electro-magnetic pairing device of the power steering pump in order to provide assistance for steering based on driver demand only. The electromagnetic pairing device integrated on the steering pump can be made to engage/disengage based on the driver demand through the electronic controller.

For sustainability in automobile manufacturing, recycle, reuse, and repair of used up cutting tools is now an established process. Although many types of tools were designed for one time use and then throw, an increasing awareness of the impact on the natural resources have made manufacturers to put some of these back to use or sell it back to suppliers who have put up a mechanism to extract the elements e.g. Tungsten and use it for manufacturing of new tools. There are many ways in which cutting tools can be recycled. Be it by reshaping a used up throwaway type tool [1], by redesigning of a tool holder for the use of unused cutting edges [2] or reusing short length drills that are used in making of long oil holes in crank case, cylinder head, cam shaft or connecting rods [3]. This paper demonstrates successful use of used up crankshaft grinding wheels.

S.A.V.E. (SOLAR-ASSISTED VEHICLE ELECTRICAL SYSTEM) is a microcontroller-based closed loop system designed to optimize the duty cycle of alternator in conventional vehicle electrical system. This has been done by integrating a SOLAR PANEL on the rooftop of a popular hatchback. The SOLAR PANEL supplies continuous power to battery for charging thereby reducing alternator duty cycle. Consequently, in order to optimize/control alternator functioning based on demand, a microcontroller has been incorporated. S.A.V.E. consists of a microcontroller which senses the instantaneous electrical load (in terms of current & voltage drawn) from battery. The controller using the intelligent algorithm keeps on checking this real-time consumption with the threshold values & decides when to activate/deactivate alternator. Thus with this controller, a) reduction in actual CO₂ emission & consequent, and b) 6% improvement in vehicle fuel efficiency has been achieved.

Sustainable development is a very complex concept involving several inter-related issues and concerns. Globalization has given a new dimension to social, economic and environmental development associated with the perceived responsibilities and growth indicators. Both developing and developed countries have the opportunities to exploit comparative advantages in the changing economic, social and environmental scenario while targeting sustainable growth together with expansion of the business prospects. Every region perceives these opportunities with different notion. There is a plethora of indicators for assessing sustainability. However, assessment criteria, prioritization and trade off for a given sustainability parameter against the other could be very complex while evolving transport growth model in emerging economies.

The crankshaft is the component which transmits dynamic loads from cylinder pressure and inertial loads in engine operating conditions. Because of its crucial importance in functioning of engine and requisite to sustain high dynamic and torsional loading, crankshaft fatigue life is desired to be higher than the predicted engine operating life. Performance of the crank train in diesel engine applications largely depends on the components of its mass elastic system. Flywheel is one such component whose design affects the life of crankshaft. In the present study, the crank train comprising of torsional vibration damper, crankshaft and flywheel along with clutch cover is considered for analysis. Crankshaft dynamic simulation is performed with multi body dynamics technique, fatigue safety factors of crankshaft are calculated with dynamic loads under engine operating conditions.

In today's scenario, most of the OEMs use manual transmissions with synchronizer gear shifting system for ease of gear shifting. It gives very high fuel efficiency. Gear shifting is a customer touch point, hence it is very important to select adequate synchronizer capacity so that it will perform in better and last longer. To test the synchronizers, there are many test methods which give the idea about life of synchronizer and its performance, in different conditions. Regular synchronizer rig tests consume lot of time in deriving the results. So it is very important to find out a way which will give same results within short time period. To carry out the short time test or accelerated test, we need to understand the effect of various factors like reflected inertia, drag torque, differential speed, synchronizing time, and gear shifting force on synchronizer capacity.

IC Engine manufacturers are constantly in pursuit of better sealability of cylinder head and engine block interface for meeting performance and durability targets. In order to overcome variation in torque - tension characteristics of cylinder head bolt because of friction variations, yield based clamping are being extensively adopted. Current study is done on torque - tension characteristics of a cylinder head bolt with a controlled quality. The paper enumerates the experimental setup representing a sub 1 liter all aluminum engine's head-block joinery. Studies on torque - tension characteristics of cylinder head bolt and the effect of sealing interface using a cost effective single layer steel gasket are being discussed in the paper. Subject work has led to a successful implementation of angular torque parameters on head bolts to meet functional and durability targets.

The authors of this technical paper conceptualize and illustrate a powertrain architecture for a hybrid electric vehicle coupled with a unique strategy to reduce a real life problem of driving in snail paced traffic. This architecture utilizes a relatively low powered hybrid electric prime mover that is generally used in mild hybrid vehicles, in an arrangement similar to a parallel hybrid system. Here, the electric machine is mounted on the input shaft of the gearbox and the clutch is actuated automatically through an Automated Manual Transmission (AMT) system. Therefore, it is possible to completely disengage the engine from the driveline and drive the vehicle independently through an appropriately sized electric prime mover. The high gear ratio between the drivetrain and the electric prime mover at lower gears can be leveraged to provide low velocity electric creep mode during which the vehicle can function as a pure Electric Vehicle (EV) while engine remains off.

Today’s competitive market demands for low cost passenger cars with lighter, smaller size, peppy response and fuel efficient engines and having world class NVH refinement levels. For such requirements, it is essential to optimize the product starting from the design conceptual stage, considering all performance aspects. Generally, three cylinder engines, due to less reciprocating masses, compared to four-cylinder engine, are said to be fuel efficient for the same capacity. Nevertheless, NVH problems caused by inherent imbalance forces and couples remain as drawback of the three-cylinder engine. However, through optimal design of the crank train, control of cylinder to cylinder pressure variation, stiffening of the engine structure, optimizing the integration with a vehicle through proper design of mounts, NVH refinement levels can be improved.

Aerodynamics performance evaluation of passenger cars is important during early vehicle development phase as it influences fuel economy, vehicle stability and drivability. Usually during initial styling phase, scale model is prepared and tested in wind tunnel to check aerodynamic performance like drag coefficient and these are used to predict aerodynamic performance of full scale model as testing on full scale model is costly and time consuming. To ensure its correctness, it is important to understand difference in physics from scale model to full scale model. In predicting full vehicle aerodynamics performance from scale model assessment; importance of Reynolds number, effect of geometric scaling on flow i.e. flow separation and wake zone change needs to be understood and addressed. This paper discusses about effect of scaling on aerodynamic flow behavior and drag.

OEMs are seeking to develop vehicle light weighting strategies that will allow them to meet weight and fuel economy targets hence increasingly shifting their focus towards incorporating lighter material solutions at mass produced scales. Composites are seen by automotive manufacturers as the solution to lightweight vehicles without affecting their performance. More and more parts are made of short fiber reinforced plastics (SFRP) as well as continuous fiber composites. However, replacing metals by composites requires a new design approach and a clear understanding of the composite behavior. This paradigm however requires a dedicated tool for composite design in order to take into account the specific composite behavior. Traditional design tools are not able to state accurately the composite material behavior and sometime leading to use high safety of factors and lack of confidence in the design.

Ever tightening emission limits and constant pressure for increasing engine power are resulting in increased engine operating temperature. This coupled with continuous drive for fuel economy improvement because of the stiff competition are forcing OEMs to explore alternative cooling solutions resulting in less power take off and quick response as cooling requirement shoots up. Aim of this paper is to analyze the relative benefits of incorporating a new cooling fan drive system concept over conventional viscous fan driven cooling system with step-less variable speed control independent of engine speed variation. Hydraulic fan drive system control fan rpm based on the fluid temperature as compared to air temperature in viscous coupling fan drive system. HFD system provides quick response when increase in coolant temperature is observed. HFD system in this way provide more control on fan rpm.

The present work focuses on optimization of gear shift pattern of an AMT vehicle to improve its NVH performance without causing any adverse effect on any other vehicle performance attribute. The vehicle which was identified with the structural body resonance at low frequency had discomforting boom noise in a particular engine rpm zone and at corresponding vehicle speed. With the initial shift pattern (will be referred as V1 gear shift schedule), the gear shifts were calibrated such that when vehicle is driven in the city with 20 to 60 kmph speed, the vehicle operated mostly in the best fuel economy zone but it used to pass through structural resonance frequency. This resulted in the presence of continuous boom leading to an unpleasant driving experience. In order to avoid the presence of boom noise during city driving, the gear shift points were optimized (will be referred as V2 gear shift schedule) such that the vehicle did not operate in affected engine speed range.

In the modern era of automotive industry, occupant comfort inside the cabin is a basic need and no more a luxury feature. With increase in number of vehicles, the expectations from customers are also changing. One of the major expectations from real world customers is quick cabin cooling thru all seasons, particularly when the vehicle is hot soaked and being used in summer conditions. Occupant thermal comfort inside the vehicle cabin is provisioned by a mobile air conditioning (MAC) system, which operates on a vapor compression-based cycle using a refrigerant. The main components of a direct expansion (DX) based MAC system are, a compressor, condenser, evaporator, and expansion valve. Conditioned air is circulated inside the cabin using a blower, duct system and air vents. The AC condenser is the most critical component in AC circuit as it rejects heat, thereby providing for a cooling effect inside the cabin.

Vehicle aerodynamic design has a critical impact on fuel efficiency of the vehicle. Reducing aerodynamic wind resistance of the vehicle's exterior shape and reducing losses associated with requirements for engine compartment cooling through vehicle front openings plays key role in achieving desired aerodynamic efficiency. Today fairly large number of computational fluid dynamics (CFD) simulations are being performed during the vehicle aerodynamic design and development process and it is rapidly increasing day by day. Vehicle aerodynamic design and development process involves mainly aerodynamic shape development, aerodynamic optimizations of vehicle external components (side view mirror, spoilers, underbody shield etc.) and number of” what if studies during preliminary design process. Licensing costs of the available commercial CFD simulation solver has significant impact on product development cost when numbers of aerodynamic simulations expand.