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The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.

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.

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.

The fuel economy of heavy commercial vehicles can be significantly improved by reducing the rolling resistance of tires. To reduce the rolling resistance of 6×4 tractor, the super single tires instead of rear dual wheel tires are tried. Though the field trials showed a significant increase in fuel economy by using super single tires, it posed a concern of road safety when these tires blowout during operation. Physical testing of tire blowout on vehicle is very unsafe, time consuming and expensive. Hence, a full vehicle simulation of super single tire blowout is carried out. The mechanical properties of tires such as cornering stiffness, radial stiffness and rolling resistance changes during the tire blowout; this change is incorporated in simulation using series of events that apply different gains to these mechanical properties.

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.

Engine performance and emission control are key attributes in the overall engine development in which sealing of the mating components plays an important role to achieve the same. Rubber gaskets are being used for sealing of different Internal Combustion (IC) engine components. Gasket sealing performance needs to be ensured at initial development stage to avoid the design changes at the later part of development cycle. Design changes at later stage of development can potentially influence parameters like optimization, cost and time to market. Demand of utilization of virtual tools (front loading) is growing with the increasing challenges like stringent product development cycle time and overall project cost. This paper describes a procedure to simulate the rubber gasket and groove for different material conditions (dimensional tolerances). This entire simulation is divided into two phases. In the first phase of the simulation, Load Deflection curve (LD curve) is established.

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.

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.

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.

Diesel oxidation catalysts (DOC) combined with NOx adsorbers and passive selective catalytic reduction (SCR) systems have demonstrated effectiveness in achieving high conversion efficiencies for CO, HC, and NOx emissions. This integrated exhaust after-treatment system has shown its efficiency in meeting the demanding BS6 Real Driving Emissions (RDE) standards. However, the assessment of emissions at the end of the system's life reveals a decrease in the conversion efficiency of aged exhaust systems, particularly affecting NOx, HC and CO emissions. Factors such as thermal aging and catalyst poisoning are identified as key contributors to the degradation of the after-treatment performance. This paper elucidates correlation methodologies applied to aged Lean NOx Trap (LNT) exhaust after-treatment systems. These methodologies aid in understanding the aging behavior of LNT samples and devising strategies to enhance the emissions performance aged samples during the end-of-life tests.

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.

Enriched ventilation and driver assistance systems which plays vital role in human thermal comfort and safety, are now necessities for the whole automotive sector. For faster cabin thermal comfort, air circulation around occupant’s body reveals higher cabin comfort index. In India natural and forced ventilation system is predominantly used in commercial vehicles as an economical solution for achieving interim cabin comfort over air conditioning system. Presently used forced ventilation system consist of electrically driven blower motor to remove stale air around human body which is adding alternator load and thus affects fuel economy. Remarkably, 22% of such auxiliary electrical load is taken by electrical components from engine generated power. In order to enhance cabin thermal comfort and conceivably reduce power usage, an effective air flow control system is need of hour.

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.

With ever increasing population growth and increase in per capita income, there is a lot of demand on energy requirements. Also due to depletion in fossil fuels, rocketing fuel prices and CO2 emissions standards, it is imperative to find solutions which are cost-effective and from sustainable energy sources. Being in the sunny tropical belt, India has high solar insolation, and so it should adopt a policy of developing solar power as a dominant component of the renewable energy mix. This paper describes the best possible ways to use solar energy for automotive application. This paper explains various types of photovoltaic (PV) technologies - crystalline and thin film solar cells for automotive use. A medium sized sedan vehicle with mild hybrid technology and roof mounted PV panel has been used for all experiments. The paper describe the benefits and limitations of each PV technology with experimental measurement and payback period analysis.

Small commercial vehicles (SCVs) are the drivers of a major part of India’s indirect economy, providing the most efficient means of transport. With the introduction of BS-VI norms, some major overhauls have been done to the SCV models to meet BS VI norms in challenging timeline for early market entry. This forced to automotive designers towards challenge of cost competitiveness as well as refinement level to survive in this competitive market. This paper explains the systematic approach used to overcome challenges of higher tactile vibrations, higher in-cab noise because of BS VI requirement in 2 cycle engine required for small commercial vehicle. The solutions were need to be worked out without compromising the other performance attributes like total cost of ownership, fuel economy, ease of servicing and cost effectiveness.

Today, most vehicles in developing countries are equipped with air conditioning systems that work with Hydro-Fluoro-Carbons (HFC) based refrigerants. These refrigerants are potential greenhouse gases with a high global warming potential (GWP) that adversely impact the environment. Without the rapid phasedown of HFCs under the Kigali Amendment to the Montreal Protocol and other actions, Earth will soon pass climate tipping points that will be irreversible within human time dimensions. Up to half of national HFC use and emissions are for the manufacture and service of mobile air conditioning (MAC). Vehicle manufacturers supplying markets in non-Article 5 Parties have transitioned from HFC-134a (ozone-safe, GWP = 1400; TFA emissions) to Hydro-Fluoro-Olefin, HFO-1234yf (ozone-safe, GWP < 1; TFA emissions) due to comparable thermodynamic properties. However, the transition towards the phasing down of HFCs across all sectors is just beginning for Article 5 markets.

Modern day diesel engines use systems like Exhaust Gas Recirculation (EGR), Variable Geometric Turbo Charger (VGT), inlet throttle for air regulation, multiple injection strategies, high pressure rail systems for fuel regulation to optimize the combustion for meeting the strict emission and fuel consumption demands. Torque based ECU structures which are commonly used for diesel engines require a large amount of calibration work. Conventional manual methods for emission and fuel consumption optimization (Full factorial or Line search method) results in increased test bed usage and it is almost impossible to use these methods as the number of parameters to optimize are very high. The conventional DoE tests have been limited by the necessity of calibration engineer’s expertise and manual prescreening of test points to be within thermal & mechanical limits of engine systems. This subsequently leads to excessive screening of variables; which is time consuming.

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.

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.

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.