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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.

In India, around 70 million people travel by public transport buses. With rising air pollution across cities, there is a need to safeguard passengers from inhaling polluted air. Contaminants in such polluted air could be fine to coarse dust (2.5 micron to 100 micron), exhaust gases (oxide of sulphur, nitrogen and carbon), total volatile organic compounds, bacteria and viruses arising out of covid-19 pandemic. Passengers commuting in buses are continuously inhaling air that is re-circulating through the Air Conditioning system (AC) and also comes in contact with multiple co-passengers and touch points. This air potentially carries a high dose of contaminants and inhalation of such air can lead to health issues. Vehicle manufacturers intend to provide clean air inside the vehicle cabin by configuring various Air Purification systems (AP) which reduce air contaminants in the closed space of a cabin.

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.

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.

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.

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.

The small commercial vehicle business is driven by demand in logistic, last mile transportation and white goods market. And to cater these businesses operational and safety needs, they require closed container on vehicle. As of now, very few OEM’s provide regulatory certified container vehicle because of constrains to meet inertia class of the vehicle. This paper focuses on design of a durable and extremely reliable container, made of the low-cost economy class glass fibre & core material. The present work provides the means to design the composite container for the N1 category of the vehicle. The weight of after-market metal container ranges between 300-350 Kg for this category of vehicle, which affects the overall fuel economy and emission of the vehicle. A detailed CAE analysis is done to design composite container suitable to meet inertia class targets and to achieve weight reduction of 30-40% as compared to metal container.

In the past five years, Indian cities have been consistently appearing in the list of top 15 world’s most polluted cities. Every day, a common man in India spends more than 2 hours on the road due to numerous reasons, thus exposed to inhale highly polluted air. Further, the passenger car users is exposed to ~ 6 times more polluted air as compared to ambient air reason being the air is recirculated through the air conditioning system. Prolonged exposure to such polluted/ recirculated air shows increasing trend in respiratory illnesses, breathing discomfort and fatigue. This paper discusses the key challenges involved in incorporating cabin air filter as cabin air quality enhancer in current mobility solutions.

Severe air pollution in cities caused largely by vehicular emissions, which requires urgent remedial measures. As automobiles are indispensable modes of personal and public mobility, pre-emptive efforts are necessary to reduce the adverse effects arising from their operation. A significant improvement in air quality can be achieved through large-scale introduction of vehicles with extremely low emission such as hybrid-electric and zero emission vehicles. Range extension of electric vehicles (EVs) is also of utmost importance to alleviate the handicap of restricted mileage of purely plug-in EVs as compared to conventional vehicles. This paper presents development of a polymer electrolyte membrane (PEM) fuel cell stack used for the range extender electric vehicles. The Fuel cell stack for range extender vehicle operated in a dead end mode using hydrogen and air as open cathode.

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.

Vehicle manufacturers strive hard to achieve best in class fuel economy. Apart from light weighting of the structures, driveline optimization and reduction of tire rolling resistance, tapping of parasitic losses is also important and helps to optimize the design of auxiliary power consuming systems. One of such system studied in this work is power steering system. The effect of parasitic losses on fuel economy is predominant for small commercial vehicle compare to heavy vehicles. The evaluation of deterioration in the fuel economy due to implementation of power steering system on one of the small commercial vehicle is carried out using multiple virtual simulation tools. Virtual route profile is modelled using longitude, latitude and altitude data captured through GPS and steering duty cycle is mapped in terms of steering rotation angle. A system level model of hydraulic power steering system is developed.

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.

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.

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.

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.

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.

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 emerging technology trend, there is continuous demand for increase in engine performance in terms of power & torque while providing competitive fuel efficiency. Understanding and fulfillment of complex customer requirements with affordable technology is extremely challenging. In order to meet potential conflicting needs and offer ‘fun to drive’ experience to customers, Tata Motors has developed first in segment turbocharged gasoline MPFI engine. Further in order to create market differentiator, multi drive modes were introduced as segment first feature. The boosted compact 1200 cc engine while developing 90 Ps power, delivers 140 N-m torque over a wide range of 1500-4000 rpm, best suited for Indian drive conditions. This performance boost is nearly 40% over and above performance of comparable NA engine without any compromise on vehicle level fuel efficiency.