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Fuel cells plays significant role in the automotive sector to substitute the fossil fuels and complement to electric vehicles. In the fuel cell vehicles fuel cell stack is major component. It is important to have a robust fuel cell model that can simulate the behaviour of the fuel cell stack under various operating conditions in order to study the functioning of a fuel cell and optimize its operating parameters and achieve the best efficiency in operation. The operating voltage of the fuel cell at different current densities depends upon thermodynamic parameters like temperature and pressure of the reactants as well factors like the state of humidification of the electrolyte membrane. A 1D model is developed to capture the variation in voltage at different current densities due to internal losses and changes to operating conditions like temperature and pressure.

The growing demand of fuel and cost saving on vehicle, today’s vehicle manufacturer are working on various weight reduction initiative in EV. Lighter weight vehicle have bigger challenges to meet NVH requirement. There are two types of EV called modified and adopted EV’s are commonly in use. The sub frame type of EV system comes under the category of modified EV. In this paper, a mounting system is studied and compared for a cradle type EV as well as sub frame or saddle type EV. MATLAB based optimization tools are used for parameter optimization. The focus is put on the optimization of mounting system location and stiffness for energy optimization, CoG and TRA-EA optimization. The best engine mounting system is compared and adopted based on simulation. 12 DOF studied to address high frequency resonance issues for a sub frame type EV. Finally robustness of the system is checked based on various simulation and optimization.

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.

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.

Steering system deliver a precise directional control to the vehicle chassis and ensure the safe driving at all maneuvers. Hydraulic power assisted system (HPAS) helps drivers to steer by boosting steering assistance of the steering wheel while retaining the road feel. HPAS performance is associated with the design characteristics of rotary valve, steering, suspension, kinematics, brake, tire, vehicle speed and load transfer. Thus a detailed power steering system model is absolutely necessary to evaluate and optimize the performance characteristics. However, many components of HPAS system are proprietary in nature so it is very challenging to get component characteristic of each sub-system for the complete power steering system model. Hence, it is very important to establish a technique to extract all such influencing characteristics with available test facility.

Nowadays, E- commerce and logistics business model is booming in India with road transport as a major mode of delivery system using containers. As competition in such business are on rise, different ways of improving profit margins are being continuously evolved. One such scenario is to look at reducing transportation cost while reducing fuel consumption. Traditionally, aero dynamics of commercial vehicles have never been in focus during their product development although literature shows major part of total fuel energy is consumed in overcoming aerodynamic drag at and above 60 kmph in case of large commercial vehicle. Hence improving vehicle exterior aerodynamic performance gives opportunity to reduce fuel consumption and thereby business profitability. Also byproduct of this improvement is reduced emissions and meeting regulatory requirements.

The customer expectations in the passenger car market are predominantly in the areas of engine/vehicle performance along with NVH refinement. In addition, continuously evolving regulatory emission and crash norms with system cost considerations bring out multiple challenges on to design engineers. One of the vehicle systems that has its footprints on all of the above requirements is the engine air intake system. In this paper, using multidisciplinary approach we discuss the impact of air intake system design of a 3-cylinder gasoline engine on different attributes of customer requirements. The primary function of the air intake system is to provide filtered air to the engine. However, this paper explains how requirements like engine performance, NVH refinement, regulatory and styling, durability, servicing and system cost are affected by intake system design parameters.

Vehicle Ergonomics is one of the most vital factor to be considered in vehicle design and development, as the customer wants a comfortable and performance oriented vehicle. An uncomfortable driving posture can lead to painful driving experiences for longer hauls. The control pedals viz. Accelerator, Brake and clutch pedal (ABC Pedals), are the most frequently used parts in the vehicle, their proper positioning with respect to human anthropology is of prime importance, from driver comfort viewpoint. The methodology currently used for optimizing ergonomics with respect to the positioning of pedals in a vehicle included; measuring anthropometric angles manually with the help of H-Point Machine, subjective jury analysis and through software like RAMSIS, JACK, etc. Manual measurement doesn’t give the flexibility of iterations for optimization. The subjective analysis is based on insinuations thereby, cannot be standardized.

In electric vehicles, the powertrain mounting system design has challenges different from conventional internal combustion engine (ICE) powertrains. Due to the absence of source noise, the customer predominantly experiences the buzz, squeak and rattle (BSR) noise. The 6 degrees of freedom (DOF) modal frequency target is less stringent than a three-cylinder or four-cylinder ICE powertrain. The durability loads in EV also differ due to less powertrain weight. In this paper, a study has been carried out about balancing all three main performance parameters of modal decoupling, BSR and durability through powertrain mount design optimization. The article shows that a carryover ICE powertrain mount has typical issues in Electric Vehicle (EV). A case study has discussed in detail how to manage those issues. Finally, it is concluded that a particular focus is required during an early stage of mount design to address these challenges for an EV.

Leaf springs are used for vehicle suspension to support the load. These springs are made of flat sections of spring steel in single or in stack of multiple layers, held together in bracketed assembly. The key characteristics of leaf spring are defined as ability to distribute stresses along its length and transmit a load over the width of the chassis structures. The most common leaf spring steels are carbon steels alloyed with Cr and micro-alloyed with Ti, V and Nb. The specific thermomechanical process and alloying elements result in specific strength and fatigue properties for spring steels. The unique properties which facilitate use of spring steel in leaf spring suspensions are ability to withstand considerable twisting or bending forces without any distortion. The microstructure of these steel determines the performance and reflects the process of steel manufacturing. The performance is mainly determined by evaluating fatigue life durability.

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.

As the automobile industry in India is growing fast and competitive, there is a need to design the vehicle and its parts at most cost effective. This paper gives the details of design optimization and cost effective methodology followed to develop a Single Stalk Combination Switch, without degrading the end user delight. This paper describes various design criteria affecting the combination switch design.

Today's automotive industry demands high quality component as well as system designs within very short period of time to provide more value added features to customers on one hand and to meet stringent safety standards on the other. To reconcile economy issues, design optimization has become a key issue. In the last few decades, many OEMs took to analytical tools like Computer-Aided-Engineering (CAE) tools in order to decrease the number of prototype builds and to speed up the time of development cycle. Although such analytical tools are relatively inexpensive to use and faster to implement as compared to the costly traditional design and testing processes: however, there are many variables that CAE tools cannot adequately consider, such as manufacturing processes, assembly, material anisotropy and residual stresses. Therefore, still smart measuring and testing techniques are required to substantiate the CAE results.

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.

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.

The recent vehicle development demands for electric powertrain as against conventional fuels engines. The electric powertrain offers advantages in terms of cleaner and quieter operations. In electric vehicle, the conventional engine is replaced by electric motor operated on batteries. Here, the conventional engine refers to those powered by diesel, petrol, CNG and some hybrid vehicles using fuel as primary source for power generation. Thus, the system design approach for mount also changes. At present, various approaches are being followed to mount electric powertrain like conventional pendulum type, with or without cradle, Common or different motor and electric box mountings etc. The electric powertrain differs from conventional powertrain in terms of weights, mass moment of inertia, torque, NVH requirements like Key in Key off, idling, low frequency vibrations etc. Thus conventional mount will not necessarily meet NVH requirements for Electric powertrains.

The necessity of hybrid vehicles and electric vehicles is well known by now for reasons like fossil fuel depletion, climate change, emission norms mandated by regulations etc. With the addition of electric motor, battery and associated power electronics, the cost of powertrain and hence the vehicle goes up, which is often a hindrance for OEMs and end-customers. With the objective to make a cost-effective strong hybrid, Tata Motors has approached this problem by taking economies of scale approach i.e. developing an add-on gearbox module, which can fit a family of cars, in a P3-off axis hybrid configuration to an electrically actuated AMT. This paper presents the preliminary simulations, which show this architecture yielding a reduction of fuel consumption by ~20% for a B-class sedan/compact SUV of ~1800kg and ~15% improvement in acceleration performance. Additionally, the design and packaging studies show the fitment possibility in a highly congested powertrain bay.

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.

Automotive suspension system forms the basis for the design of vehicle with durability, reliability 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 growing demand for light-weighting has culminated into numerous designs of rear twist beam suspension systems. However these designs drive their design flexibility by incorporating multiple welding joints into the suspension system. Welding joints helps in designing complex automotive systems. However, these welding joints bring in weak points as welding process itself degrades parent material and introduces areas with high tensile residual stresses. These areas with tensile residual stresses are susceptible to undergo fatigue failure. Thus, there is a need to improve welding process to mitigate harmful tensile residual stresses.

Lift axles of heavy commercial vehicles are deployed to handle increased payload. These axles of Commercial vehicles are made of low alloy carbon steel materials. Lift axles are designed in hollow condition for weight reduction opportunity. Two types of tube materials are used for the manufacturing of lift axles. These are either Cold Drawn Seamless (CDS) tubes or Hot Finished Seamless (HFS) tube material. The vanadium micro-alloyed steel grade, 20MnV6 is an excellent choice for the manufacturing of lift axles. The 20MnV6 has favorable mechanical properties for lift axles and also offers good weldability. However, lift axles made of 20MnV6 when manufactured in hot-finished condition, shows significant scatter in terms of durability performance. This requires further heat treatment of 20MnV6 to be deployed for reducing the scatter in the material properties to reduce scatter in durability performance and thus increasing the reliability of the lift axles.