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Unfavorable climates, fatigue, safety & deprived sleep of driver’s leads to use of AC system for their quick thermal comfort during night with engine ON. This scenario is very critical from a human’s safety & vehicle functionality point of view. This also consumes an additional 10-15% of fuel requirements in AC running conditions. So, to address the social problems of driver’s sleep and pollution-free environment by reducing the use of fossil fuels, there is a need for alternative techniques for air cooling which work during engine OFF condition. Various alternative options for air cooling have been reviewed. Accordingly, the packaging flexibility of phase change material (PCM) technology makes it easy to implement, yet effective usage of large quantity stored PCM, needs optimization. This paper proposes a design of a hybrid air conditioning system for sleeper commercial vehicles using a combined conventional compression and phase change material.

The vehicle pull (sideways) is a complex outcome of many parameters in an automobile vehicle. This is mainly due to steering, suspension, brake, wheels and chassis parameters. The road conditions like road camber also plays an important role in vehicle pull behavior. All efforts are put in design and manufacturing processes to maintain controlled vehicle pull in normal driving condition. Even though normal vehicle pull seems to be in acceptance limit (subjectively), its intensity increases many folds at the time of harsh braking. In these kind of panic situations where driver firmly holds on the steering wheel, it is expected that the vehicle should stop without deviating too much sideways from its intended straight line path to avoid any kinds of accidents. This work is an outcome of systematic study carried out to understand the root cause of brake pull as a field complaint on current production vehicles and adopting best possible solutions to minimize the brake pull.

The sunrise vision for hydrogen economy lies in efficient, lightweight and durable devices which can convert hydrogen energy into electrical energy. Proton Exchange Membrane fuel cell (PEMFC) is a key hydrogen energy conversion system for transport sector. The efficiency and durability of PEM fuel cell largely depends on cathode electrode and membrane and Bipolar plates (BP Plates) plays an important role in it. BP plates perform the important functions of transporting fuel gases to reactive sites, collecting charges and thus conducting electricity from cell to cell, moisture adjustment of membrane, transport of produced water and provides essential mechanical strength to fuel cell stack. It makes BP plates the backbone of PEM Fuel cell power stack. For BP plates to perform intended functions, it is highly desirable BP plates to possess excellent properties on corrosion resistance, electrical conductivity, thermal conductivity, water wettability, weldability and formability.

Reckoning today's environmental rules, legislative regulation and market requirements- the automotive industry of late has witnessed an increased vigor and enthusiasm by auto makers towards electrification of vehicles across all platforms in a bid to improve fuel economy and performance. Hybridization of a vehicle often involves the use of expensive high performance motors and large battery packs. However due to the challenges associated with the packaging of bulky battery and motor systems in existing drive train, mild hybrid systems have been preferred over strong or full hybrids especially in current production models as they don't entail any major change in architecture and the reduced battery size, both of which provide for easier packaging of components.

Vehicles have a wide range of resonance band due to design nature & characteristics of its aggregates. First order, vehicle speed dependent, wheel disturbance due to wheel imbalances can result in excitation of different vehicle aggregates. Steering wobble refers specifically to first order road wheel excitation effects, in frequency range of 10-16 Hz, that manifest themselves as significant steering wheel torsional vibrations at highway speeds i.e. at the range of 80 km/h to 120 km/h on smooth roads. The tire, being an elastic body analogous to an array of radial springs, may exhibit variations in stiffness about its circumference; hence, it may vibrate at different frequencies due to wheel imbalance. This paper introduces dynamic steering wobble analysis methodology either using vehicle speed at Discrete (individual speeds) or by Sweep (low to high speed) method to investigate steering wobble in the virtual environment using the full vehicle MBD model.

The automotive industry is facing a challenge as efficiency improvements are required to address the strict emission norms which in turn requires high performance downsized, lightweight IC engines. The increasing demand for lightweight engine needs high strength to weight ratio materials. To meet high strength to weight ratio, castings are preferable. However due to strength limitations for critical crankshaft applications, it forces to use costly forgings such as micro alloyed forging steel and Martensitic (after heat treatment) forging steel. To reduce the cost impact, high strength Austempered Ductile iron (ADI) casting is developed for crankshaft applications to substitute steel forgings. Austempered Ductile Iron is having an excellent mechanical properties due to aus-ferritic structure. The improved properties of developed ADI Crankshaft over steel forged crankshaft offers additional weight advantage.

Corrosion in automotive industry is broadly categorized into cosmetic & perforation corrosion. Cosmetic corrosion comprises of superficial red rust which is deleterious to the overall aesthetic appeal of the vehicle but can be rectified. Perforation corrosion involves complete erosion of the panel, compromising structural integrity of the respective part. Perforation corrosion demands part replacement. In order to tackle this menace, automotive OEMs have formulated varied corrosion strategies in terms of selection of appropriate substrate, part design & surface protection scheme. Validation of various corrosion strategies become pivotal during the development phase of various parts and assemblies. Traditionally, Salt Spray Test (SST) has been used to determine corrosion life of materials/parts/assemblies. This test however does not simulate real-world conditions.

Structural automotive components are subjected to fatigue damage under cyclic stresses and strains. The fatigue damage initiates at stress levels lower than the elastic limit of the material and results in cracks. The Initial fatigue cracks are difficult to detect, such cracks can develop rapidly and cause sudden and brittle failure in structures. Many structural automotive components are fabricated involving weld induced local conditions such as geometry of weld toe and localized tensile residual stresses. These conditions are favorable for initiation of fatigue damage at weld toe. In current work, sever plastic deformation (SPD) which is based on high frequency impact treatment using ultrasound energy was applied on weld toe of representative weld joints. The effect of SPD on weld toe geometry modification, microstructure and residual stresses were evaluated. Microscopic and X-ray diffraction techniques were used to study the effects of SPD.

A lightweight multi-material combination of steel and aluminium alloy (Al) is becoming a novel approach towards environmentally sustainable transport systems. Studies show that 10% reduction of vehicle weight results into 3-7% reduction in specific fuel consumption in IC engines and a 13.7% improvement in electric range for electric vehicles. However, dissimilar welding of Al/steel is a key challenge because of incompatible thermo-physical properties (melting point, thermal conductivity, and coefficient of thermal expansion) and low miscibility between Al and steel. The formation of brittle and hard Al-steel intermetallic compound (IMC) at the joint interface is the major concern for dissimilar welding of Al/steel. In this work, efforts are made to check the feasibility of Ni interlayer to control IMC formation at the interface of Al/steel dissimilar welded joint. Resistance spot welding is used to join low carbon steel CR01 and Al AA6061-T6 with pure Ni interlayer.

The usage of forging a preformed, near net shape, compacted and sintered metal powder has been widely accepted since the eighties and is now one of the mainstays for producing Connecting rods in North America. However, its use in Indian subcontinent is limited as its counterpart i.e. conventional steel forging is still the most dominant. Powder metallurgy route has many advantages like good dimensional accuracy; minimum scattering of weight etc. Despite these advantages, the Powder metallurgy process is still not preferred predominantly due to technical (endurance) and infrastructural limitations. This work envisages combining the benefits of powder metallurgy process with the required mechanical properties viz. tensile and fatigue strength alongside design modifications to meet the requirements of a connecting rod for a 2-cylinder diesel engine. The connecting rods met the fatigue life at the required FOS equaling the performance of a conventionally forged connecting rod.