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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 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.

Current Air Conditioning (AC) system uses hydrofluorocarbons (HFC) as refrigerant to transfer heat from cabin and cool the passengers. However, most refrigerants used today have severe environmental effects due to high global warming potential leading to global warming effects. Montreal Protocol and Kigali amendment calls for all nations to reduce refrigerant usage and transport sector being one of the main consumer of refrigerant, regulations regarding refrigerant usage and emission are becoming more stringent day by day. In this paper, a novel air-cycle refrigeration system has been designed and also tested for passenger vehicle applications. Automobile industry in developed countries has pivoted to R1234yf refrigerant for the most part, and has also rolled out R744 refrigerant for mass production to limited extent, which are in much lower Global warming potential (GWP) range than R134a.

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.

This paper explains about the design & development of IHX for HCVs segment and vehicle level validation to get the actual benefits with this technology. Moreover, the data observed during vehicle testing also indicates the improvement in AC System Performance. This experiment was done on HCV platform vehicle with multiple actual test conditions with two designs of IHX. Final result shows the optimized AC system design to achieve better efficiency.

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.

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.

Nowadays automotive cabin comfort has become a necessity rather than an optional feature, with customers demanding more comfort features. Thermal comfort becomes an essential part of this expectation. Since steering wheel is the first surface that the driver will touch once he enters the vehicle, maintaining thermal comfort of steering wheel becomes important, especially in tropical countries like India where a car parked in hot weather can get significantly warm inside. In this work, two design concepts for automotive steering wheel thermal control based on thermoelectric effect are depicted along with a detailed mathematical model. Thermoelectric coolers were selected for this purpose as it is solid state, compact & scalable solution to achieve rapid cooling rates. This was the desired feature expected from an integration standpoint in automotive architecture.

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.

Brake system design is intended to reduce vehicle speed in a very short time by ensuring vehicle safety. In the event of successive braking, brake system absorbs most of vehicle’s kinetic energy in the form of heat energy, at the same time it dissipates heat energy to the surrounding. During this short span of time, brake disc surface and rotor attains the highest temperatures which may cross their material allowable temperature limit or functional requirement. High temperatures on rotor disc affects durability & thermal reliability of the brake rotor. Excessive temperature on brake rotors can induce brake fade, disc coning which may result in reduced braking efficiency. To address the complex heat transfer and highly transient phenomenon during successive braking, numerical simulations can give more advantage than physical trials which helps to analyze complex 3D flow physics and heat dissipation from rotors in the vicinity of brake system.

In previous work, AC Compressor Cycling (ACC) was modeled by incorporating evaporator thermal inertia in Mobile Air Conditioning (MAC) performance simulation. Prediction accuracy of >95% in average cabin air temperature has been achieved at moderate ambient condition, however the number of ACC events in 1D CAE simulation were higher as compared to physical test [1]. This paper documents the systematic approach followed to address the challenges in simulation model in order to bridge the gap between physical and digital. In physical phenomenon, during cabin cooldown, after meeting the set/ target cooling of a cabin, the ACC takes place. During ACC, gradual heat transfer takes place between cold evaporator surface and air flowing over it because of evaporator thermal inertia.

Polymers are substituting traditional materials, such as metals, in existing as well as new applications, both for structural and aesthetic applications as they are lightweight, customizable and are easy to mould into complex shapes. With such an extensive use of polymers, there is a need to carefully scrutinize their performance to ensure reliability. This is particularly the case in the automotive and electronic industries where the aesthetic appeal of their products is of prime concern and any visible scratch damage is undesirable. Concern for aesthetics has led to a need for the quantification of visibility due to scratch damage on polymeric surfaces Many painted plastic parts used in vehicles are being replaced with the molded-in color plastics for cost reduction and also due to environmental concerns associated with solvent emissions. There are multiple methods used for scratch evaluation of polymers and paints.

The future of bus transit in new millennium is promising. This optimism is based on an anticipated long-term slowdown in growth of suburbs and revitalization of central cities. It reflects and escalates the public concern with traffic congestion, sprawl and pollution. This calls for double the use of public transport to address above issues. It calls for changing the mind-set of society towards public transports like buses, coaches etc. This could happen if bus design ensures right comfort, safety and TCO by ensuring refined bus transport. Hence, it is responsibility of OEMs to provide the new generation buses and coaches, which will ensure the public demands of comforts in terms of NVH refinement. This paper covers the unique approach used to convert the existing bus NVH refinement to next level as a short-term solution and with the intention of articulating NVH strategies for new generation bus development.

Tailgate stoppers play vital role in exerting preload on the Tailgate latch mechanism and also restrict the relative motion of the Tailgate against vehicle Body in White (BIW). These stoppers act as over-slam dampeners and reduce the transmissibility of vibrations thereby reduce the risk of Squeaks & Rattles (S&R) noises. S&R noises from Tailgate are most annoying to the rear passengers in the vehicle and are recurring in nature. Preventing these issues during design is a challenging task. S&R risk simulations enable us to conduct virtual Design of Experiments (DOEs) and arrive at optimal solutions. This approach helps in reducing the cost of the design changes that are required in the physical prototype at the later stages of product development and save time. The risk evaluation in the simulations is based on the relative displacement at the interfaces of two components.

In recent years, there has been a rapid growing demand for laser brazing in the transportation industry for automotive-Body in White (BIW), steel sheet assembly. Implementation of laser brazing is aimed primarily to improve productivity, quality of joints and cost. Laser brazing works by filling the opening amongst two substrates by melting the filler wire with the help of laser beam (used as a heat source), whereas in conventional resistance spot welding, contacting metal surface points are joined by the heat obtained from resistance to electric current. BIW is essentially a welded metal structure which is meant to provide durability and crashworthiness to the vehicle and is conventionally assembled using resistance spot welding process. The BIW structure comprises of various steel grades having varying thicknesses, compositions, microstructures and mechanical properties.

The Common Rail fuel injection System (CRS) has completely changed the whole diesel engine combustion cloud dynamics and enhanced the applicability of diesel engines further with a motto of providing a more cleaner sky and greener earth. The most cutting-edge technological developments made in CRS and EGT system enables OEMs to achieve further more stringent emission norms and adopt the environmental protection compliances. Today’s CRS systems are the most advanced generation fuel injection systems providing further high injection pressures, wide multiple injections capability with shorter dwell periods enabling real smoother Digital Rate Shaping (DRS) and injection control that benefits not only the engine combustion performance but also enables smarter thermal management of modern exhaust systems while meeting stringent emission compliances and achieving future CO2 reductions goal.

The goal of reducing fuel consumption and CO2-Emission is leading to turbo-charged combustion engines that deliver high torque at low speeds (down speeding). To meet NVH requirements damper technologies such as DMF (Dual Mass Flywheel) are established, leading to reduced space for the clutch system. Specific measures need to be considered if switching over from SMF (Single Mass Flywheel) to DMF [8]. Doing so has an impact on thermal behavior of the clutch system, for example due to reduced and different distribution of thermal masses and heat transfer to the surroundings. Taking these trends into account, clutch systems within vehicle powertrains are facing challenges to meet requirements e.g. clutch life, cost targets and space limitation. The clutch development process must also ensure delivery of a clutch system that meets requirements taking boundary conditions such as load cycles and driver behavior into account.

The public transport in India is gradually shifting towards electric mobility. Long range in electric mobility can be served with High Voltage Battery (HVB), but HVB can sustain for its designed life if it’s maintained within a specific operating temperature range. Appropriate battery thermal management through Battery Cooling System (BCS) is critical for vehicle range and battery durability This work focus on two aspects, BCS sizing and its coolant flow optimization in Electric bus. BCS modelling was done in 1D CAE software. The objective is to develop a model of BCS in virtual environment to replicate the physical testing. Electric bus contain numerous battery packs and a complex piping in its cooling system. BCS sizing simulation was performed to keep the battery packs in operating temperature range.