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In a current competitive automotive market, weight and cost optimization is the need of an hour. Therefore it is important to explore use of alternative material which has less weight, low manufacturing cost and better strength. This paper presents methodology to achieve cost & weight reduction through use of Austempered Ductile Iron (ADI) instead of alloy forging. ADI casting has lower density, physical properties at par with alloy forgings and lower manufacturing cost. Pivot arm is the one of the critical component of twin axle steering system which transfers the hydraulic torque from steering gearbox to second forward axle via linkage system. In order to design lightweight pivot arm, existing chromium alloy steel material is replaced with the Austempered ductile iron (ADI). Pivot arm is designed and validated digitally as well as bench test and results are found to be meeting cost and weight targets.

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.

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 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.

Design of HVAC system plays an important role in acoustic comfort for passengers. With automotive world moving towards electrical vehicles where powertrain noise is low, designing low noise HVAC system is becoming more important. For an automobile manufacturer, ability to predict the production vehicle cabin noise at the early design stage is important as it allows more freedom for design changes, which can be incorporated in the vehicle at lower cost. Although HVAC prototype and system level testing at early design stage is possible for noise estimation but flow field is not visible in test that makes difficult to improve design. CFD simulation can provide detailed information on flow field, noise source strength and location. But in such a simulation, accurate prediction has been a challenge due to the inability of CFD tools to model acoustic absorptive characteristics of interior walls of cabin.

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.

The changing mobility landscape of India reveals that the erstwhile transport modes of the 20th century i.e., railways and road buses are making way for airlines, personal vehicles, shared mobility, metro rails. Rapid technological changes, stricter regulations, new transport cultures autonomous, connected, electric and shared (ACES), state-of-the-art and environmental concerns are shaping up the eco-system for automobiles. Despite these challenges roadways and automobiles will continue to be most prominent solution in India for future. But for that, the automobile sector should be agile, innovative, and adaptable to changing eco-system, vigilant to thwart threat of alternate mobility solutions and must provide sustainable solutions for the future. The purpose of this paper to evaluate various mobility solutions, ascertain prominence of upcoming automobile solutions and their sustainability for future in India.

Currently, automotive industries are using Advanced High-Strength Steels (AHSS) sheet grades to achieve key requirements like light weighting and improved crash performance. But forming of AHSS grades becomes key challenge due to its lesser ductility and edge fracturing tendency during forming. In general, most of the automotive components undergoes shearing operations like blanking and punching which affects the edge ductility of the steel. AHSS grades possess limited edge ductility compared with conventional steel grades which results in edge fracturing due to tensile strain during stretch flanging operation. Stretch flange-ability is an important formability characteristic, which aids in material selection to avoid edge fracturing of complex shaped parts. Material with better stretch flange-ability possess better edge ductility and hence perform better in stretch flanging of sheet metal.

Vehicles subjected to Indian duty cycles have to undergo extreme environments & road terrains, stone chipping. Underbody wear from this is one of the most significant forms of deleterious corrosion. Automobile companies deal with this by going for exotic & expensive underbody coating, which compositionally are "Polyvinyl Plastisol also popularly known as Poly Vinyl Chloride (PVC)". Across automotive industry, the stone chipping is prevented via applying PVC-coating to the extent of 800-1000 microns. The application of PVC-material throughout the vehicle underbody will add approximately 8-12 Kgs of weight. Our objective was to reduce the weight of applied PVC-material.

In this present investigation an attempt has been made to simulate the refrigerant flow through pipes using Computational Fluid Dynamics (CFD) to observe liquid refrigerant R134a flashing phenomenon using multi-phase model in ANSYS Fluent. In a vehicle HVAC piping system the refrigerant flows under a certain operating condition and pipe packaging. When the vehicle is kept in idle condition there is a possibility that a local pressure drop may occur due to change in pipe configuration or change in operating conditions. This leads to phase change and it can be one of the factor which causes noise and vibrations in the refrigerant pipe. The unwanted noise created due to refrigerant fluid phase change inside HVAC pipe can be annoying to end user. Prediction of refrigerant flow noise through HVAC pipes is more challenging and a time consuming process.

IC Engine manufacturers are constantly in pursuit of better sealability of cylinder head and engine block interface for meeting performance and durability targets. In order to overcome variation in torque - tension characteristics of cylinder head bolt because of friction variations, yield based clamping are being extensively adopted. Current study is done on torque - tension characteristics of a cylinder head bolt with a controlled quality. The paper enumerates the experimental setup representing a sub 1 liter all aluminum engine's head-block joinery. Studies on torque - tension characteristics of cylinder head bolt and the effect of sealing interface using a cost effective single layer steel gasket are being discussed in the paper. Subject work has led to a successful implementation of angular torque parameters on head bolts to meet functional and durability targets.

Brake system is the most important system in the vehicle considering the overall vehicle safety and speed control. Brake applications are repetitive during a city traffic and hilly terrain on downhill gradient. Frequent braking gives rise to an overheating of the brake drum and its components. Braking operations at high temperature gives rise to problems like reduced deceleration due to loss of brake pad friction characteristics, pad softening and sticking to drum, pad distortion and wear etc. All these factors collectively result in deterioration of the braking performance and reduction of brake pad durability with time. Till date most of the thermal analysis performed for brake drum heating are through physical testing using brake system prototypes and by means of CFD tools. These methods are time consuming and expensive. There is a need for an alternative method to reduce physical trials and prototype building and reduce dependency on CFD analysis.

An automotive radiator cooling fan has been observed to be an important noise source in a vehicle and with increasing noise refinements, the need for a quieter but effective fan is of utmost importance. Although some empirical prediction techniques are present in literature, they are not sufficiently accurate and cannot give a detailed view of the entire noise spectrum and the various noise prone zones. Hence the need for highly accurate Computational Fluid Dynamics (CFD) study is essential to be able to resolve the minute acoustic stress. Large Eddy Simulation technique in CFD is used to resolve the minute scales of motion in the flow as the sound pressures simulated are very small compared to system level pressures and require immense accuracy. Detailed mesh dependency and Y+ studies are conducted to implement higher accuracy as well as keep mesh requirements within computationally feasible zone.

In today’s competitive scenario, the automotive product life cycle has drastically reduced and all Auto OEM’s are coming up with their updated products with lesser development time. These frequent product upgrades are possible due to use of various digital tools during product design and development. Design and optimization of engine coolpack (powertrain cooling unit) to attain engine cooling performance is one of the important parameter during vehicle development or upgrade. Hence, to keep control over development cost and time of delivery, quick and accurate digital validation capability like one dimensional (1D) simulation is the need of the hour. To predict the powertrain cooling (PTC) performance at vehicle concept stage, when physical prototypes are not available, airflow data from similar developed platforms is considered as an input for 1D simulation.

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.

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 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.

In the recent years, Hybrid and Electric Vehicles (EVs) have gained attention globally due to conventional non-renewable fuels becoming expensive and increasing pollution levels in the environment. Li-ion battery EV’s are most popular because of their better power density, spe. energy density and thermal stability. With the advent of battery EV’s, concerns regarding thermal safety of vehicle and its occupants has grown among the prospective customers. Temperature plays an important role in the performance of the Li-ion battery which includes cell capacity, charge output, vehicle range, mechanical life of the battery etc. For Li-ion cells, optimum operating range should be between 15-35 °C [1], and all cells must also be maintained within a ±5 °C variation band. Computational Fluid Dynamics (CFD) simulation can be used to get better insight of cell temperature inside battery. But CFD simulation process is complex, time consuming involving multi-physics and exhaustive computations.

The main task of the automotive headlights on cars is to illuminate the roadway and facilitate the driver fatigue-free and safe driving. An automotive headlamp is exposed to thermal variations during its operations and also exposed to the different environmental conditions. Automotive headlamp compartment is not completely sealed and vents are provided to exchange the air between environment and headlamp compartment for thermal cooling of the internal components. An automotive headlamp compartment is an environment with high thermal and low air flow exchanges with the ambient as results humidity can accumulated inside the headlamp compartment and there is a possibility of thin mist layer formation on the lens inner surface [1]. The combined use of numerical simulation and experimental studies is an important approach for headlamp design. This paper summarizes CFD simulation results for automotive headlamp condensation and de-condensation using ANSYS FLUENT.

In current scenario, there is trend to use stainless steels in place of carbon steels and aluminized carbon steels for Exhaust application. In response to changing regulatory requirements and durability performance requirements of exhaust systems, the ferritic stainless steels are proven to be best suited for the purpose. There are multiple ferritic stainless steels available as options for exhaust system. The material in an exhaust system is subject to heat, oxidation, corrosion and condensate. These environment condition demands that exhaust material should possess high temperature corrosion and oxidation resistance along with required mechanical performance such as vibration and thermo-mechanical load cycles. This work is an attempt to develop simulated test methods for corrosion and thermal environment and evaluate performance of commonly used ferritic stainless steels.