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This paper discusses the test setup and methodology required to validate complete lift axle assembly for simulating the real time test track data. The correlation of rig vs track is discussed. The approach for reduction of validation time by eliminating few of the non-damaging tracks/events, its correlation with real life condition is discussed, and details are presented. With increased competition, vehicle development time has reduced drastically in recent past. Bench test procedure using accelerated test cycle discussed in this paper will help to reduce development time and cost. Process briefed in this paper can also be used for similar test specification for other structural parts or complete suspension system of heavy commercial vehicles.

The automotive sector is going through a phase of stiff competition among various Original Equipment Manufacturers for increasing their profitability while ensuring highest levels of customer satisfaction. The biggest challenge for such companies lies in minimizing their overall cost involving investments in Research and Development, manufacturing, after sales service and warranty costs. Higher warranty costs not only affect the net profit but in turn it also affects the brand image of the company to a large extent in the long run. An effort is made here to target such warranty costs due to frequent tail pinion and hub seal leakages on single reduction/hub reduction axles of Heavy Commercial Vehicles in the field. A preliminary study involving the severity analysis of such failures is followed by a step by step investigation of these failures.

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.

Transportation has significant and long-lasting economic, social and environmental impacts which makes it an important dimension of urban sustainability. The World is witnessing rapid changes in modern traveling behavior, and efforts are continuously being made to stimulate sustainable mobility solutions with smart policies, new business models, and advanced technologies (connected cars, sensors, electrification). However, the shift is gradual in India when compared to developed countries due to unique barriers to emerging green mobility solutions. This paper empirically investigates public travel satisfaction and the primary factors for the selection of modes for different types of commutes. Quantitative data were collected including socio-demographic, travel mode choices, and preferred future mobility solutions from the western states of India.

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 commercial vehicle market in India is shifting to higher payload capacity vehicles due to a lower transportation cost per unit goods. To cater this requirement, the vehicle manufacturers are designing the heavy multi-axle commercial vehicles and with higher per axle loading capacity. One of such a vehicle design involves five-axle vehicle with non-steerable, twin tire, lift axle. Though using a twin tires have increased loading capacity of lift axle compared to a single tire self-steerable lift axle, it can cause tire scrub while vehicle is turning and leads to a significant tire wear. The tire wear possibility due to use of non-steerable lift axle is estimated through simulation using full vehicle model in ADAMS. The operating zone of the vehicle, where maximum tire wear can occur, is identified through simulation. Different alternatives to reduce tire wear for this scenario are also discussed.

The Indian automotive industry has taken a big leap towards stringent Bharat Stage VI (BS VI) emission standards by year 2020. A digital driven design and development focusing on innovative and commercially viable technologies for combustion and exhaust after-treatment system is the need of the time. One-dimensional (1D) simulation serves as a best alternative to its counterparts in terms of obtaining faster and accurate results, which makes it an ideal tool for carrying out optimization studies at system level. In this work, 1D chemical kinetics modelling and analysis of exhaust after-treatment system (EAT) for a heavy-duty diesel has been performed using GT-Power. Initially, a single site 1D model for a diesel oxidation catalyst (DOC) has been developed and then, a two-site, 1D model for a selective catalytic reduction (SCR) catalyst was also developed based on reactor data.

HVAC system design has an accountability towards acoustic comfort of passengers of a vehicle. Owing to larger cabin volume of a bus, multiple air blowers have to be installed to ensure comfort of passengers. Such multiple blowers produce significant flow induced noise inside the cabin. For commercial success, it becomes essential to predict intensity of such a flow induced noise at very early stages in product development. Conventionally sliding mesh based CFD approach is deployed to predict flow and turbulence noise around each blower. However due to complexity, this method becomes computationally intensive resulting in cost and time inefficiency. Hence it is desirable to innovate around an alternative rapid, reliable prediction method, which ensures quick turnaround of prediction.

Modern day diesel engines use systems like Exhaust Gas Recirculation (EGR), Variable Geometric Turbo Charger (VGT), inlet throttle for air regulation, multiple injection strategies, high pressure rail systems for fuel regulation to optimize the combustion for meeting the strict emission and fuel consumption demands. Torque based ECU structures which are commonly used for diesel engines require a large amount of calibration work. Conventional manual methods for emission and fuel consumption optimization (Full factorial or Line search method) results in increased test bed usage and it is almost impossible to use these methods as the number of parameters to optimize are very high. The conventional DoE tests have been limited by the necessity of calibration engineer’s expertise and manual prescreening of test points to be within thermal & mechanical limits of engine systems. This subsequently leads to excessive screening of variables; which is time consuming.

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.