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Till recently supercharging was the most accepted technique for boost solution in gasoline engines. Recent advents in turbochargers introduced turbocharging technology into gasoline engines. Turbocharging of gasoline engines has helped in powertrains with higher power density and less overall weight. Along with the advantages in performance, new challenges arise, both in terms of thermal management as well as overall acoustic performance of powertrains. The study focuses mainly on NVH aspects of turbocharging of gasoline engines. Compressor surge is a most common phenomenon in turbochargers. As the operating point on the compressor map moves closer to the surge line, the compressor starts to generate noise. The amplitude and frequency of the noise depends on the proximity of the operating point to the surge line. The severity of noise can be reduced by selecting a turbocharger with enough compressor surge margin.

Nowadays, perception of automotive quality plays a crucial role in customer decision of vehicle purchase. Hence, automotive OEM’s are now working on the philosophy of “Quality Sound”. Out of all the Noise, Vibration & Harshness (NVH) issues identified in a vehicle, the ranking of Buzz, Squeak & Rattle (BSR) stands high and glove box rattle is one of the issues that is continuously observed in all customer verbatim. Specific issues like lid rattle and latch rattle are predominant and gets worse over mileage accumulation. Also minimizing BSR issues in glove box is difficult due to complex latch mechanism. While deciding the bump stop specifications more weightage is given to efforts. The bump stop is selected in a way as not to increase the glove box opening and closing efforts, but the selected bump stops will not provide enough preload to glove box lid leading to rattle issues.

The cabin cool down performance is influenced by heat load, AC system components and Air handling components. The air handling components are AC duct, vane and vent. Design of AC duct vane plays a crucial role in the airflow directivity in cabin which enhances the cabin cool down performance. Simulations are carried out by rotating the vanes manually and requires post process for every iteration. It leads to more time consuming and more number of simulations to achieve the target value. Research articles focusing on automation and optimization of vane articulation studies are scanty. Thus, the objective of this work is to execute the vane articulation study with less manual intervention. A parametric approach is developed by integrating ANSA and ANSYS FLUENT tools. With Direct Fit Morphing and DoE study approach from ANSA delivers the surface mesh model for the different vane angle configurations.

Squeak and rattle concerns account for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are a major quality concern for automotive OEM’s. Seat is one of the major contributors of squeak and rattle issues observed in customer verbatim. Seat head rest rod and bezel are designed concentric to each other with a gap that allows free movement and a locking pin to position at different levels. Due to the design gap and weight of the head rest there is always tendency for relative displacement leading to rattle issues. Seat headrest, is close to the customer ear and any rattles at headrest will create annoying driving experience. Also, the contradictory requirements between efforts and rattle makes the scenario more difficult to fine tune the bezel specifications. The root cause for head rest rattle issues can also be related to free play between bezel and seat frame, free play between bezel and cap, looseness between locking pin and headrest rod etc.

Dual mass flywheel (DMF) is an excellent solution to improve the noise, vibration, and harshness (NVH) characteristic of any vehicle by isolating the driveline from the engine torsional vibrations. For the same reason, DMF’s are widely used in high power-density diesel and gasoline engines. However, the real-world usage conditions pose a lot of challenges to the robustness of the DMF. In the present work, by capturing the Real-World Usage Profile (RWUP) conditions, a new methodology is developed to evaluate the robustness of a DMF fitted in a Sports utility vehicle (SUV). Ventilation holes are provided on clutch housing to improve convective heat transfer. Improvement in convective heat transfer will increase the life and will reduce clutch burning concerns. Cities like Mumbai, Chennai, Bangalore, roads will have clogged waters during rainy season. When the vehicle was driven in such roads, water enters inside the clutch housing through ventilation holes.

The Indian automotive industry has migrated from BS IV (Bharat stage IV) to BS VI (Bharat Stage VI) emission norms from 1st April 2020. This two-step migration of the emission regulations from BS IV to BS VI demands significant engineering efforts to design and integrate highly complex exhaust after-treatment system (EATS). In the present work, the methodology used to evaluate the EATS of a high power-density 1.5-liter diesel engine is discussed in detail. The EATS assembly of the engine consists of a diesel oxidation catalyst (DOC), a diesel particulate filter with selective catalytic reduction coating (sDPF), urea dosing module and urea mixer. Typically, all these components that are needed for emission control are integrated into a single canning of shell thickness ~1.5mm. Moreover, the complete EATS is directly mounted onto the engine with suitable mounting brackets on the cylinder block and cylinder head.

The main function of an air conditioning system in a vehicle is to provide the thermal comfort to the occupant at minimum possible energy consumption in all environmental conditions. To ensure the best possible thermal comfort, air conditioning system is optimized on various parameters like heat load, air flow distribution, glass area, trim quality, insulations and cabin leak rate. A minimum cabin leakage is regulatory requirements to ensure the air quality of cabin. Anything above the minimum cabin leak rate ultimately turn into reduced thermal comfort and additional energy consumption. The additional energy consumption to maintain the required thermal comfort in the cabin due to cabin leakage affects the fuel efficiency severely. In the present study, the effect of cabin leakage on fuel efficiency and thermal comfort is studied in details by varying the cabin leakage through mechanical means. The experiments are carried out in normal environmental condition and road condition.

From International Energy Statistics (IES) survey, China, US and India are top three countries in emitting CO2 emissions. Further, worldwide national governments are focused to control CO2 emissions at source by stringent regulatory limits. OEMs and Research laboratories are working on several technology options such as advanced fuel injection system, optimizing in cylinder combustion system, thermal management and reduced engine friction to meet this legal requirements. In this paper, research work focused on improving combustion system through selection optimum bowl geometry and increasing volumetric efficiency through valve timings, profile and intake system using both 1D and 3D-CFD numerical approach. The main objective of this approach to utilize fossil fuel to its maximum potential in a single cylinder Naturally Aspirated (NA) water cooled engine with CRDI.

Light weighting is the Current trends in automotive to achieve better fuel economy which helps for meeting fuel economy standards & to offset the higher fuel prices. Thus there is a need to develop composite running board which is light weight & structurally sound enough to meet the performance. The present paper provides a composite running board assembly for an automobile. The running board assembly includes a board, an insert body and a plurality of brackets. Upon stepping of a passenger on the board, the board transfers load on the insert body which subsequently transfers the load to the plurality of brackets thus facilitating even distribution of the load on the automobile body. This paper also put lights on the use of improved TRIZ application - an approach to inventive problem solving for designing highly affordable & light weight running board. The cost & weight reduction achieved with innovative design is about 40 % & 35 % comparing to existing cost & weight.

Brake groan noise is resolved without any major change in the design of brake system and vehicle sub-system components in the development phase of a utility vehicle. The groan noise is observed during the end of the stopping of the vehicle under moderate braking. The concerned NVH issue is perceived as unacceptable noise in the passenger compartment. Groan induced vibration is subjectively felt on steering and seat frame. A typical process is established to successfully reproduce the groan which helped in precisely evaluating the effect of modifications proposed. The temperature range of the disc which has the highest probability to produce the groan noise is found out experimentally. The transfer path analysis is carried out to find the path contributions from suspension. Acoustic transfer functions from considered paths are measured with the suspension removed from vehicle.

Transportation system is at the brink of revolution and many new ways of mobility are arising in the market to ease the pressure on the established transportation infrastructure. Many companies and governments around the world are exploring innovative options in the space of shared mobility to reduce the overall carbon footprint. To expedite the adoption of shared mobility in India, it is necessary to make such options comfortable and cost-effective. One of the most effective way to make shared mobility options cost effective is to comfortably increase occupancy per vehicle footprint. This paper aims to evaluate a novel method of occupant seating to identify the maximum number of passengers a vehicle can accommodate without significant impact on occupant comfort. It is assumed that shared mobility options are used for a short duration of commute, and hence the comfort of the seat can be marginally compromised to increase the total number of occupants.

Among many environments, the motor vehicle cabin micro-environment has been of public concern. Infact Air pollution more harmful to children in cars than outside. Although commuters typically spend only 1-2hrs per day of their time in vehicles, the emissions from various interior components of motor vehicles as well as emissions from exhaust fumes carried by ventilation supply air are significant sources of harmful air pollutants that could lead to unhealthy human exposure due to their high concentrations inside vehicles’ cabins. This N9 silver ion technology helps significant reduction of microbial & viruses inside the vehicle cabin air. On contact silver will neutralize harmful bacteria on plastic surfaces giving them long lasting freshness and long-term protection. Silver is a natural antimicrobial. That means that microbes-germs can’t survive in the presence of silver ions. Silver ions released from the surface of silver molecules.

Reducing material wherever there is a possibility in automobile industry is inevitable for weight and cost saving. This paper explains about the possibilities of optimizing the material composition of automotive Headliners (also called as Roof liners) without affecting the performance and safety criteria. In this paper, we are targeting at optimizing the individual constituents of a composite Headliner. A conventional Headliner comprises of many sandwich layers of which PU foam shares the major percentage of the composition contributing to 80% of the Headliner thickness. In this paper, we are discussing about the optimization done in Headliner sandwich constituents without affecting the core performance parameters of headliner such as curtain airbag deployment, ergonomic regulations, drop test etc. By incorporating this change, without significant changes in other layers, overall weight reduction of ~24% and overall cost reduction of ~24% is achieved.

Selection of EGR system is very complex for a particular engine application. The performance of the EGR system depends highly on the Cooler Heat Transfer Efficiency. Cooler effectiveness drops over a period of operation due to soot deposition, HC condensation, and fuel quality. This phenomenon is called as Cooler Fouling. Fouling cannot be avoided completely but the level of performance drop over time has to be studied and minimized. The minimum pressure drop and the highest efficiency in fouled condition is the target for selection of a cooler. In this study, various parameter combinations like tube shape and profile, tube length, number of tubes, tube diameter, and pitch of corrugations, which influence the cooler performance were tested. A better understanding of each of its effect on cooler effectiveness and fouling behavior was obtained. The tube shape was changed from rectangular to circular, also from smooth surface to corrugate.

During the vehicle launch (i.e. moving the vehicle from “0” speed), the clutch would be slowly engaged by the Driver or Transmission Control Unit (in Automatic Transmission/Automatic Manual Transmission vehicle) for smooth torque transfer between engine and transmission. The clutch is designed to transfer max engine torque with min heat generation. During the clutch engagement, the difference in flywheel and gearbox input shaft speed is called the clutch slipping phase which then leads to a huge amount of energy being dissipated in terms heat due to friction. As a result, clutch surface temperature increases consistently, when the surface temperature crosses the threshold limit, the clutch wears out quickly or burns spontaneously. Hence it is crucial to predict the energy dissipation and temperature variation in various components of clutch assembly through virtual simulation.

This paper discusses design and optimization process for the integration of exhaust manifold with turbocharger for a 3 cylinder diesel engine, simulation activities (CAE and CFD), and validation of manifold while upgrading to meet current BS6 emissions. Exhaust after-treatment system needs to be upgraded from a simple DOC (Diesel Oxidation Catalyst) to a complex DOC+sDPF (Selective catalytic reduction coated on Diesel Particulate Filter) to meet the BS6 emission norms for this engine. To avoid thermal losses and achieve a faster light-off temperature in the catalyst, the exhaust after-treatment (EATS) system needs to be placed close to the engine - exactly at the outlet of the turbocharger. This has given to challenges in packaging the EATS. The turbocharger in case of BS4 is placed near the 2nd cylinder of the engine, but this position will not allow placing the BS6 EATS.

Nowadays, tractors are frequently used with front-end loaders, dozers and backhoes to cater to various non-agricultural and construction application needs. These applications require frequent shifting of gears due to the constant need for a tractor's forward/reverse direction of motion. Hence, the tractors are fitted with a power shuttle transmission (PST) to cater this need. Power-shuttle transmission (PST) development is a design process that incorporates multiple disciplines such as mechanical, hydraulics, controls and electronics. This paper presents a simulation-based approach to model the power shuttle transmission of the tractor. Firstly, individual components of PST are modelled in detail and then integrated with the complete tractor model. For this, GT-Suite has been used as a simulation platform.

For effective occupant protection, automotive vehicle structure needs to be developed for seat anchorage test to prevent the failure of seat anchorages during high speed impacts. Seat anchorages (SA) certification test is mandatory for M & N category vehicles in India. Conventional way of testing automotive vehicle structures for seat anchorage test is using deceleration sled with the help of bungee ropes. Deceleration pulse generated from the physical test is used as a loading input in the current CAE process. With the current CAE method, final deformation of the vehicle structure looks similar to physical test, however, the vehicle visual interactions differ significantly during the deformation event. In the current study, a modified loading methodology is proposed to match both the final deformation as well as vehicle visual interactions. Loading and boundary conditions of physical test were understood in detail with the help of simple free body diagrams.

Overall in-vehicle visibility is considered as a key safety parameter essentially mandated due to the increasing traffic scenario as seen in developing countries. Driver side bottom corner visibility is one such parameter primarily defined by A-pillar bottom and outside rear-view mirror (OSRVM). While defining the OSRVM package requirements such as size, position and regulatory aspects, it is also vital to consider other influencing parameters such as position of pillars, waist-line height, and Instrument panel which affect the in-vehicle visibility. This study explains the various package considerations, methods to optimize OSRVM position, shape and housing design in order to maximize the in-vehicle visibility considering the road and traffic conditions. A detailed study on in-vehicle visibility impacted by OSRVM packaging explained and had been verified for the results.

During the cold start conditions engine must overcome higher friction loss, at the cost of fuel penalty till the optimum temperatures are reached in coolant and lubrication circuits. The lower thermal capacity of the lubrication oil (with respect to the coolant) inverses the relation of viscosity with temperature, improves engine thermal efficiency benefit. Engine oil takes full NEDC test cycle duration to reach 90°C. This leads to higher friction loss throughout the test cycle, contributing a significant increase in fuel consumption. Increasing oil temperature reduces viscosity, thereby reducing the engine friction. This helps to identify the focus for thermal management in the direction of speeding up the temperature rise during a cold engine starting. This work aims at the study and experiment of an exhaust recovery mechanism to improve the NEDC fuel economy.