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Automotive OEMs quest for vehicle body light weighting, increase in Fuel efficiency along with significant cut in the emissions pose significant challenges. Apart from the effect on vehicle handling, the reduction of vehicle weight also results in additional general requirements for acoustic measures as it is an important aspect that contributes to the comfort and the sound quality image of the vehicle, thus posing a unique challenge to body designers and NVH experts. Due to these conflicting objectives, accurate identification along with knowledge of the transfer paths of vibrations and noise in the vehicle is needed to facilitate measures for booming noise dampening and vehicle structure vibration amplitude. This paper focuses on the application of a unique design and development of vehicle body structure anti-vibration dynamic damper (DD), unique in its aspect in controlling booming noise generated at a specific RPM range.

Hydromount plays an important role in isolating vibration during idling. To meet ideal NVH criteria, a properly tuned Hydromount is required otherwise there will be abnormal noise due to cavitation effect. Cavitation noise is such a noise which is very difficult to identify in initial vehicle development stage. The effects of cavitation in the Hydromount become increasingly important for noise and performance goals. Cavitation is the formation and collapse of vapor bubbles in a working fluid when local static pressure falls below the vapor pressure of the working fluid. Technique to detect cavitation in Hydromount is presented in this paper. The countermeasure technique concentrates on increasing the fluid flow rate betweens fluid chambers. The results for different design countermeasure performance have been measured and the performance is compared in the vehicle. The results of vehicle level tests show the same trends as bench test results.

In a highly competitive market, one of the major challenges for an automobile designer is to lower the product cost while improving the performance. Therefore, from the vehicle comfort point of view, achieving a good ride, handling and NVH performance, while satisfying the low cost and low weight target needs attention from the concept stage of the development cycle. To achieve this balance, it is important to optimize the static and dynamic stiffness of the vehicle body. This paper focuses on the effect of vehicle body stiffness on the ride, handling and NVH parameters. It also addresses the relation between static and dynamic stiffness of the vehicle. The correlation of the stiffness values with the ride, handling and NVH performance is also studied through various experiments on the actual vehicle

With the advancement of regulatory norms in automobile industry, there is a challenge to meet performance efficiency targets, especially with a lightweight platform, while providing superior driving experience to customers. The shift towards weight optimization, makes the vehicle structure more susceptible to transfer a diverse range of noise and vibrations through body. Although most undesirable noises perceived inside the cabin can be reduced by superior technology engine mounts and NVH packaging, all such solutions lead to cost addition. Intelligent considerations in part design can be used to supplement predictable transfer paths to quell the unwanted vibrations. One such case is of the gear whine noise in certain rpm bands caused by inherent gear meshing frequency coinciding with natural frequency of an engine mounting bracket.

The Indian passenger vehicle market has grown by more than 40% by volume in the last decade and has reached a record high in FY23. This has created a more diverse and demanding customer base that values interior design and quality. The modern customer expects a high level of aesthetics and sophistication in their vehicle interiors - including in the luggage area. The Luggage Cover (Parcel Tray) is a component in the luggage area of a passenger vehicle that is used to conceal the luggage & improve its aesthetics. The cover is generally made of thermoplastic material with rotating hinges and is held in its place by the compression from the back door, which is frequently opened and closed. The parts that connect the cover to the door (usually an elastomer interface on the thermoplastic tray) tend to change over a period due to climatic conditions and leads to rattling concerns over a period.

The aim of the research was to explore and establish aspects that affect ageing of non-woven fabrics used in automobiles. One of the most vulnerable parts in a vehicle, at the behest of the customer, is the Floor Carpet. Original Equipment manufacturers are continually binging at doable options for providing low cost carpets that are functionally and aesthetically durable throughout the vehicle life. [1] Car interiors, especially carpet, must remain in impeccable condition to uphold a good resale value. Targeting the analysis of causes that affect ageing of non-woven fabric material will form the core study of the literature to follow. The establishment of which shall ascertain some viable solutions to augment quality of the contemporary non-woven automotive carpet.

Powertrain Control development has gone through many changes in terms of process, tools and practice at all OEM's across the geography. This is mainly driven by increased number of powertrain components for control, shorter development schedules, cost control, and the need to realize the potential of electronic control to increase the performance, efficiency, safety and comfort. With the significant advancement in Powertrain Controls and additions of electronic functions, it has become imperative to automate the controller development process in the V-cycle to reduce the time and make the process more efficient while detecting any logic failures upfront at the early stage of the development cycle. Traditional practices and tools of defining the controls cannot meet new requirements. Model Based Design (MBD) approach is a promising solution to meet the critical needs of powertrain control engineering to define the control logic and validate.

As automobile design has become more sophisticated, the level of noise inside the vehicle has been dramatically reduced. The sources of noise which were previously ignored have now become relatively more significant, and it has become desirable to reduce the noise from such sources. The noise from the fuel system may be low but the fact that it operates continuously whether or not vehicle is moving, makes its noise level more noticeable. So in order to achieve overall better NVH characteristics in a car it is important to minimize the noises from fuel delivery system. The current paper addresses the fuel pulsation noise from fuel delivery line and describes countermeasure approach for noise reduction using an Experiment Based Design approach (EBD).

Exhaust system of an automobile is primarily employed in automobile to purify exhaust gases and reduce noise due to combustion. However, a side-effect of the above function is the increase in backpressure. As specified in various literatures, an increase in backpressure can lead to a deterioration on engine performance (Power & torque). Benefit of backpressure reduction can be further taken in terms improving the power & torque of engine or improving the fuel economy. With growing concerns related to global warming and CO2 emissions, reducing exhaust back pressure is one of the promising areas in engine design in order to improve the fuel economy of the automobile and achieving carbon neutrality targets. However, reducing the back pressure generally tends to deteriorate the noise attenuation performance of the Exhaust system.

The automobile market is witnessing a different trend altogether - the trend of shifting preference from powerful to fuel efficient machines. Certain factors like growing prices of fuel, struggling global economy, environmental sensitiveness and affordability have pushed the focus on smaller, efficient and cleaner automobiles. To meet such requirements, the automobile manufacturers, are going stringent on vehicle weights. Using electric and hybrid power-plants are other options to meet higher fuel efficiency and emission requirements but significant cost of these technologies have kept their growth restricted to only few makers and to only few regions of the globe. Optimizing the vehicle weight is a more attractive option for makers as it promises lesser time to market, is low on investment and allows use of existing platforms.

Engine noise is a major source of noise inside the vehicle compartment. Recently, the quietness of the occupant cabin has become an important dimension to the quality of product. OEMs are finding it challenging to meet the customer expectations for “Powerful yet quiet” attribute. Several focused studies have been made to reduce the under hood component noise in automobiles. This paper summarizes the optimization of the vibro-acoustic sensitivity (VAS) of the engine mounts of a small car engine. The contribution of each engine mount on the structure-borne noise transfer inside the cabin is the prime focus of this study. In the current analysis, the body side and engine side mounting bracket stiffness analyses are carried out to reduce the vibro-acoustic transfer. Experimental methods like conventional FRF, on-road data acquisition and physical prototyping have been used.