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In-cabin Noise at low frequency (due to engine or road excitation) is a major issue for NVH engineers. Usually, noise transfer function (NTF) analysis is carried out, due to absence of accurate actual loads for sound pressure level (SPL) analysis. But NTF analysis comes with the challenge of having too many paths (~20 trimmed body attachment locations: engine and suspension mounts, along with 3 directions for each) to work on, which is cumbersome. Physical test transfer path analysis (TPA) is a process of root cause analysis, by which critical contributing paths can be obtained for a problem peak frequency. In addition to that, loads at the attachment points of trimmed body of test vehicle can be derived. Both these outputs are conventionally used in CAE analysis to work on either NTF or SPL. The drawback of this conventional approach is that the critical bands and paths suggested are based on the problem peak frequency of test vehicle which may be different in CAE.

A general automotive car is majorly composed of high strength steel (6%), other steel (50%), Iron (15%), Plastics (7%), Aluminum (4%) and others (Rubber, Glass, Textile) about 18%. End-of-life vehicles (ELVs) are a significant source of waste and pollution in the automotive industry. Recycling ELVs, particularly their plastic components, Li-ion batteries, catalytic converters, and critical technology components such as alternators, semi-conductor chips, and high tensile strength steel can reduce their environmental impact and conserve valuable raw materials. The paper conducts a SWOT analysis and a life cycle assessment (LCA) to evaluate the long-term viability and potential of ELV recycling, environmental impact, and carbon footprint.

With the increasing competition in the automotive industry, customer experience & satisfaction is at the top of every organization's goals. The customers have evolved & NVH refinement has become the parameter for their decision making in buying a car. The major source of rumble noise in a vehicle is the induced vibrations due to combustion forces in an IC engine. These vibrations are then transferred to the vehicle body through engine mounts. Hence engine mounts play a key role in defining the NVH & the ride performance of any vehicle. However, it is infeasible to validate every mount design through the physical test as it will be both costly & time-consuming. But multiple design iterations can be verified by the CAE approach quite effectively. This paper focuses on the novel CAE approach to evaluate the mount vibrations due to engine dynamics. The process involves preparing a FEA model of the complete Powertrain system.

Valve train system is one major contributor to engine overall friction loss and is approximately 30% of total engine friction at lower speed and approximately 20 % at higher engine speed. Valve spring loads (preload and working) are proportional to friction loss of valve train. To optimizing the valve spring design main requirement is valve train perform it function safely at maximum engine cutoff RPM with minimum preload and working load. Robustness and frictional power loss are contradicting requirement, robustness demand high stiffness spring for better valve jump and bounce performance with dynamic safe valve spring design, on the other hand low frictional power loss demand for use of low stiffness spring. To optimize the valve spring stiffness for meeting both the requirement we need accurate prediction of valve spring in design stage and good correlation with testing data to reduce the number of iterations.

Radiators are one of the major components in the automotive engine cooling system. The road excitations from the frame to the radiator are dampened using rubber bushes. In this work, we analyzed a radiator sub-assembly with bushes by applying acceleration which are recorded at the center of gravity of the radiator. The radiator is considered as the concentrated mass which is attached to the upper and the lower radiator tank which is further connected to the frame through the bushings. An implicit transient dynamic analysis is set up. The hyper elastic coefficients for EPDM rubber are determined using the experimental data fit and structural damping coefficients are applied. When excited by the acceleration applied at center of the radiator component, the rubber bushes are deformed severely. Moreover, the analysis shows high strains in certain location on the upper bush where the part showed actual failure in the testing.

Fun to drive, pick-up of vehicle, high acceleration feeling of vehicle, time to reach max velocities are some parameters prevailing in the passenger vehicle market. In addition to focusing on information about fuel economy declared by manufacturer, the customer also has drivability related criteria in his mind. Although drivability is subjective, it can be judged by using various parameters like maximum speed, pick-up feeling, overtaking acceleration, time to reach 0 – 100 km/h or 0 – 60 km/h, etc. While comparing two vehicles of the same segment, one vehicle may perform better on some of the parameters while losses on others. To decide overall drive performance of a vehicle based on various measured performance related parameters, a methodology is defined. This will help to understand the overall performance of a vehicle holistically and to compare its performance with other vehicles in a better way.

In view of global concern for greenhouse gas emissions, need for greener and efficient Engines is increasing. Hence is it imperative that Internal Combustion Engines are improved in terms of efficiency to reduce Greenhouse gas emissions and meet CAFE targets. The cooling system of an ICE plays a major role in a vehicle performance. In this system, the radiator, thermostat, and cooling fan are the main components. Conventional cooling system uses Wax-type thermostat which is activated at specified coolant temperature and maintain same coolant temperature in fully warmed up condition at all engine operating points. Operative temperature selection in Wax-type is trade-off between engine friction & thermal efficiency at lower loads & knocking at higher loads. An electronic thermostat is a good alternative to maintain optimum temperature as per operating point requirement since optimum temperature at different operating points can be different.

In order to meet the challenges of future CAFE regulations & pollutant emission, vehicle fuel efficiency must be improved upon without compromising vehicle performance. Optimization of engine breathing & its impact on vehicle level fuel economy, performance needs balance between conflicting requirements of vehicle Fuel Economy, performance & drivability. In this study a Port Fuel Injection, naturally aspirated small passenger car gasoline engine was selected which was being used in a typical small passenger car. Simulation approach was used to investigate vehicle fuel economy and performance, where-in 1D CFD Engine model was used to investigate and optimize Valve train events (Intake and exhaust valve open and close timings) for best fuel economy. Engine Simulation software is physics based and uses a phenomenological approach 0-D turbulent combustion model to calculate engine performance parameters. Engine simulation model was calibrated within 95% accuracy of test data.

In a Passive suspension, a shock absorber generates damping force by pressurizing the oil flow between chambers. Typically, vehicle responds with suspension deflection, which significantly depends on damping forces and suspension velocity. Tuning dampers for various roads and steering input is an iterative balancing process. In any setting, damping force w.r.t velocity is tuned for optimum ride and handling performance. Practically, to achieve a balance between the two is a tedious task as the choices & arrangements of inner parts like piston, port, valve etc., which defines the forces set up [soft / hard] are almost infinite. The objective of this paper is to measure, objectify and evaluate the performance of two such optimum setting in various ride and handling events. A passenger car set up with an optimum soft & hard suspension damping force is studied for various ride and handling sub-attributes and their conflicts are examined in detail from a performance point of view:

The most widely used type of windshield wiper system employs a coil spring for wiper arm pressure generation. This spring is fixed between the arm head (fixed part) and wiper arm (moving part) and the tension in the spring is responsible for pressure generation. The present arrangement although being unsophisticated design, has following drawbacks: Inability to change wiper arm pressure according to change in vehicle speed. Inability to provide constant arm pressure during the complete range of motion along varying curvature of windshield. Inability to reduce/remove the continuous pressure on wiper blade when vehicle is parked for long durations resulting in permanent deformation of wiper blade rubber. This paper describes how electromagnets can be used to overcome the above stated inherent limitations of the windshield wiper system. An electromagnet is a device which produces magnetic field on application of electric current.

With strict upcoming regulation norms, it becomes a challenging task for automotive industry to develop highly efficient engine that meets all the regulation requirements. The focus of automakers is to utilize fuel energy in most efficient way and to reduce the energy loss from the engine to improve thermal efficiency. Heat loss to the cooling medium is one of the prime losses inside the combustion chamber. Thermal barrier coating is used to reduce heat losses across combustion chamber surfaces (Piston, head, valves and cylinder liner) as it provides good insulation because of the prominent properties of coating materials like low thermal conductivity, low heat capacity, high melting point etc. This paper presents application and impact of thermal swing coating on thermal efficiency. Thermal swing coating material follows gas temperature quickly throughout the cycle which reduces the temperature difference between gas and coating surface and thus reduces the heat loss.

In recent years, worldwide automotive manufacturers have been continuously working in the research of suitable technical solutions to meet upcoming stringent Real Driving Emission (RDE) and Corporate Average Fuel Economy (CAFÉ) targets, as set by international regulatory authorities. Many technologies have been already developed, or are currently under study by automotive manufacturer for gasoline engines, to meet legislated targets. In-line with the above objective, there are many technologies available in the market to expand lambda 1 (λ=1) region by reducing fuel enrichment at high load-high revolutions per minute (RPM) by reducing exhaust gas temperature (for catalyst protection) for RDE regulation [1]. Integrated Exhaust Manifold (IEM) is the key technology for the Internal Combustion (IC) for the subjected matter as catalyst durability protection is done by reducing exhaust gas temperatures instead of injecting excess fuel for cooling catalyst.

In the modern automobile scenario in developing countries, customers are getting more meticulous and market more competitive. Now even the budget vehicle customer expects desirable vehicle performance in specific use cases of the vehicle that were previously not focused by designers. Hence, the focus on perceived quality challenges automobile engineers to go the extra mile when it comes to the cost-effective design of parts that are tangible to the customer. A vehicle's cowl cover is one such exterior component. The primary functions of this part are to provide air intake opening for the HVAC system and cover the components like wiper motor. The aesthetic function is to cover the gaps between windshield, hood, and fender as seamlessly as possible. A specific role of cowl cover, which calls for a designer's attention, is its load-bearing capability.

Nowadays, Road Load Simulators are used by automobile companies to reproduce the accurate and multi axial stresses in test parts to simulate the real loading conditions. The road conditions are simulated in lab by measuring the customer usage data by sensors like Wheel Force transducers, accelerometers, displacement sensors and strain gauges on the vehicle body and suspension parts. The acquired data is simulated in lab condition by generating ‘drive file’ using the response of the above mentioned sensors. Due to non- linear nature of the vehicle parts, transmissibility of load is a complex phenomenon. Due to this complex transmissibility, good simulation at wheel center does not always ensure good correlation at all vehicle locations. The low level of correlation is common at the locations like engine mount, horn bracket and other overhanging brackets which are away from the wheel center.

The objective of this paper is to study the change in handling behaviour of the dual-fuel vehicle fitted with a CNG tank to that of its single fuel (gasoline) counterpart. A validated CarSim model is run through steady state and transient state handling tests before and after the addition of CNG tank. The simulation results are used to compare the handling characteristics of the CNG vehicle with the reference vehicle. Further based on these results the suspension parameters are changed to find an optimum set-up for the actual CNG vehicle.

To cater the push towards “Vehicle Light Weighting”, both sprung and unsprung mass are being reduced. This results in reduced stiffness and thus has a profound undesirable effect on the overall vehicle handling. To understand the effect of different reduction ratios of sprung to unsprung mass; it is desired to understand how changes in stiffness affect the overall vehicle handling characteristics. Therefore, the study was conducted to experiment with different values of roll stiffness, at both front and rear axles and comparing the frequency response and phase change of Yaw Gain observed through a Pulse Input test. The present work is further correlated with subjective feedback to predict the shift in vehicle balance and handling characteristics.

Fabrics play a vital role in defining the overall aesthetics of automotive interiors, primarily with fabric cleanliness. In this respect, the cleanliness of the fabric also becomes equally important. The fabric interior in a car is very prone to staining due to the spilling of water or any liquid substance over it. In order to protect and enhance the life of the fabric, various chemical treatments are suggested as fabric finishes. There are different chemical bases available for the same. Fluorocarbon base is the most effective treatment and is the focus of this study. This chemical treatment lowers the surface energy of the fabric by increasing the hydrophobicity of fabric. Hence, the liquid roll over the surface in the form of droplets by creating higher contact angle over the fiber surface. This study focuses on the effect of chemical treatment on the automotive fabric’s parameters, especially light color fabric.

The air pollution and global warming has become a major problem to the society. To counter this worldwide emission norms have become more stringent in recent times and shall continue to get further stringent in the next decade. From OEMs perspective with increased complexity, it has become a necessity to use simulation methods along with model based systems approach to deal with system level complexities and reduce model development time and cost to deal with the various regulatory requirements and customer needs. The simulation models must have good correlation with the actual test results and at the same time should be less complex, fast, and integrable with other vehicle function modelling. As the vehicle fuel economy is declared in cold start condition, the fuel economy simulation model of vehicle in cold start condition is required. The present paper describes a methodology to simulate the cold start fuel economy.

Electrostatic charge generation in fabric is a common phenomenon. This phenomenon of charge generation & transfer of the same to human body is more in case of fabrics made of polyester yarns due to interface property of the material. The charge generation may result in attraction of dust on the fabric surface, clinginess & may also result in uncomfortable shock to the human body. This situation is attributed to various parameters such as fabric construction, yarn properties, yarn finish & various coating on the yarn. Since, polyester fabric is prime material used in seating; there have been many incidences of rubbing of seat fabric to human body, resulting in generation of static charge. This study focuses on understanding the effect of various fabric parameters on electrostatic charge generation. The study will also look into various potential solutions to reduce the charge generation with their merits and demerits.

Aerodynamic evaluation plays an important role in the new vehicle development process to meet the ever increasing demand of Fuel Economy (FE), superior aero acoustics and thermal performance. Computational Fluid Dynamics (CFD) is extensively used to evaluate the performance of the vehicle at early design stage to overcome cost of proto-parts, late design changes and for time line adherence. CFD is extensively used to optimize the vehicle’s shape, profiles and design features starting from the concept stage to improve the vehicle’s aerodynamic performance. Since the shape of the vehicle determines the flow behavior around it, the performance is different for hatchback, notchback and SUV type of vehicles. In a hatchback vehicle, the roof line is abruptly truncated at the end, which causes flow separation and increase in drag.