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In recent years, the push for reduced product development timelines has been more than ever with significant changes in the automotive market. High electrification, intelligent vehicle systems and increased number for car manufacturers are a few key drivers to the same. The front loading of development activities is now a key focus area for achieving faster product development. From vehicle dynamics point of view availability of subjective evaluation feedback plays a key role in optimization various system specifications. This paper discusses an approach for front loading through parallel development of the tire and vehicle chassis system, using advanced simulation and driving simulator technology. The proposed methodology uses virtual tire models which in combination with real-time vehicle model enables subjective evaluation of vehicle performance in driver-in-loop simulators.

Automotive OEMs are aggressively using different materials for interiors due to value proposition and variety of options available for customers in market. Excessive usage of different grade plastics with zero gap philosophy can cause stick slip effect leading to squeak noise. Even though systems and subsystems are designed using best practices of structural design and manufacturing tolerances, extreme environmental conditions can induce contacts leading to squeak noise. Appropriate selection of interface material pairs can minimize the possibilities of squeak conditions. Stick-slip behavior of different plastics is discussed in the present study, along with critical parameters during material compatibility testing in a tribological test stand. Friction coefficient of different material pairs for a defined normal load and sliding velocity are analyzed for patterns to recognize squeaks versus time.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. The engine cooling system plays a vital role in meeting the stringent emission norms and improving the vehicle fuel economy apart from maintaining the operating temperature of engine. The airflow through vehicle subsystems like the grille, bumper, the heat exchangers, the fan and shroud and engine bay are called as front-end flow. Front end flow is crucial factor in engine cooling system as well as in determining the aerodynamic drag of vehicle. The airflow through the engine compartment is determined by the front-end vehicle geometry, the CRFM and CAC package, the engine back restriction and the engine compartment geometry including the inlet and outlet sections. This paper discusses the 1D modelling method for front-end airflow rate prediction and thermal performance by 1D method. The underbody components are stacked using heat stack and simulated in pressure mode.

Light weighting is an effective strategy in increasing energy efficiency in the automotive industry. In this paper, mass reduction with cost benefit was targeted in an exterior trim panel. Polypropylene copolymer (PPCP) compound was developed for a large exterior trim panel (1400 X 700mm) having an integrated grill mesh. The part had challenging requirements in terms of slow speed impact, structural durability, dimensional stability, aesthetics, thermal ageing resistance, cold impact resistance, scratch resistance and weathering resistance. By having ultra-high flow behavior, optimum tensile strength, modulus, impact strength and thermal properties, the PPCP compound met the requirements for a thin wall exterior trim panel with a thickness of 2.6mm. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis.

In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

Turbocharged common rail direct injection engines offer multiple benefits compared to their naturally aspirated counterparts by allowing for a significant increase in the power and torque output, while simultaneously improving the specific fuel consumption and smoke. They also make it possible for the engine to operate at a leaner air/fuel mixture ratio, thereby reducing particulate matter emission and permitting higher EGR flow rates. In the present work, a two cylinder, naturally aspirated common rail injected engine for use on a load carrier platform has been fitted with a turbocharger for improving the power and torque output, so that the engine can be used in a vehicle with a higher kerb weight. The basic architecture and hardware remain unchanged between the naturally aspirated and turbocharged versions. A fixed geometry, waste gated turbocharger with intercooling is used.

The present work discusses the developed simulation model aimed to predict the heat rejection (HR) performance and external pressure drop characteristics of automotive charge air cooler (CAC). Heat rejection and airside pressure drop characteristics of CAC were predicted for the conditions of different charge air mass flow rates and different cooling air velocities. The lack of detailed research on CAC performance prediction has motivated the development of the proposed simulation model. The present 1-D simulation has been developed based on the signal library of AMESIM application tool. Input parameters for this simulation such as core size, tube pitch, tube height, number of tubes, fin density, louver angle, louver pitch, charge air mass flow rate, cooling air velocity, charge air inlet temperature, and ambient temperature. Heat rejection curve and airside pressure drop of CAC were the output of the present simulation.

With the advancement in vehicle technology over the years, many intuitive technologies are coming in automotive passenger vehicles to improve the safety aspects during vehicle driving in night conditions. In addition to headlamps, cornering lamps or infrared camera with head up display etc. are evolving as a part of AFS (Advanced Front Lighting Systems) to aid driver vision. Many OEMs are following conventional methodology of subjective assessments with the ratings on different numerical scale mapped with customer acceptance to validate head lamps and its tech updates. These methods lag in getting repeatability of results, acceptance reliability and not knowing the limitations of the installed system due to high dependency on the selected evaluators. This paper emphasizes on robust test methodology development to validate the complete performance of cornering lamps with the objective test data analysis.

With increasing growth of vehicular population, there is an increasing demand for raw materials. This has added strain to the available resources, which is becoming more and more unsustainable. As a result, search for sustainable materials are continuously happening in our industry and there is a strong focus from everyone to incorporate more and such materials. One way of doing so, is by blending naturally available materials like fibers, with polymers. In this study, naturally available Coconut fibers have been blended successfully with Polyurethane foam, thereby improving the green footprint of the vehicle. Coconut fibers are naturally occurring fiber extracted from the husk of the coconut. Polyurethane foam is the most versatile polymeric foam used in several places of automobile for reducing the Noise, Vibration & Harshness. The composite was manufactured using reaction injection molding technique by reacting polyol with iso-cyanide.

This study on optimum magnification at which Retained austenite to be evaluated by comparing the difference in determining the retained austenite in low carbon carburizing alloy steel using the optical metallurgical micrographic method and X-ray diffraction method. The retained austenite phase will be in surface and color is white in nature also its presented in between the martensite needles. It can be distinguished as separate micro-constituents by using image analyzing software. In another method the RA measurements were carried out on the surface by PROTO iXRD Retained austenite measuring system using Cr K radiation. The (211) and (200) reflections of Martensite and (220) and (200) reflections of Austenite were made for this estimation. However, the calculated values of retained austenite by metallurgical microscope in different magnifications are not identical.

Increase in customer's awareness for better vehicle NVH has prompted automobile industry to address NVH issues more seriously. Among other critical vehicle systems for NVH, Air Intake and Exhaust Systems play an important role in terms of passenger compartment noise, sound quality and vehicle pass-by noise. Hence proper design & development of these systems is imperative to reduce their contribution in overall vehicle NVH. This needs to be achieved within constraints of meeting other functional requirements such as emissions and engine performance. The design parameters one needs to look at while developing the intake and exhaust system are mainly the acoustic transmission loss, structural noise radiations from the surfaces and structural isolation between body and these systems. This paper demonstrates the use of FEM approach for Vibro-Acoustic Analysis as a practical means for design of intake and exhaust system in terms of high transmission loss.

Electric Vehicle is the need of an hour, as due to excessive usage of IC Engine vehicles has resulted in the depletion of the ozone layer to a significant level and fuel cost is increasing. With new technologies coming into the market, challenges come hand in hand because of Electric Vehicle. In comparison to IC Vehicle, areas of thermal management or the number of components for which thermal management needs to be done is higher and rather complex. As the thermal management system is the second highest energy consuming source after the powertrain of the electric vehicle, an efficient and reliable design is mandatory to ensure better range in an Electric Vehicle. Thermal Management of the Electric Vehicle has been identified as one of the critical parameters for balancing both cabin comfort as well as Battery temperature. One of the major concerns is meeting the Cabin comfort during colder weather with minimum energy consumption.

Serious efforts have been put in space to focus on lowering the fuel consumption and CO2 discharge to the environment from Automotive Diesel Engines. Though more focus is put on material up gradation approach on weight perspective, it is accompanied by undesirable cost increase and manufacturing complexity. As a part of development of a single cylinder engine for a light commercial vehicle application, a unique approach of integrated split type crankcase design is designed and developed. This design have addressed all the key factors on Weight, Cost and Manufacturing perspectives. The split type crankcase configuration, particularly middle-split configuration, integrates the oil sump, front cover and flywheel housing in a single unit beneficial from the point of view of reducing engine weight and thus reducing the manufacturing costs. This crankcase is also excellent from the serviceability point of view.

The noise and vibration performance of diesel fueled automotives is critical for overall customer comfort. The stationary vehicle with engine running idle (Vehicle Idle) is a very common operating condition in city driving cycle. Hence it is most common comfort assessment criteria for diesel vehicles. Simulations and optimization of it in an early stage of product development cycle is priority for all OEMs. In vehicle idle condition, powertrain is the only major source of Noise and Vibrations. The key to First Time Right Idle NVH simulations and optimization remains being able to optimize all Transfer paths, from powertrain mounts to Driver Ear. This Paper talks about the approach established for simulations and optimization of powertrain forces entering in to frame by optimizing powertrain mount hard points and stiffness. Powertrain forces optimized through set process are further used to predict the vehicle passenger compartment noise and steering vibrations.

Present day AMT unit uses two high pressure hydraulically operated pistons for select & shift operations which make the unit weigh around 8kg. Besides this it also makes the unit more complex & unreliable with a lot of torque interruption. The use of electrical servo motors steps in here as a better alternative as it provides a more precise and smoother shift. To test this we used a 5-MT Transmission. For the selection, a precise 14.5 degree of twisting was required which was easily achieved by the servo motor. Further, shift of 10.5mm could be made possible by using the motor to shift the rack using a pinion on the shaft. This system then essentially eliminates the whole hydraulic circuit, the housing of actuator pack & power pack making it a simpler unit all together. Thus, it offers an uninterrupted torque path from the engine to vehicle which allows for a seamless gearshift. This seminal paper provides an introduction to the technology together.

Noise & sound quality has gained equal importance as that of emissions and crash safety of the vehicles. With increased engine power to weight ratio, the challenges for NVH engineers has increased multifold. Passenger compartment comfort levels are getting affected largely due to lighter and powerful engines. Same time, there is pressure to reduce overall vehicle weight and cost. This impose constraints to NVH engineer in designing the body structure and sound package to reduce the effect of powertrain forces and airborne noise on passenger compartment. In addition to weight constraints, there is trend emerging to use two & three cylinder engines which need to perform on par with four cylinder engines. This has shown adverse effect on vehicle NVH performance due to wider low frequency unbalance forces.

This paper describes modified polypropylene copolymer (PPCP) material for thin wall front bumper development (2.5 mm) with integrated grill in automotive application. This compounded PPCP material has optimized flow behavior, tensile strength, modulus, impact strength, and thermal properties to meet the functional requirements. This is a ready to mold material used in injection molding process. Front bumper and grill are functional components with slow speed impact requirement to absorb impact in real world. These parts have precise fitment requirement under sun load condition. Front bumper is also having other critical criteria with respect to vehicle variants such as aesthetic mold-in-color finish as well as painted finish. Grill has air entry performance criteria to ensure cooling efficiency in intercooler compartment.

This paper describes modified polypropylene copolymer (PPCP) material for canopy plastic structure in a modular commercial passenger vehicle. This compounded PPCP material has optimized flow behavior, tensile strength, modulus, impact strength, and thermal properties to meet the functional requirements. Material described in this paper is a PPCP compound reinforced with glass fiber and mica filler. The application described in this paper is a canopy plastic structure, which is a structural exterior plastic part. Canopy plastic structure acts as a structural frame to hold vinyl canopy in both sides and tail gate of vehicle. In this paper, PPCP has been explored for canopy plastic structure part against conventional polyamides. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis.

Reducing the mechanical friction of internal combustion engines could play a major role in improving the brake specific fuel consumption (BSFC). Hence, it is important to reduce the friction at every component and sub-system level. In the present work, the oil pump friction of a 1.5 liter 4-cylinder diesel engine is optimized by reducing the oil pump displacement volume by 20%. This could be achieved by adopting an optimized oil supply concept which could reduce the oil leakage through the main bearings and connecting rod bearings. A 1-dimensional oil flow simulation was carried out to predict the oil flow distribution across the engine for different speeds. The results indicate that the oil leakage through the main bearings and connecting rod bearings contribute to ~25% of the total oil flow requirement of the engine. In a conventional oil supply concept, the big-end bearing of each connecting rod is connected to the adjacent main bearing through an internal oil hole.

As customers are inching towards adoption of electric vehicles as an alternative to internal combustion engines, automotive OEM’s will have to embrace this change and equip with new product development process. When it comes to Electric Vehicle (EV) in comparison with Internal Combustion Engine (ICE), NVH plays a major differentiator for vehicle refinement. Squeak and rattles will account for 20-25% of overall in-cabin noise source in an electric vehicle, most of which is observed from interior trims. Trims are mounted using small plastic clips which function as attachments and play a significant role in part retention and part integrity during normal operation and in case of any transient events. The engineering specifications for selecting a clip is force in newtons and it is mostly driven by ease of assembly, serviceability, and durability. A single DOF system with a specimen mass is developed and stiffness and damping are calculated based on transmissibility.