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Continuously rising fuel prices and global concern on climate change have resulted in a need to deliver vehicles with increased fuel economy. This has to be achieved without compromising on performance, durability and cost. Passenger car manufacturers are looking at various ways to maximize fuel economy. Major part of fuel saving can be tapped from engine itself. This can be done by activities on engine as below: Improving overall combustion efficiency and hence BSFC Efficient thermal management. Weight reduction of engine parts or complete downsizing Hybridization. Reducing engine losses i.e. parasitic losses from auxiliaries and frictional losses. This paper is focused on the reduction of engine frictional losses (FMEP) through the use of low viscosity lubrication oils. Various factors in lubrication oil contribute to friction. Experimental approach to quantifying the effect of different parameters of lubrication oil on total engine friction is presented.

Hexavalent chromium Cr(VI) is recognized as a known human carcinogen via inhalation. This is banned to be used in Corrosion Protective Coatings as per End Life of Vehicle regulation (ELV) 2000/53/EC effective July'07 in EU. Traditionally all automotive metallic components which are Zinc plated are passivated with a thin Chromate layer to add to its brightness and protect it from premature corrosion. These Chromate coatings (or passivation) are generally Hexavalent chromium based and available in four grades: clear, yellow, olive drab, and black. Alternatives in the form of Trivalent Chromium Cr(III) are now available. By nature, both these passivations have different properties. Trivalent chromium has high temperature resistance but low wear resistance thus does not possess self healing properties. Also, its cost is significantly higher compared to hex chrome solutions.

Downsizing of engines is becoming more popular as manufacturers toil for increased fuel economy. Due to the downsizing of engines, Brake Mean Effective Pressure (BMEP) tends to increase, which in turn increases the heat release from engine. This necessitates the need for optimizing cooling system in order to get higher engine output and lower emissions to comply with stringent emission norms. In earlier engines, thermo-siphon principle was used with water as the coolant. This has been replaced in modern engines with pressurized cooling system with coolants like ethylene glycol mix. Along with the conventional objective of increased material durability with the optimized engine cooling system, it has been found that there is an improvement in the engine output due to increased charging efficiency. This paper describes the effect of engine coolant temperature on performance, emission and efficiency of a three-cylinder naturally aspirated spark ignited engine.

In automotive seating system, seat upholstery quality has an important role in defining the overall quality and aesthetics of vehicle interiors. Technical textiles for seating system used in automotive applications are generally categorized into woven or knitted type. An automotive textile material is a composite material made up of three layers; base fabric (top layer), foam (middle layer) and scrim (bottom layer) as shown in Fig. 1. There are many challenges to be overcome during development of fabric e.g. mechanical, physical and aesthetic issues have an impact on overall seat quality, appearance and performance. These issues get highlighted during testing, which takes place during development stage of fabric. The concerns mentioned above are found in automotive textiles in both woven and knitted types of fabrics sourced from different manufacturing set-ups. This paper focuses on identification of problems during testing, followed by root cause analysis.

Front end accessory drive (FEAD) system explained in this paper is a sub-system of an engine. In FEAD system, a poly-v belt is used to drive the alternator and water pump by transmitting power from crankshaft pulley. In a new vehicle development program, durability targets of FEAD system are based on required life of poly-v belt, its static tension readjustment interval and replacement frequency. To meet these durability targets following methodology is applied in design stage:- 1 Simulation of FEAD system to calculate the theoretical life of belt 2 Part level testing of belt as per SAE J2432 These methods give sufficient information on belt durability. However in actual usage, certain failures are prone to happen and enormous difference is always observed between theoretical and actual life of belt. This paper describes the traditional stair-case approach followed to optimize the FEAD system based on the outcome of durability tests.

The durability evaluation of overhanging components of a vehicle (Ex: horn, radiator) is a challenge to durability engineers as resonance plays an important role in determining their fatigue life. As resonance cannot be avoided always, it is desirable to develop methods to evaluate life of the component in the presence of resonance. Though the existing vibration test standards suggest test profiles to evaluate resonance failures, there are cases in which, these methods do not yield the proving ground results. This may lead to unnecessary overdesign or unrealistic failures. In such cases it is suggested to generate a sweep endurance test procedure customized to the proving ground or actual roads. This paper studies a methodology for generating a sweep endurance test procedure for evaluation of resonating components. Responses like stress and accelerations were measured in test components in proving ground. Contribution of each frequency band towards overall damage is determined.

As emissions standards become more stringent, OEMs are pushing engines to run on leaner fuel mixtures, which puts increased thermal stress on components, particularly pistons, causing them to operate at higher temperatures. This requires more robust design and rigorous testing of components. Telemetry methods offer accurate and real-time feedback, allowing designers to test components at various operating conditions, providing more flexibility than other traditional methods. Piston temperature measurement is a critical aspect of engine development because it directly affects engine performance and durability. Among the various techniques available for this purpose, telemetry methods have gained considerable attention in recent years. This method involves integrating temperature sensors and transmitter on the piston, which transmit temperature data wirelessly to a receiver outside the engine.

Increased engine thermal load, front end styling and compact vehicle requirements have led to significant challenges for vehicle front end designer to provide innovative thermal management solutions. The front end cooling module design which consists of condenser, radiator, fan and intercooler is an important part of design as it ensures adequate heat removal capacity of radiator over a wide range of operating conditions to prevent overheating of engine. The present study describes the optimization of cooling air flow opening in the front end using CFD methodology of a typical passenger car. The predicted vehicle system resistance curve and coolant inlet temperature to the radiator are used for the selection of cooling modules and to further optimize the front end cooling opening area. This leds to the successful optimization of the front end, selection of cooling modules with significant cost savings by reducing prototype testing and design cycle time.