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With advancement of technologies, upgradation of validation procedures and equipment on engine dynamometer test bed is required to simulate environment similar to vehicle and achieve accurate test results. A coolant conditioning system helps in achieving desired temperatures of coolant in the circuit during engine validation. However, unlike radiator type cooling systems of vehicles, conventional coolant conditioning systems on engine test beds generate negative pressure in circuit which poses a risk of coolant boiling, loss of intended heat transfer and hence higher temperature in cylinder head which can be detrimental for durability of critical components like valves, valve seats etc. This paper encompasses a stepwise approach followed to attain near-vehicle coolant pressure conditions for a naturally aspirated engine. Coolant used for this experiment was 50:50 (by volume) ethylene glycol and water mixture.

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.

Three-cylinder Engine without balancer shaft is a recent trend towards development of lightweight and fuel-efficient powertrain for passenger car. In addition, customer's expectation of superior NVH inside vehicle cabin is increasing day by day. Engine mounts address majority of the NVH issues related to transfer of vibration from engine to passenger cabin. Idle vibration isolation for a three-cylinder engine is a challenging task due to possibility of overlapping of Powertrain's rigid body modes with engine's firing frequency. This Overlapping of rigid body can be avoided either by modifying mount characteristic or by changing the position of mounts based on multi-body-dynamics (MBD) simulation. This paper explains about two types of engine mounting system for a front-wheel drive transversely mounted three-cylinder engine. The base vehicle was having three-point mounting system i.e. all three engine mounts were pre-loaded.

Automobile exhaust systems help to attenuate the engine combustion noise as well as the high frequency flow noises which are generated as the gas expands and contracts through various ducts and orifices of muffler system. One of the solutions to mitigate the noise generated due to the latter is by means of an absorptive muffler, comprising a fibrous acoustic medium which helps to absorb noise of certain frequencies which are sensitive to the human ear. Typically, the construction of such a system consists of the fibrous acoustic medium encompassing a perforated inner pipe on the inside and enclosed by an outer metal case on the outside. The temperature limitations of the acoustic medium sometimes necessitate the placement of the fibrous acoustic system away from the engine source in order to prevent any damage to the fibers upon direct contact with the flue gas.

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.

In automotive Front End Accessory Drives (FEAD), the crankshaft supplies power to accessories like alternators, pumps, etc. FEAD undergoes forced vibration due to crankshaft excitation, dynamic tension fluctuations can cause the belt to slip on the accessory pulleys. By considering the criticality of the system, when engine mounting is longitudinally to the vehicle which makes it directly exposed to the air flow containing foreign particles which may cause the damage to the FEAD system and deteriorate the intended functionality. FEAD cover is introduced in the system to enhance belt-pully system functionality by restricting the entry of foreign particles during engine operation. This paper contains a study of FEAD cover failure and provides the stepwise approach to capture such issue during novel model development for 4 cylinder naturally aspirated engine during engine bench testing.

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.

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.

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.

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.

Rapidly changing emission and fuel efficiency regulations are pushing the design optimization boundaries further in the Indian car market which is already a very cost conscious. Fuel economy can be improved by reducing moving parts friction and weight optimization. Driveline or Transmission power losses are major factor in overall efficiency of rotating parts in a vehicle. Transmission efficiency can be improved by using low viscosity oil, reducing oil quantity and reducing churning losses in car transmission. Changes like low viscosity and reduced oil volume give rise to challenges like compromised lubrication and durability of rotating parts. This further leads to extended design cycles for launching new cars with better transmission efficiency and fuel economy into the market. Design cycle time can be reduced by using CFD simulation for oil flow validation in the early design stage.

Vehicles in India will soon come with star ratings, signifying how environment-friendly they are. The OEM's have braced to improve fuel economy of their existing & upcoming models. Tyre rolling resistance is one of the significant factors for vehicle fuel consumption. Improvement in Fuel consumption is always a prime focus area & to improve it all major factors are considered. In newly launched models, the low rolling resistance tyre development was initiated. The project is challenging as it requires not only achieving low rolling resistance in smaller size tyres (12″ to 13″) but also required to meet other critical vehicle performance parameters like ride, handling, NVH & durability. Effects of Tyre construction, rubber compound were analyzed to achieve lower rolling resistance and better durability of tyre. In addition, the factors affecting the rolling resistance of tyre like inflation pressure, load, and speed in smaller tyre sizes (12″ to 13″) are discussed in this paper.

NVH refinement of passenger vehicle is essential to customer acceptance for premium or even mid-size segment passenger cars. Hydraulic engine mount is becoming common for these segments to reduce engine bounce, idle shake and noise transfer to passenger cabin. Modern layout of hydraulic mount with integrated engine-bracket and smaller size insulator has made it cost-effective to use due to reduction of cost gap from conventional elastomeric mounts. However the downsizing and complex internal structure may create some new types of noises in passenger cabin which are very difficult to identify in initial development stage. Main purpose of hydraulic mount is to provide high damping at low-frequency range (6~15 Hz) and to isolate noise transfer from combustion engine to passenger cabin within wide frequency range (15~600 Hz).This paper emphasizes on challenges and problems related to hydraulic mount development.

India is a country of diversity. From North to South, east to west, one can find altogether different culture, religions, spoken languages, foods, weather conditions, people lifestyles, dressing styles etc. This vast diversity of India poses a great challenge in front of Indian Automobile Manufacturers, so as to assimilate all the requirements (of this big nation) in one single car (design). For example, many people in India wear turban (out of their religious beliefs or cultural heritage). So, is it required to keep enough consideration for Turban wearing population in vehicle design? Turban, unlike caps or hats, is something which is tied on the head (not just only kept). It is something which cannot be removed whenever required. So, it can somehow be considered as an integral part of body (as an added head dimension). So, it becomes all the more important to thoroughly understand this aspect & keep a consideration for the same in vehicle design.

Global automobile market is very sensitive to vehicle fuel economy. Gross vehicle weight has substantial effects on FE. Hence, for designers it becomes utmost important to work on the weight reduction ideas up to single component level. Fuel delivery pipe (Fuel Rail) is one such component where there is a big potential. Fuel rail is an integral part of the vehicle fuel system and is mounted on the engine. Primarily it serves as a channel of fuel supply from fuel tank through fuel lines to the multiple fuel injectors, which further sprays the fuel into intake ports at high pressure. Due to opening and closing of injectors, pulsations are generated in fuel lines, so fuel rail also acts as a surge tank as well as a pulsation damper. All these factors make the design of a fuel rail very critical and unique for a particular engine. Materials like aluminum, plastic and sheet metal are generally used for fuel rail manufacturing.

Quieter cabins are indispensable in today’s evolving automobile industry. The effective isolation of vehicle noise and vibrations are essential to achieve the above. Since, low frequency powertrain induced NVH has been one of the major contributors affecting noise and vibration levels inside the passenger cabin. Thus, use of hydraulic mounts is a natural choice for all major OEMs. The objective of this study is to optimize the design of the hydraulic mount de-coupler unit, to reduce the abnormal noise felt inside the cabin. This condition was observed when the vehicle was driven at 20~30 km/h over undulated road surface, found very often in Indian drive conditions. Due to lack of accuracy and repeatability errors during NVH data acquisition in actual driving condition, the above road profile was captured and subsequently simulated in an acoustically treated BSR (Buzz, Squeak and Rattle) four poster simulator.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. Working on global platform is challenging in order to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and, at the same time, to meet the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper: a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

As the automotive market is very dynamic and vehicle manufactures try to reduce the vehicle development cycle time, more focus is being given to CAE simulation technologies to reduce the design cycle time and number of physical tests. CAE engineers are continuously working on improving the accuracy of CAE simulation, such as using flexible body dynamic simulation in place of linear static analysis. Strength calculation under dynamic condition is more accurate as compared to static condition as it gives more clear understanding of stress variation with motion, contacts and mass inertia. Failure has been observed in new development of valve train pivot screw under test conditions. As per linear static analysis, design was judged OK. Normal linear static analysis is a two stage process. In first stage loads are calculated by hand or peak loads are taken from multibody dynamics (MBD) rigid body analysis.

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.

The interface between human body and automotive seat contours is seat upholstery. Seating comfort has a functional correlation to the upholstery. Two seats having different upholstery will give different comfort perception. Even an ergonomically designed seat if fitted with poor quality fabric will subdue the seat comfort drastically. The effect of fabric comfort ranges from initial short term to long term comfort, driven by properties like wick-ability and factors like thermal stress. Beyond material characteristics, fabric fit also plays an important role. This paper analyses the effect of fabric parameters and construction on automotive seat comfort. A comprehensive comparative study is followed by systematic analysis and comfort improvement scope through upholstery. The research is to conclude potential of the seat fabric in enhancing the automotive seating comfort within stipulated constraints of fabric properties and cost.