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This paper describes vinyl ester based SMC (Sheet molding composite) material for oil sump part in automotive application. This sheet moulding composite is a ready to mould glass-fibre reinforced vinyl ester material primarily used in compression moulding process. This vinyl ester resin is compounded with glass fibre to meet the product functional requirements. Oil sump is a structural component under bonnet that forms the bottommost part of the crankcase and also contain the engine oil before and after it has been circulated through the engine. Generally, metals are preferred material for this application. In this paper, fibre filled vinyl ester based thermoset resin (SMC) material has been explored for oil sump application. They possess excellent properties in terms of tensile strength, modulus, impact strength, dimensional stability, high/low temperature resistance and oil resistance.

Digital human models (DHM) have greatly enhanced design for the automotive environment. The major advantage of the DHMs today is their ability to quickly test a broad range of the population within specific design parameters. The need to create expensive prototypes and run time consuming clinics can be significantly reduced. However, while the anthropometric databases within these models are comprehensive, the ability to position the manikin’s posture is limited and needs lot of optimization. This study enhances the occupant postures and their seating positions, in all instances the occupant was instructed to adjust to the vehicle parameters so they were in their most comfortable position. While all the Occupants are accommodated to their respective positions which finally can be stacked up for space assessments. This paper aims at simulating those scenarios for different percentiles / population which will further aid in decision making for critical parameters.

Squeak and rattle concerns accounts for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are major quality concern for automotive OEM’s. Objectionable door noises such as squeak and rattle are among the top 10 IQS concerns under any OEM nameplate. Customers perceive Squeak and rattle noises inside a cabin as a major negative indicator of vehicle build quality and durability. Door squeak and rattle issues not only affects customer satisfaction index, but also increase warranty cost to OEM significantly. Especially, issues related to door, irritate customers due to material incompatibilities. Squeaks are friction-induced noises generated by stick-slip phenomenon between interfacing surfaces. Several factors, such as material property, friction coefficient, relative velocity, temperature, and humidity, are involved in squeak noise causes.

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.

Passenger cars claim their presence in market by its pick up, top speed and maximum power of the engine. The study described in this paper is focused on improving the low-end performance of a 4-cylinder 1.6 L diesel engine while meeting the targeted maximum power. To meet the cause turbocharger works as an important element of the engine. A comparative study between regulated two stage turbocharger (R2S) and variable geometry turbocharger (VGT) shows that on a 4-cylinder engine VGT is superior by providing higher boost at 1000 engine rpm full load, than R2S, while in 3-cylinder (same displacement) the opposite effect can be seen. After simulations and iterations, it was confirmed that the in 4-cylinder the exhaust pulse cancellation were leading to a lesser exhaust energy at the turbine inlet. This pulse interaction leads to higher residual gas content which affects the low-end performance.

Technology is one of the key determinants of the outcome in today's wars. Many targeting systems today use infra-red imaging as a means of acquiring targets when ambient light is insufficient for optical systems. Reducing thermal signatures offers an obvious tactical advantage in such a scenario. One way to reduce thermal emission of combat vehicles is to adopt highly efficient electrical power trains instead of internal combustion engines that tend to reject a sizeable amount of the input energy as heat. The tractor is one of the most versatile vehicles that are used in the theatre of combat for various operations such as haulage, clearing terrain, deploying bridges, digging trenches etc due to its excellent abilities in handling difficult terrain. A tractor powered by an all-electric power train was developed for civilian applications. The traction characteristics are identical to that of a conventional diesel powered tractor of comparable size.

Automotive clutches are rotary components which transmits the torque from the engine to the transmission. During the engagement, due to the difference in speed of the shafts the friction lining initially slips until it makes a complete engagement. Enormous amount of heat is generated due to the slippage of the friction lining, leading to poor shift quality and clutch failure. Depending on the road & traffic conditions, and frequency of engagement and disengagement of the clutch, it generates transient heating and cooling cycles. Hill fade test with maximum GVW conditions being the worst case scenario for the clutch. A test was conducted to understand the performance of the clutch, in which clutch burning was observed. The clutch lining got blackened and burning smell was perceived. The friction coefficient drops sharply to a point until it cannot transmit the torque required to encounter the slope. This further worsen clutch slippage and lead to more severe temperature rise.

This paper is an attempt to compile a systematic approach which can be easily incorporated in the product development system used in the design and development of parking brake systems for passenger cars having rear drum brakes, which in turn can effectively reduce the lead time and give improved performance. The vehicle GVW, percentage gradient and maximum effort limits (as per IS 11852 - Part 3), tire and drum brake specifications were taken as front loading. This data is used for target setting of functional and engineering parameters, such as lever pull effort, lever ratio and angular travel of lever. Design calculations were performed to obtain theoretical values of critical parameters like lever effort and travel. The comparison between target and theoretical values give the initial confidence to the system engineer. Further, the outcome was taken to conceptualize the hard points of lever on vehicle for ergonomics.

An inadequate sealing of the combustion chamber gasket interface may have severe consequences on both the performance & emission of an engine. In this investigation, both the distribution of the contact pressure on the gasket and the stresses of the cylinder head at different loading conditions are explored and improved by modifying the design. A single cylinder gasoline engine cylinder head assembly has been analyzed by means of an uncoupled FEM simulation to find the sealing pressure of the multi-layer steel (MLS) gasket, strength & deformation of the components involved. The thermal loads are computed separately from CFD simulations of cylinder head assembly. The cylinder head assembly consisting of head, blocks, liner, cam shaft holder, bolts, gaskets, valve guides & valve seats, is one of the most complicated sub-assembly of an IC engine.

In automotive product development, design and development of the chassis plays an important role since all the internal and external loads pass through the vehicle chassis. Durability, NVH, Dynamics as well as overall vehicle performance is dependent on the chassis structure. Even though passenger vehicle chassis has a ladder frame or a monocoque construction, small commercial vehicle chassis is a hybrid chassis with the cabin welded to the ladder frame. As mileage is critical for sale of SCVs, making a light-weight chassis is also important. This creates a trade-off between the performance and weight which needs to be optimized. In this study, a parametric beam model of the ladder frame & the cabin of the vehicle is created in COMSOL Multiphysics. The structure has been parameterized into the long member & crossmember geometry & sections. The model calculates the first 12 natural frequencies, global stiffness, and weight.

Light weighting in modern automotive powertrains call for use of plastics (PP, PA66GF35) for cam covers, intake manifolds and style covers, and noise encapsulation covers. Conventionally, in early stage of design these components are evaluated for static assembly loads & gasket compression loads at component level. However, engine dynamic excitations which are random in nature make it challenging to evaluate these components for required fatigue life. In this paper, robust methodology to evaluate the fatigue life of engine style cover assembly for random vibration excitations is presented. The investigation is carried out in a high power-density 4-cylinder in-line diesel engine. The engine style cover (with Polyurethane foam) is mounted on cam cover and the intake manifold using steel studs and rubber isolators to suppress the radiated noise.

Tractor weight transfer is the most common farm-related cause of fatalities nowadays. As in India it is getting mandatory for all safety devices across all HP ranges. Considering any changes in the weight from an attachment such as Rops, PTO device, tow hook and draw bar etc. can shift the center of gravity towards the weight. center of gravity is higher on a tractor because the tractor needs to be higher in order to complete operations over crops and rough terrain. Terrains, attachments, weights, and speeds can change the tractor’s resistance to turning over. This center of gravity placement disperses the weight so that 30 percent of the tractor’s weight is on the front axle and 70 percent is on the rear axle for two-wheel drive propelled tractors and it must remain within the tractor’s stability baseline for the tractor to remain in an upright position.

With recent advancements to create light weight engines and therefore, to design stronger and lighter connecting rods, automobile manufacturers have looked upon vanadium micro-alloyed steels as the material of choice. These materials have been developed keeping in mind the strength and manufacturing requirements of a connecting rod. Since, 36MnVS4 has been the most popular of this category, the same has been discussed in this paper. The transition of manufacturers from the traditional C70S6 grade to the new 36MnVS4 must be dealt with in-depth study and modification of processes to adapt to new properties of the latter. C70S6 is a high carbon grade with superior fracture split whereas 36MnVS4 is a medium carbon grade with superior strength and ductility owing to the presence of vanadium.

Overall in-vehicle visibility is considered as a key safety parameter essentially mandated due to the increasing traffic scenario as seen in developing countries. Driver side bottom corner visibility is one such parameter primarily defined by A-pillar bottom and outside rear-view mirror (OSRVM). While defining the OSRVM package requirements such as size, position and regulatory aspects, it is also vital to consider other influencing parameters such as position of pillars, waist-line height, and Instrument panel which affect the in-vehicle visibility. This study explains the various package considerations, methods to optimize OSRVM position, shape and housing design in order to maximize the in-vehicle visibility considering the road and traffic conditions. A detailed study on in-vehicle visibility impacted by OSRVM packaging explained and had been verified for the results.

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.

In addition to performance target, recent stringent emission legislation and reduction in oil consumption are the major driving force for engine design and development. In this reference importance of crankcase ventilation has increased immensely and the manufacturers are bound to develop most efficient system with high oil trap efficiency. In crankcase ventilation system, the blow-by gases from the crankcase are routed to the intake manifold through Oil separator system. The oil separator task is to retain the oil part from the blow by gas and send it back to sump. Developing an oil separator for the engine studied here was very challenging considering double stage turbocharger which produces very fine mist of oil and is difficult to separate. The study shows that oil mist coming in blow by is of size 0.3 micron and lesser than it. The major contribution of these fine mists was from turbocharger.

Vehicles with manual transmission are still the most preferred choice in emerging markets like India due to their benefits in cost, simplicity and fuel economy. However, the ever-increasing vehicle population and traffic congestion demand a smooth clutch operation and a comfortable launch behaviour of any manual transmission vehicle. In the present work, the launch performance of a sports-utility vehicle (SUV) equipped with dual mass flywheel (DMF) and self-adjusting technology (SAT) clutch could be improved significantly by optimizing the clutch system. The vehicle was observed to be having a mild judder during clutch release (with 0% accelerator pedal input) in a normal 1st gear launch in flat road conditions. An extensive experimental measurement at the vehicle level could reveal the launch judder is mainly due to the 1st order excitation forces created by the geometrical inaccuracy of the internal parts of the clutch system.

Vehicle frame evaluation at early stages of product development cycle is essential to reduce product turnaround time to market. In conventional approach of virtual validation it is required to evaluate the strength of the vehicle structure to account for the standard Service Load Analysis (SLA) loading conditions. But this paper describes on the strength analysis of scooter frame with derivation of critical static load cases. The critical load cases are extracted from the load-time history while the vehicle was simulated on durability virtual test rigs which is equivalent to proving ground tests. This methodology gives the better accuracy in prediction of stress levels and avoids the overdesign of components based on traditional validation technique. There is significant drop in stress levels using the critical load case approach as compared to conventional load case method.

Plenum is the part located between the front windshield and the bonnet of an automobile . It is primarily used as an air inlet to the HVAC during fresh air mode operation. It’s secondary functions include water drainage, aesthetic cover to hide the gap between windshield to bonnet, concealing wiper motors and mechanisms etc. The plenum consists mainly two sub parts viz. upper plenum and lower plenum. Conventional plenum design which is found in majority of global OEMs employ a plastic upper plenum and a metal lower plenum which spans across the entire width of engine compartment. This conventional lower plenum is bulky, consumes more packaging space and has more weight. In this paper, we propose a novel design for the plenum lower to overcome above mentioned limitations of the conventional design. This novel design employs a dry and wet box concept for its working and is made up of complete plastic material.

The Ride Comfort has always been an important attribute of a vehicle that gets trade-off with handling characteristics of a vehicle. However, to cater the growing customer requirements for better ride comfort in a vehicle without compromising on other attributes, evaluating and achieving optimal ride comfort has become a significant process in the vehicle development. In the current engineering capability and virtual engineering simulations, creating an accurate and real time model to predict ride comfort of a vehicle is a challenging task. The qualitative evaluation of ride attributes has always been the proven conventional method to finalize the requirements of a vehicle. However, quantitative evaluation of vehicle ride characteristics benefits in terms of target setting during vehicle development process and in robust validation of the final intended product against its specifications.