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Reactivity Controlled Compression Ignition (RCCI) is a promising, high-efficiency, clean combustion mode for diesel engines. One of the significant limitations of RCCI is its higher unburned hydrocarbon (HC) and carbon monoxide (CO) emissions compared to conventional diesel combustion. After-treatment control of HC and CO emissions is difficult to achieve in RCCI because of lower exhaust gas temperatures associated with the low-temperature combustion (LTC) mode of operation. The present study involves combined experimental and computational fluid dynamic (CFD) investigations to develop the most effective HC and CO control strategy for RCCI. A production light-duty diesel engine is modified to run in RCCI mode by introducing electronic port fuel injection with the replacement of mechanical injectors by the CRDI system. Experimental data were obtained using diesel as HRF (High reactive fuel) and gasoline as LRF (low reactive fuel).

This study employs TRIZ, the Theory of Inventive Problem Solving, to optimize a 2.2-liter automotive diesel engine facing challenges from system technology upgrades in the fuel injection system. This system requires the common rail pump. Two pumps were chosen and based on fuel quantity balance (QB) and drive ratio, one pump was finalized as the technical option, and it was studied in a detailed manner to identify the improving and worsening parameters with the help of a contradiction matrix and the 40 TRIZ principle, which are the main core ideas of TRIZ. The worsening parameters (drive torque) are reduced by 21.36%, and the chain load in the 0.5% worn chain condition also fulfills the system requirement. The chosen pump is further studied. This also helped to identify and categorize the system components of the main engineering system into subsystems and supersystems.

Leaf Springs are commonly used as a suspension in heavy commercial vehicles for higher load carrying capacity. The leaf springs connect the vehicle body with road profile through the axle & tire assembly. It provides the relative motion between the vehicle body and road profile to improve the ride & handling performance. The leaf springs are designed to provide linear stiffness and uniform strength characteristics throughout its travel. Leaf springs are generally subjected to dynamic loads which are induced due to different road profiles & driving patterns. Leaf spring design should be robust as any failure in leaf springs will put vehicle safety at risk and cost the vehicle manufacturer their reputation. The design of a leaf spring based on conventional methods predicts the higher stress levels at the leaf spring center clamp location and stress levels gradually reduce from the center to free ends of the leaf spring.

Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.

As a car OEM, we continuously strive to set the bar for competitors with every product. Consumer travel experiences are enhanced by increasing passenger cabin silence. There is only one steering system opening in the firewall panel, which is used for allowing intermediate shaft's fitment on the pinion shaft of the steering gear. The steering grommet is the sole component that covers the firewall cut-out without disrupting steering operations, which has a substantial impact on the NVH performance of the vehicle. It is typically used in cars to eliminate engine noise and dust entering to passenger compartment. The part is assembled inside the vehicle where the steering intermediate shaft passing through BIW firewall panel. We use a bearing, plastic bush, or direct rubber interference design in the steering grommet to accommodate the rotational input the driver provides to turn the automobile.

As we all know, automotive headliners are an essential component of any car’s interior as they cover all the internal components and provide a clean and finished look. Headliners not only increase the aesthetic appeal of a car’s interior, but also acts as an insulation and sound absorption source. As per the latest Government norms, Curtain Airbag (henceforth called as CAB) has been made mandatory and this change calls for the corresponding changes in the Headliner packaging of all passenger vehicles. In general, curtain air-bag deployment calls for a twist open of Headliner at lateral sides (a portion below Hinge-line) during the deployment. This enables the inflated airbag to flow inside the passenger cabin to protect the passenger from any injury. Conventionally no components are packaged below the hinge-line area of headliner to avoid obstruction for CAB deployment and any part fly-off concerns.

Restraint systems in automotives are inevitable for the safety of passengers. Seat belts are one such restraint system in automotives that prevent drivers and passengers from being injured during a crash by restraining them back. Seatbelt on automotives has interface with Body-in-white (henceforth called as BIW) and Trim parts in-order to serve its purpose at vehicle level. One such interface part of seat belt is the web guide, which assists and ensures the nylon web’s smooth motion at different seat track positions. Web-guides on automotives ensure the flawless motion of seat belt web at pillar trim areas. In this paper, we are discussing alternate ways of assisting the seat belt web without the web-guide as a separate part. In-order to assist and ensure the motion of nylon web in its trajectory, we have extended the flange of the pillar trim involved.

The increasing demand for higher specific power, fuel economy, Operating Costs as well as meeting global emission norms have become the driving factors of today’s product development in the automotive market. Substitution of high-density materials and more precise adjustment of material parameters help in significant weight decrease, but it is accompanied by undesirable cost increase and manufacturing complexity. This becomes a challenge for every automotive engineer to balance the above parameters to make a highly competitive design. This work is a part of the Design and Development of 2.2 L, 4 Cylinder TCIC Diesel Engine for a whole new vehicle platform, concentrated on automotive passenger car operation. This paper explains the selection of a suitable cylinder head gasket technology for a lightweight engine that acts as a sealing interface between the cylinder block and cylinder head.

In automotive manual transmission gearboxes, the synchronizer rings play a vital role in gear shift operations. The efficiency of the synchronizer ring depends upon the frictional surface geometry. The critical parameter is the synchronizer ring frictional surface circularity. The circularity deviation causes higher synchronizer ring wear and poor cone torque generation. With the current manufacturing methods and the thickness of the synchronizer ring, circularity improvement is a challenge. The synchronizer ring thread turned part is lapped to improve the circularity. Reduction in circularity can be improved by optimizing the lapping operation. In this work, an optimal lapping condition was developed using statistical methods. Taguchi DOE was used to analyze the different parameter combinations along with the noise parameter – different ranges of circularity variation in turning operation. This helps to find the best lapping parameter settings to improve the reduction in circularity.

The main objective of the work is to investigate the friction and wear behavior of sintered copper-based brake composite friction material with a change in the volume percentage of soft reinforcement particles namely MoS2 by pin-on-disc tribometer for medium-duty automotive applications. The composite brake friction material contains copper (Cu) as a matrix, tin (Sn) as an additive, silicon carbide (SiC) and molybdenum disulfide (MoS2) as hard and soft reinforcement particles and barium sulfate (BaSO4) as filler. These hybrids copper-based brake composite friction (pin) samples are successfully prepared by a change in compositions of MoS2 from 0 to 5 vol. % in the step of 1 vol. % and the characterizations of friction samples are studied to understand the physical and mechanical properties such as density, hardness, and compressive strength.

The brass synchronizers are not resistant to abusive conditions of gearbox operations, but they are very durable and cheap when used on their favorable material property working limit. The main failure which can occur in the gearbox due to the synchronizer is crash noise. During gear shifting the gear crash will create high discomfort for the driver and must apply high force to change the gears. The main factors which contribute to the crash phenomenon are the insufficient coefficient of friction, high drag in the system, and high wear rate of the synchronizer rings before the intended design life of the synchronizer. The brass synchronizers were tested on the SSP-180, ZF synchronizer test rig to know the effect of the synchronizer performance parameters like the coefficient of friction, sleeve force, slipping time as well as durability parameters like wear rate when the operating temperature of the oil is changed.

In manual transmission, the vital function of synchronizer pack is to synchronize the speed of the target gear for smooth gear shifting. The synchronizer pack consists of various elements and each of these elements has specific function. These elements are baulk rings, shifter sleeve, hub, synchro key, synchro springs etc. The function of synchronizer can be affected due to failure of any one of these elements. This work focuses on the failure of synchronizer pack due to synchro spring failure. The function of synchronizer spring is to exert the required force, to index the synchronizer ring before the movement of shifter sleeve over synchronizer ring. During the shifting of shifter sleeve from one gear to another gear, the springs deflect in both shifting directions. This causes fatigue failure of synchronizer springs. The manufacturing variations, and part quality issues results in very early fatigue failure of synchronizer springs.

Almost one-third of the fuel energy is wasted into the atmosphere via exhaust gas from an internal combustion engine. Despite several advancements in waste heat recovery technology, single-cylinder engines in the market that are currently in production remain naturally aspirated without any waste heat recovery techniques. Turbocharging is one of the best waste heat recovery techniques. However, a standard turbocharger cannot be employed in the single-cylinder engine due to technical challenges such as pulsated flow conditions at the exhaust, phase lag in the intake and exhaust valve opening. Of late, the emphasis on reducing exhaust emissions has been a primary focus for any internal combustion engine manufacturer, with the onset of stricter emission norms. Thus, the engine designer must prioritize emission reduction without compromising engine performance.

Tensile Testing is one of the most used and highly reliable method of mechanical testing to evaluate the tensile properties of the material. However, there is a large scope for discussing the behavior of the metals based on the direction of rolling and the tensile specimen size used for testing. This paper discusses the variation observed in the tensile values along the direction of rolling and traverse to the direction of rolling for S460MC. It also evaluates the variation observed in the values based on the various gauge lengths (GL) commonly used in testing as per international standards (80mm, 50mm and 25mm GL). It is observed that perpendicular to the direction of rolling, the Yield and Tensile strength of the material increase marginally while the Elongation percentage (%E) decreases by a small margin irrespective of the gauge length taken into consideration.

In most cases, the properties of a metal are evaluated in their as rolled condition, prior to any work hardening or bake hardening. But in the Automotive World, these steels get work hardened during the forming process and bake hardened in the paint shop. The goal of this paper is to evaluate the variations in the performance of Dual Phase (DP) steels and understand the most optimized method of testing and property generation. This method can then be used to extrapolate to real automotive components. Dual Phase Steels or DP Steels contain a mixture of Ferrite & Martensite from which they derive their name. They are a part of the advanced high strength and ultra-high strength steels steel family according to World Auto Steels. The Ferrite phase, with its iron content contributes to the material displaying an increased level of ductility whilst, the martensitic phase provides the steel with increased mechanical strength.

The Tractors are inevitable in the world due to its remarkable contribution majorly in farming process and other applications. the farming equipment needs to perform multiple applications to enhance the productivity and increased horsepower demands all-wheel drive (Refer fig. 1) or four-wheel drive option in the tractor. So, it is becoming a mandatory feature. The main objective of this study is, improving the torsional fatigue life in front axle spindle shaft by modifying the spline design and optimizing induction hardening heat treatment process in such a way that the other part of the system will have a minor or no design change. It helps us to reduce the part count variability, lower manufacturing cost and development time.

The global automotive industry is growing rapidly in recent years and the market competition has increased drastically. There is a high demand for passenger car segment vehicles with high torque delivery and fuel economy for a pleasant drivability experience. Also, to meet the more stringent emission requirements, automakers are trying very hard to reduce the overall vehicle gross weight. In lowering both fuel consumption and CO2 generation, serious efforts have been made to reduce the overall engine weight. An engine cylinder block is generally considered to be the heaviest part within a complete engine and block alone accounts for 3-4% of the total weight of the average vehicle, thus playing a key role in weight reduction consideration. Aluminum casting alloys as a substitute for the traditional cast iron can mean a reduction in engine block weight between 40 and 55% [9], even if the lower strength of aluminum compared to grey cast iron is considered.

The property of methanol to surface ignite can be exploited to use it in a diesel engine even though its cetane number is very low. Poor lubricity of methanol is still an issue and special additives are needed in order to safeguard the injection system components. In this work a common rail three cylinder, turbocharged diesel engine was run in the glow plug based hot surface ignition mode under different injection strategies with methanol as the main fuel in a blend with n-butanol. n-Butanol was used mainly to enhance the viscosity and lubricity of the blend. The focus was on the effect of different injection strategies. Initially three blends with methanol to n-butanol mass ratios of 60:40, 70:30 and 80:20 were evaluated experimentally with single pulse fuel injection. Subsequently the selected blend of 70:30 was injected as two pulses (with almost equal mass shares) with the gap between them and their timing being varied.

The major area in which the automotive manufacturers are working is to produce high-performance vehicles with lighter weight, higher fuel economy and lower emissions. In this regard, hollow camshafts are widely used in modern diesel and gasoline engines due to their inherent advantages of less rotational inertia, less friction, less weight and better design flexibility. However, the dynamic loads of chain system, valve train and fuel injection pump (if applicable) makes it challenging to design over-head hollow camshafts with the required factor of safety (FOS). In the present work, high-fidelity FE model of a hollow camshaft assembly is simulated to evaluate the structural performance for assembly loads, valve train operating loads, fuel injection pump loads and chain system loads. The investigation is carried out in a high power-density (70 kW/lit) 4-cylinder in-line diesel engine.

In order to sustain in automobile industry, fuel economy and robustness are playing vital role in vehicle. Every gram of weight will have an impact on fuel economy, thus burning a hole in consumers pocket and contributing heavily to the carbon footprint. Composite material development plays important role in meeting the stringent self-imposed targets of the automotive manufacturers and light weighting is becoming a prime option for improving Fuel Economy. The main objective of this paper is to optimize the weight of the luggage lid floor and reduce its cost without compromising on the strength by changing the raw material and manufacturing process. This part is in trunk compartment of the vehicle. Main function of this part is to withstand the luggage load under various user loading patterns at varied temperature and while driving on different road conditions.