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DFSS is a disciplined problem prevention approach which helps in achieving the most optimum design solution and provides improved and cost effective quality products. This paper presents the implementation of DFSS method to design a distinctive cooling system where engine is mounted in the rear and radiator is mounted in the front of the car. In automobile design, a rear-engine design layout places the engine at the rear of the vehicle. This layout is mainly found in small, entry level cars and light commercial vehicles chosen for three reasons - packaging, traction, and ease of manufacturing. In conventional Passenger cars, a radiator is located close to the engine for simple packaging and efficient thermal management. This paper is about designing a distinctive cooling system of a car having rear mounted engine and front mounted radiator.

Authors were challenged with a task of developing a full vehicle simulation model, with a target to simulate the electrical system performance and perform digital tests like Battery Charge Balance, in addition to the fuel efficiency estimation. A vehicle is a complicated problem or domain to model, due to the complexities of subsystems. Even more difficult task is to have a control algorithm which controls the vehicle model with the required control signals to follow the test specification. Particularly, simulating the control of a vehicle with a manual transmission is complicated due to many associated control signals (Throttle, Brake and Clutch) and interruptions like gear changes. In this paper, the development of a full vehicle model aimed at the assessment of electrical system performance of the vehicle is discussed in brief.

Reduction of NOx (Oxides of Nitrogen) and particulates from engine exhaust is one of the prime considerations in current research and development in automotive industry. The present paper describes the combustion optimization done on a four cylinder, 4 liter DI diesel engine to meet stringent Euro-III emission norms. The engine FIE (Fuel Injection Equipment) and injector geometry was optimized for performance and emission. Smoke measurements were considered as indicative of soot, to predict particulate emissions. This was done to simplify the overall process and save development time. It was concluded that by combining the flexibility of electronically controlled fuel injection begin, with improved nozzle technologies, with higher spray velocities and spray penetration, a considerable reduction in NOx and particulate emissions can be achieved. This can serve as a low cost solution, without any exhaust after-treatment systems.

Micro Hybrid Systems are a premier approach for improving fuel efficiency and reducing emissions, by improving the efficiency of electrical energy generation, storage, distribution and consumption, yet with lower costs associated with development and implementation. However, significant efforts are required while implementing micro hybrid systems, arising out of components like Intelligent Battery Sensor (IBS). IBS provides battery measurements and battery status, and in addition mission critical diagnostic data on a communication line to micro hybrid controller. However, this set of data from IBS is not available instantly after its initialization, as it enters into a lengthy learning phase, where it learns the battery parameters, before it gives the required data on the communication line. This learning period spans from 3 to 8 hours, until the IBS is fully functional and is capable of supporting the system functionalities.

Now a day’s automated manual transmissions (AMT) are getting popular because of hassle-free gear shifting and improved fuel economy. OEMs are converting their existing manual gearbox to AMT gearbox with solution like hydraulic or electric AMT kit that replaces the manual shift mechanism to automated actuators. Generally, in manual gearbox, the operational principal of reverse gear is sliding mesh. Due to sliding mesh gear arrangement, it can create interruption for gearshift while controlling shift actuators. In this paper, reverse gear shift arrangement and its operational dynamics at different operating condition has been studied and analyzed in detail. Based on status of vehicle, to ease the gearshift, engagement flow process proposed. The control methods that increases probability of smooth and easier shifting in all operating condition discussed in detail. The developed control algorithm discussed along with its implementation on real vehicle and results.

Engine Stop/Start System (ESS) promises to reduce greenhouse emissions and improve fuel economy of vehicles. Previous work of the Authors was concentrated on bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, actual benefits of ESS are reduced. A modified control algorithm was proposed and proven for the local driving conditions in India. The ways in which a given driver behaves on the controls of the vehicles like Clutch and Brake Pedals, Gear Shift Lever were not uniform across the demography of study and varied significantly.

With the current state of ever rising fuel prices and unavailability of affordable alternate technologies, significant research and development efforts have been invested in recent times towards improving fuel efficiency of vehicles powered with conventional internal combustion engines. To achieve this, a varied approach has been adopted by researchers to cover the entire energy chain including fuel quality, combustion quality, power generation efficiency, down-sizing, power consumption efficiency, etc. Apart from energy generation, distribution and consumption, another domain that has been subjected to significant scrutiny is energy recuperation or recovery. A moving vehicle and a running engine provide a number of opportunities for useful back-recovery and storage of energy. The most significant sources for recuperation are the kinetic energy of the moving vehicle or running engine and to a lesser extent the thermal energy from medium such as exhaust gas.

When an automobile negotiates a flooded region, water is splashed due to the rotational motion of the wheels. This water enters the air intake system of the turbocharged intercooled engine along with air and can pass through the turbocharger, intercooler and enter the engine. As water is an incompressible fluid, the piston cannot compress water inside the cylinder which leads to connecting rod bending and severe engine damage. This paper explains how the same has been resolved using CFD methodology and proposes the re-designed model of mud cover as a solution to this problem. The entire process has been streamlined and major time and cost reduction achieved by using simulation for optimization. The simulated results have been validated by extensive trials for correlation and outdoor tests for durability. Same analysis technique is used as a template to modify the air intake system.

Key on/off (KOKO) Vibration plays a vital role in the quality of NVH (Noise Vibration and Harshness) on a vehicle. A good KOKO experience on the vehicle is desirable for every customer. The vibration transfer to the vehicle can be refined either by reducing the source vibrations or improving isolation efficiency. For the engine mounting system of passenger cars, the mounts are an isolating element between the powertrain and receiver. Various noise, Vibration, and harshness criteria must be fulfilled by mounting system performance like driver seat rail vibration (DSR), tip-in/tip-out, judder performance, DSR at idle and Key on/off Vibration. Out of these requirements, in the paper, the investigation is done on KOKO improvement without affecting other NVH parameters related to mount performance. Higher damping is required to isolate Vibration generated during the Key-on event, and lower damping is required during the idle condition of the vehicle.

Better ride and comfort, enhanced safety, reliability and durability, lower running cost as well as cost of ownership continue to be challenges for automotive OEMs. Higher fuel efficiency is considered as USP not only for lower running cost but also is hygiene factor from sustainability point of view. This has necessitated the need for Augmenting Light weighting horizon in automotive OEMs. Augmenting this leads to invention of innovative materials and processes for emerging cost competitive market. This paper focuses on technology efforts towards augmenting light weighting Horizon in Automotive. Light weighting concepts being explored by OEMs with the help of automotive component manufacturers from Powertrain - Engines & Transmission, Chassis and Suspension are discussed.

Vehicle incab booming perception, a low frequency response of the structure to the various excitations presents a challenging task for the NVH engineers. The excitation to the structure causing boom can either be power train induced, depending upon the number of cylinders or the road inputs, while transfer paths for the excitation is mainly through the power train mounts or the suspension attachments to the body. The body responds to those input excitations by virtue of the dynamic behavior mainly governed by its modal characteristics. This paper explains in detail an integrated approach, of both experimental and numerical techniques devised to investigate the mechanism for boom noise generation. It is therefore important, to understand the modal behavior of the structure. The modal characteristics from the structural modal test enable to locate the natural frequencies and mode shapes of the body, which are likely to get excited due to the operating excitations.

Climate change due to global warming calls for more fuel-efficient technologies. Parallel Full hybrids are one of the promising technologies to curb the climate change by reducing CO2 emissions significantly. Different parallel hybrid electric vehicle (HEV) architectures such as P0, P1, P2, P3 and P4 are adopted based on different parameters like fuel economy, drivability, performance, packaging, comfort and total cost of ownership of the vehicle. It is a great challenge to select right hybrid architecture for different vehicle segments. This paper compares P2 and P3 HEV with AMT transmission to evaluate most optimized architecture based on vehicle segment. Vehicles selected for study are from popular vehicle segments in India with AMT transmission i.e. Entry segment hatch and Compact SUV. HEV P2 and P3 architectures are simulated and studied with different vehicle segments for fuel economy, performance, drivability and TCO.

IC (Internal Combustion) engines are evolved and refined over time to greater levels of technology in terms of emission, performance, NVH (Noise, Vibration & Harshness), and design philosophy. Crank-train generates a greater impact on NVH optimization due to its geometry and dynamics. Hence, more attention to mass balancing is required to minimize the negative impact on NVH. The present work demonstrates the evaluation of balancing rate of crank-train system from the first principle of couple balancing. Calculations are conducted at the concept stage to estimate an internal rotating couple balancing of crank-train system due to counterweights and rotating masses. As crankshaft weighs approximately 10-12% weight of an engine and its counter weight plays a vital role in balancing, its optimization will result in a significant impact on NVH.

The goal of reducing fuel consumption and CO2-Emission is leading to turbo-charged combustion engines that deliver high torque at low speeds (down speeding). To meet NVH requirements damper technologies such as DMF (Dual Mass Flywheel) are established, leading to reduced space for the clutch system. Specific measures need to be considered if switching over from SMF (Single Mass Flywheel) to DMF [8]. Doing so has an impact on thermal behavior of the clutch system, for example due to reduced and different distribution of thermal masses and heat transfer to the surroundings. Taking these trends into account, clutch systems within vehicle powertrains are facing challenges to meet requirements e.g. clutch life, cost targets and space limitation. The clutch development process must also ensure delivery of a clutch system that meets requirements taking boundary conditions such as load cycles and driver behavior into account.

This paper deals with the problem of cyclic irregularities during idling in relation with port to port fuel delivery variation of rotary Fuel Injection Pump (FIP) for a diesel engine. The relation is demonstrated on a two cylinder engine, where problem of high cyclic irregularities was observed for which the root cause was identified as the fuel delivery variation from the FIP, which was later taken up for the improvements in the design. This paper discusses the technical approach used in identifying the root cause for the high cyclic irregularities and the solution of the problem. It is demonstrated how angular acceleration of the crankshaft free end can be used to diagnose the non-uniformity of combustion in different cylinders which leads to higher cyclic irregularities. The solution discusses the improvements done in the hydraulic passages of the head and rotor of the FIP for line to line fuel delivery variation control.

Optimization of vehicle engine cooling package with requisite heat rejection capacity plays a key role in achieving most fuel economy and also in meeting the stringent noise norms. A set of design and operating features from existing vehicle engine cooling systems is reviewed and evaluated for their potential to provide optimized engine cooling. The features reviewed states significant potential in engine performance but these are balanced by satisfying required engine cooling requirement. Sets of trials are carried out on said vehicle with dissimilar features of cooling packages and the results are evaluated. Fuel economy trials in performance mode are carried out on vehicle with well thought-out cooling package for healthier comparison.

Air intake system (AIS) plays a major role in reducing the noise level in passenger car compartment, which has become an important requirement due to increasing customer expectation for better in cab noise. The ideal air intake system design should have minimum possible noise at snorkel entry point which ultimately contributes in cabin noise. There are different techniques that are implemented for an air intake system noise reduction e.g. choosing proper location of air entry suction point in engine bay compartment, suitable design for air filter box (volume), duct designs etc. Further design improvement are possible with an addition of tuned resonators in the system. An addition of resonator have major effect seen in reducing air induction noise and to meet target Sound Pressure Levels (SPL). But at the same time, selecting the correct type of resonator, its position & volume, frequency/s band at which resonator is tuned are important parameters.

The modern trend of engine downsizing for CO₂ reduction coupled with stringent emission norms compel the engine air inlet system to outperform the conventional designs. Modern turbo diesel engine air inlet system handles higher & higher air flow, boost pressure and temperature. Air inlet system ducting designs have become complex due to oil particles (received through PCV system), engine movement and isolation for NVH. Air inlet ducting failures; like oil mist leakage through joints and seepage through hose wall cause high engine oil consumption and most predominantly environment damage. Also to some extent boost leakage in certain operating conditions. These failures reduce the reliability and performance of engine in certain conditions. This paper discusses design and development of cost-effective non-permeable and leak-proof hose-piping system for turbocharged diesel engine where PCV system was connected to air inlet system.

Fuel cell electric vehicles generally have two power sources – the fuel cell power system and a high voltage battery pack - to power the vehicle operations. The fuel cell power system is the main source of power for the vehicle and its operations are supported by the battery pack. The battery pack helps to tackle the dynamic power demands from the vehicle such as during acceleration, to which the response of the fuel cell might be slower. The battery is also used to recover the energy from regeneration during braking and can also be used to extend the range of the vehicle in case the storage tanks runs out of hydrogen. In order to maximize the fuel efficiency of the fuel cell power system it is critical that these two power sources are used in conjunction with each other in an optimal manner.

Fuel efficiency is one of the most important customer requirement in Indian market as well as very crucial to meet the upcoming regulation like CAFÉ for Indian Automotive manufacturers. Most of the technology changes to meet this challenge, always come with a cost penalty with hardware addition. To counter the above challenge, a strategy has been identified in the EMS software that will dynamically adapt the spark timing based on fuel octane rating. This strategy has resulted in fuel efficiency improvement on Modified Indian Drive Cycle on chassis dynamometer test and as well as on real life road tests using fuels with various octane number.