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Most of the energy consumed in today's mobility industry is derived from fossil fuels. The demand for clean, renewable and affordable alternative energy is forcing the automotive industry to look beyond the conventional fossil fuels. Fuels options like liquefied petroleum gas (LPG), compressed natural gas (CNG) and ethanol blends are quickly finding widespread acceptance as alternative sources. This paper presents the results of experimental studies conducted on a 1.2-liter MPI engine with three different alternate fuels. The fuels considered for the evaluation (apart from base gasoline) are 10% ethanol-blended fuel (E10), LPG (gaseous propane: butane mix) and CNG (gaseous methane). Experiments were conducted to compare their effect on engine performance and emissions. The test results show that E10 has the lowest power drop whereas CNG has the highest power drop (12%) as compared to gasoline. The maximum power drop in LPG is 4%, which is close to the theoretical predictions.

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.

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.

Automotive OEMs are launching multiple products with ever reducing development time, balancing costs, quality and time to market, with clear focus on performance and weight. Platform architecture concepts, modular designs for differentiation etc. are strategies adopted by automotive OEMs towards shorter development cycles. Thus, concept generation phase of the digital product development process is expected to enable generation and evaluation of multiple concept architectures, carry out performance studies and largely focus on optimization, upfront. This Front loading of engineering and call for simultaneous engineering requires support in terms of quick and good CAD modeling with maturity. This paper proposes a process that focuses on generation and evaluation of multiple concepts, besides enabling optimization of concept before the detailed design phase kicks in.

As the vehicle functions are getting distributed over multiple ECUs in order to realize various complex control functions, the need for sophisticated on-board diagnostic strategies are increasing in automotive domain, leading to a significant amount of hardware and software implementations for fault management inside various ECUs in the vehicle. This paper proposes optimized vehicle level approach for fault management strategies, wherein a centralized intelligent Gateway Module is proposed in the vehicle network architecture, which will be responsible for fault management of the complete vehicle in a chronological sequence. This Gateway Module will thereby have the possibility to group a cluster of faults raised by different ECUs and correlate them meaningfully to guide the operator towards root cause of the fault.

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.

Design of a Cabin Tilting System of heavy trucks, a multi degree of freedom mechanism, is a challenge. Factors like adequate tilting angle, cabin styling, packaging, non interference of tilting system with ride comfort, forces in the system, specifications of the hydraulic system, are all very important for designing the system. Numerous considerations make the design process highly iterative hence longer design time. This paper primarily focuses on Kinematics and Dynamic analysis of the system in ADAMS and validation of system with real time testing results. Intention of this work is to make a parametric ADAMS model and link it to a Knowledge Based Engineering application to facilitate designer to quickly carry out design iterations for reducing development time. The Knowledge Based Engineering software is made using object oriented language called ‘Object Definition Language’ which has been developed using C and C++ software languages.

EU directive 2005/64/EC on type approval of motor vehicles with respect to their Reusability, Recyclability and Recoverability ( RRR ) requires vehicle manufacturers to put in place the necessary arrangements and procedures for Parts, Materials and Weight (PMW ) data collection from full chain of supply. This is required to perform the calculations of recyclability rate and recoverability rate in line with ISO 22628. Commonly practiced data collection methodologies included spreadsheet and use of internationally available IT support system for collection of material data. Data complexity and prohibitive cost for using Internationally available IT Support systems like IMDS (International Material Data System) has led to the in-house development of IT enabled Solution customizing Siemens PLM software product (Team centre Enterprise) and SAP (SRM suite).

Important vehicle performance parameters such as, fuel economy and high speed stability are directly influenced by its aerodynamic drag and lift. Wind tunnel testing to asses these parameters requires heavy investment especially when test wind tunnel is not available in the country where vehicle development center is present. Hence to save cost and to compress development time, it is essential to asses and optimize parameters of a vehicle in very early stages of development. Using numerical flow simulations optimization runs can be carried out digitally. Industry demands prediction of aerodynamic drag and lift coefficients (CD,CL) within an accuracy of a few counts, consuming minimal HPC resources and in a short turnaround time. Different OEMs deploy different testing methods and different softwares for numerical simulations.

Liquefied Petroleum Gas (LPG)-powered vehicles use a pressure regulator/vaporizer to expand and modulate the gas pressure to meet the engine's operational demands. This expansion process is accompanied by a phase change wherein liquid LPG is converted to its gaseous form. This consequently reduces the temperature of the working fluid which may result in freezing (Joule-Thompson effect). In order to aid complete phase change and avoid any freezing, the vaporizer is heated either electrically or by the engine coolant circulation. Any inefficiency in the heating may lead to improper phase change and can result in a phenomenon known as "liquid carryover," wherein a liquid LPG gets entrained in the downstream gas circuit where the gaseous form is demanded. The liquid carryover (if any) leads to the improper engine functioning leading to driveability and emission issues.

The power output of an internal combustion engine is directly proportional to the amount of air that can be forced into the cylinder per cycle and the amount of fuel that can be burned efficiently. The amount of air is most effectively increased by means of a mechanical supercharger. The purpose of this paper is attempting the non mechanical supercharging ways (Supercharging by means of gas dynamic effects) for naturally aspirated (NA) diesel engines and understanding in a better way the induction gas dynamics and its influence on engine performance characteristics. Wave dynamics in the intake system has strong influence on the performance of naturally aspirated internal combustion (IC) engines. This paper presents an application of Helmholtz resonator in the induction system of the naturally aspirated diesel engine to improve the engine breathing efficiency (volumetric efficiency).

New noise regulations, with reduced noise limits, have been proposed by UN-ECE. A new method which aims at representing urban driving of the vehicles more closely on roads is proposed and is considerably different from the existing one (IS 3028:1998). It is more complex; we also found that some of the low powered vehicles can not be tested as per this method. The paper proposes ways of improvement in the test method. The new noise reduction policy options will have a considerable impact on compliance of many categories of vehicles. Technological challenges, before the manufacturers, to meet all performance needs of the vehicle along with the cost of development will be critical to meet the new noise limits in the proposed time frame.

Regenerative braking has become one of the major features for a hybrid vehicle as it converts brake energy into electrical energy storable into battery and leads to an increase in overall fuel efficiency of the vehicle. Traditional regenerative braking systems are designed such that the mechanical braking force from the friction brakes is varied in order to get maximum electric braking. This is the optimum method; however, such a system calls from electronics (Anti-lock Braking System) for regulation of mechanical braking leading to an increased cost. In this paper, the authors present a new strategy for implementing a regenerative brake strategy without changing the mechanical brake system of a conventional vehicle converted to a hybrid vehicle. The electric motor that serves as the traction motor or the Integrated Starter Generator (ISG) system, is used for regenerative braking also. There is no change in the other vehicle specifications as compared to the conventional vehicle.

The world today is majorly dependent upon fossil fuels for power generation, of which diesel forms an integral part. Diesel engines, having the highest thermal efficiency of any regular internal or external combustion engine, are widely used in almost all walks of life and cannot be dispensed with in the near future. However, the limited availability of diesel and the adverse effects of diesel engine emissions like nitrogen oxide (NOx) and soot particles raise serious concerns. Hence, their performance and emission improvement continues to be an avenue of great research activity. In this research work, the effects of blending Diethyl Ether with diesel in various proportions (5%, 10%, 15% and 20% by volume) were evaluated on engine performance and emissions of an industrial internal combustion engine.

1 With increasing fuel price, the power train size is on a downward trend. For Fuel Economy maximization, the engine capacity and reduction ratios are getting reduced. So gradability of a vehicle is becoming a trade off factor for the power train size finalization in a car. At the same time OEMs are working hard to maintain profitability by reducing development and operational cost and time. In this complexly competitive scenario in automobile manufacturing, simulation is gaining an upper hand over actual testing as simulation consumes lesser time and resource as compared to actual testing. This paper is aimed at developing a simulation technique for restart or stop and start gradability which is a very critical parameter for finalization of engine torque characteristics and power train configuration. The simulation is done on AVL-CRUISE software.

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.

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.

Gasoline engines with Multi point fuel injection (MPFI) technology are being developed with naturally aspirated and/or turbocharged engines. Wherein a MPFI and turbo charged combination engines have certain challenges during development stages. One of the important challenge is design of air intake and exhaust system. With MPFI turbocharged engine combination, the under bonnet heat management is crucial task for drivability. The heat management of air intake plays a vital role in drivability part therefore a design layout of air intake path is an important aspect. Drivability can be categorized as low end, mid-range and top end drivability. Turbocharged MPFI engines have a typical phenomenon of ‘Lag in response’ in the low-end region. This ‘Lag in response’ phenomenon at low-end drivability region can be overcome through optimization of air intake system and optimization of exhaust back pressure.

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.

Pneumatic brake system is widely used in heavy truck, medium and heavy buses for its great superiority and braking performance over other brake systems. Pneumatic brake system consists of various valves such as Dual Brake Valve (DBV), Quick release Valve (QRV), Relay Valve (RV), Brake chambers. Dynamics of each valve is playing a crucial role in overall dynamic performance of the braking system. However, it is very difficult to find the contribution of each valve and pipe diameters in overall braking performance. Hence, it is very difficult to arrive a best combination for targeted braking performance as it is not possible to evaluate all combination on the actual vehicle. Hence, it is very important to have a mathematical model to optimize and evaluate the overall braking performance in early design phase. The present study is focusing on the mathematical model of a pneumatic brake circuit.