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Two carburetted passenger cars of different makes, converted for CNG (Compressed Natural Gas) operation (in dual mode) and optimised by ARAI (The Automotive Research Association of India, Pune, India), were tested for vehicular performance. The respective engines were also mapped for performance, energy consumption and emission. The power loss in CNG mode was 7% & 15% and torque reduction was 21% & 15% in respective engines. There is considerable improvement in thermal efficiency and reduction of emission in the entire operating range. The vehicle performance on Chassis Dynamometer shows similar results. The second engine was also tested with a ceramic catalytic converter which gave 93% reduction in CO and 50% reduction in HC in major portion of operating range. 1100 CC car was also tested on the test track. Optimisation work included installation of ARAI mixer design.

Diesel powered electric generators are used in a variety of applications, such as emergency back-up power, temporary primary power at industrial facilities, etc. As regulatory and customer requirements demand quieter designs, special attention is given to the design of acoustic enclosures to balance the need of noise control with other performance criteria like ventilation and physical protection. In the present work, Statistical Energy Analysis (SEA) approach augmented by experimental inputs is used to carry out Vibro-acoustic analysis of an enclosure for higher capacity Diesel generator set. The exterior sound radiated from an enclosed generator is predicted and further enclosure is optimized for an improved sound-suppression. The airborne sources such as engine, alternator, radiator fan and exhaust are modelled explicitly using experimental noise source characterization. Structure borne inputs are also captured in the test for improving modelling accuracy.

Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.

Due to the transformation of the automotive industry from conventional vehicles to electric vehicles, new challenges have emerged concerning Electromagnetic Compatibility. Though the Radiated Emission limits in global regulation are the same for both types of powertrains of vehicles, however, due to the phenomena of conversion of high voltage to low voltage, rapid charging/discharging, and different components involved in electric powertrain, the Radiated Emission from electric vehicles give a strikingly different trend which is challenging to combat. When compared with the conventional Spark Ignition vehicle, many other electronic components of the electric vehicle stay in the mode of Power ON while in the “Ignition ON” steady state. This resulted in us observing a significant shift in the amplitude and frequency throughout the frequency band of Radiated Emission measurement.

Following global trends of increasingly stringent greenhouse gas (GHG) and criteria pollutant regulations, India will likely introduce within the next decade equivalent Bharat Stage (BS) regulations for Diesel engines requiring simultaneous reduction in CO2 emissions and up to 90% reduction in NOx emission from current BS-VI levels. Consequently, automakers are likely to face tremendous challenges in meeting such emission reduction requirements while maintaining performance and vehicle total cost of ownership (TCO), especially in the Indian market, which has experienced significant tightening of emission regulation during the past decade. Therefore, it is conceivable that cost effective approaches for improving existing diesel engines platforms for future regulations would be of high strategic importance for automakers.

Currently, on-road transport contributes nearly 12% of India’s total energy related carbon dioxide (CO2) emissions that are expected to be doubled by 2040. Following the global trends of increasingly stringent greenhouse gas emissions (GHG) and criteria emissions, India will likely impose equivalent Bharat Stage (BS) regulations mandating simultaneous reduction in CO2 emissions and nearly 90% lower nitrogen oxides (NOx) from the current BS-VI levels. Consequently, Indian automakers would likely face tremendous challenges in meeting such emission reduction requirements while balancing performance and the total cost of ownership (TCO) trade-offs. Therefore, it is conceivable that cost-effective system improvements for the existing internal combustion engine (ICE) powertrains would be of high strategic importance for the automakers.

This work is a part of program on “Development of High Performance DI, 3 Cylinder CRDI Diesel Engine to meet Euro-IV/V Emission Norms focused on automotive passenger car application purpose. This is a 3 Cylinder, TCIC engine designed for combustion pressure of 160 bar max for first stage which is being upgraded to 200 bar max in the second stage. Cylinder Head design is a part of complicated configuration whose construction and principal dimensions are dependent on the size of inlet and exhaust valves, fuel injectors positioning and mounting, port layout and swirl and shape of combustion chambers. The cylinder head of a direct-injection diesel engine has to perform many functions. It has to bring charge air to the cylinder and exhaust gas from the cylinder, with minimum pumping loss and required swirl and other properties of charge motion.

To meet the latest trends in internal combustion engines pertaining efficiency, emissions and durability, downsizing of the engine has become the key focus area. This paper describes about a robust, reliable and an integrated approach used in design and development of state of art high power density/ high speed engine developed from the concept, which can be adopted for passenger car and LCV application. A three-cylinder, 1.5 liter displacement diesel engine, fully balanced is being designed with an objective to produce 115kW @ 4200 rpm, delivering a specific power output over 75 kW/liter, which is at par with a contemporary class of specification in it. In the first stage, a derated version of 75 kW (50 kW/liter) with Euro-IV and Euro-V specifications is targeted aiming at smaller car and light motor vehicle segment and a prime-mover for hybrid application.

This work is a part of program on “Development of High Power Density DI, Diesel Engine to Meet US EPA - Tier III Emission norms for off highway and Genset application purpose. This is a 4 Cylinder, TCIC engine delivering 165 Hp @ 2500 rpm. BMEP at max torque comes to be 18 bar giving max cylinder firing pressure of 160 bar. Engine block is a most vital component which has to serve various functions all together. Also design of block for such a high BMEP levels, demands to give a different design strategy required for development of High Performance Engines. In order to reduce overall production cost, several constraints are imposed on design of new block. Design of block is carried out within several design, assembly and manufacturing constraints such as maintain a specific cylinder centre distance, integral oil cooler in the engine block, re-location of camshaft and FIE positions, incorporation of various accessories viz. steering pump, Air Compressor etc.

A methodology for design and development of radiator cooling fan is developed with an objective to improve underhood thermal management. For this purpose an Axial Fan Design Software has been developed which is based on Arbitrary Vortex Flow theory. The software is useful for obtaining initial blade design for the given basic functional requirements in terms of Airflow, Pressure Rise and Speed which defines the operating point of the fan. CFD analysis of the initial fan design is then carried out to predict the fan performance curve. Computation model resembles a fan set up in a wind tunnel. Further, Parametric Optimization is carried out using CFD to meet the functional requirements. A Rapid Prototype sample of the optimized fan design is manufactured and tested in a fan test rig made as per AMCA 210-99 standard to evaluate the fan performance curve and the power consumption.

The Exhaust Noise is one of the major noise pollutants. It is well-known that for higher noise reduction, the engine has to bear high back pressure. For a race car, back-pressure plays a major role in engine's performance characteristics. For a given condition of engine rpm & load, conventional muffler has a fixed value of back-pressure and noise attenuation. Better acceleration requires low back-pressure, but the exhaust noise should also be less than the required (Norm) value (110 dBA). This contradicting condition is achieved here by using a ‘Butterfly Valve’ in this novel exhaust muffler. The butterfly valve assumes 2 positions i.e. fully open & fully closed. When the valve is fully closed, the noise reduction will be higher, but the back-pressure will also shoot up. When open, noise reduction will be less and so the back-pressure. So, when better performance is required, the valve is opened and back-pressure is reduced. The muffler is designed for a 4 cylinder 600 cc engine.

The use of Hybrid Electric Vehicles (HEV) will become imperative to meet the emission challenges. HEV have two power sources-fossil fuels driven I.C. Engine and the battery based drive. Battery technologies have seen a tremendous development, and therefore HEV’s have been benefited. Even as the battery capacities have improved, maintaining and monitoring their health has been a challenge. This research paper uses open-source platform to build a BMS. The flexibility in the implementation of the system has helped in the rapid prototyping of the system. The BMS system was evaluated on a scaled-down electric toy car for its performance and sustainability. The BMS was evaluated for reverse polarity, protection against overcharge, short-circuit, deep discharge and overload on lead acid battery. It also includes temperature monitoring of the batteries. This proposed system is evaluated on the in-house HEV two-wheeler. The initial results are promising.

Gerotor pump is a positive displacement pump unit which is widely used for lubrication in on-road and off-road engine applications. This paper is focused on Gerotor pump design competency established at ARAI comprising of design of inner and outer rotors, suction & delivery ports, optimizing inlet and outlet diameters & its position, development of methodology to calculate oil flow rate, volumetric efficiency, mechanical efficiency & slippage. The finalization of design is followed by CFD of Gerotor pump to optimize the pressure and flow pulsation. A trochoidal profile is used to design the inner and outer rotors and its conjugate profile are realized by a set of equations using a method based on the theory of gearing. Suction and delivery port is analytically designed based on the same design parameters of the trochoidal profile.

Automotive clutches form the most important component in the drive line which acts both as torque transmitter and as a fuse. Testing clutches, in the vehicle assembly, poses certain limitations. In this context the automotive clutch, as a component, needs to be evaluated to determine various performance parameters like wear, load loss, slipping torque, slipping time etc. to meet desired design, performance and durability requirements. It is very important to simulate engine and vehicle conditions in terms of operating environment, speed and load accurately while evaluating above parameters. This creates lot of challenges to design and develop a test rig capable of evaluating complete clutch performance. Very limited options are available for such test rigs worldwide. In India, no manufacturer provides such indigenous test rigs. Developing an indigenous, cost effective clutch test rig was the need of the hour.

The Indian automotive industry is striving towards more safe and durable vehicles. A need was felt to study the effect of changes in axle static loads on fatigue life of the axle components. Also, there was a need to develop generic test method, as there are no test standards or generic methods available in public domain for fatigue testing of commercial vehicle axles. The study was carried out to check direct effect of change in axle loads on various connections on axle, effect of suspension configuration and force distribution, Vehicle dynamics, etc. In this paper, an India specific generic load spectra was evaluated for accelerated laboratory validation. Paper discusses the methodology as; study of heavy commercial vehicle systems, road load data collection on identified test vehicles w.r.t. test matrix finalized, India specific test loads and load spectra development, normalization of axle load spectra w.r.t to static axle weights and arriving at test guidelines.

Engine mount is an integral part of any Internal Combustion engine. It is the medium which isolates the vibrations coming from engine being transferred to the chassis or body. Engine or power plant is the main source of unbalanced vibrations. The major role of an engine mount is to reduce those vibration levels, improve ride comfort and increase the life of an engine and its parts [1]. This work determines the Test methodology development for passenger car engine mounts in the Laboratory by using Multi-axial environment [2]. This explains the details of truly Multi-axial test rig development, Drive file creation and the Durability Testing with the maintained vehicle conditions by simulating field conditions in the laboratory. The Multi-axial test rig developed with incorporation of vehicle’s both Front Drive shafts torques and One Propeller shaft which simulates the Front wheel drives and the rear prop shaft torque.

Last decade has been era of environmental awareness. Various programs have launched for making devices and appliances eco-friendly. This initiative has lead automobile industry toward hybridization and now total electrification of vehicles. As electric motor is being added to automobile as a prime mover, due to high frequency vibrations along with higher torque electric motor needs to be isolated properly & carefully as this vibration can damage other automobile parts. Dynamic response of electric motor is different from response of IC engines, so use of engine mounting design method may not be suitable for designing mounting system for electric motor. First, both 4- point and 3- point mounting system are considered for analytical and experimental investigation of force and displacement transmissibility. Position and orientation of elastomeric mounts plays important role in design of mounting system for electric motor.

The function of the automotive transmission is to reliably transmit torque and motion between engine and wheels at acceptable levels of noise, vibration and desired life. Gear drive components most commonly subject to distress are the gears, shafts, bearings and seals. The variables in the entire power-system, such as vibration, misalignment, type of lubricant used, material properties, operating temperature and abuse are considered as the main root causes for the gear failures. The bending and contact strength of the gear tooth are considered to be one of the main contributors for the failure of the gear in a gear set. Thus, Heartzian stress analysis has become popular as an area of research on gears to minimize or to reduce the failures of gears. In this research work, one of the major field issues related to 1st gear and reverse gear pitting at very low life for 6 speed manual transmission for mining/ quarry application is studied.

Hydrogen Internal Combustion Engine (H2ICE) has hydrogen gas storage system and is operated at very low temperature before it enters the combustion chamber. The effect of hydrogen on steel materials is detrimental because of hydrogen embrittlement. Forged steel parts are used in engine specifically valve. The goal of the work is to analyze the outcome of low temperature i.e. 35 °C to -30 °C on three types of forged steel materials i.e. 40Cr4, 42CrMo4 and EN8 and assess any potential changes in their properties due to ductile to brittle transition. Charpy impact test is widely used to determine the temperature at which a material shifts from exhibiting ductile behavior to brittle behavior. This transition is critical for understanding the safety and reliability of steel components, as brittle fracture can lead to catastrophic failures.

The Indian government has been promoting electric vehicles through various policy initiatives, such as offering incentives and subsidies to EV manufacturers and consumers, establishing charging infrastructure across the country, and setting ambitious targets for EV adoption. These measures aim to reduce the dependence on imported fossil fuels, mitigate air pollution, and promote sustainable mobility. As a result, the demand for electric vehicles across India is steadily increasing, and the country is emerging as a lucrative market for EVs globally. An electronically commuted brushless DC (BLDC) motor usually functions for traction in electric two-wheelers. Electric vehicles need to comply with electromagnetic compatibility (EMC) requirements. During the EMC compliance of electric two-wheelers, it is certain that the BLDC motor and its controller play an important role.