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Ride is considered to be one of the crucial criterion for evaluating the performance of a vehicle. Automobile industry is striving for improvement in designs to provide superior passenger comfort in Commercial vehicles segment. In Industry, Quarter-car model has been used for years to study the vehicle’s ride dynamics. But due to lower DOF involved in quarter car, the output accuracy is somewhat compromised. This paper aims in development of a 7 DOF full-car Model to perform the ride- comfort analysis for Light Duty 4*2 Commercial Bus using MATLAB Simulink which can be used to tune the suspension design to meet the required ride-comfort criteria. Firstly, experimental data and Physical Parameters are collected by performing Practical Test on commercial Bus on different road profiles. Secondly, a Full Car Mathematical Model with 7 DOF has been developed for a bus using MATLAB Simulink R2018a.

Particulate matter is one of the major pollutant responsible for deteriorating air quality, particularly in urban centers. Information on contributing sources with the share from different sources is a first and one of the important steps in controlling pollution. Diverse sources, anthropogenic as well as natural, like industries, transport, domestic burning, construction, wind-blown dust, road dust contribute to particulate matter pollution. Receptor modeling is a scientific method which is utilized for assessment of the contribution of various sources based on chemical characteristics of particulate matter sources and ambient air particulate matter. Representative data of fractions of various chemical species in the particulate matter from the different sources i.e. source fingerprint is an essential input for the receptor modeling approach.

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.

To enhance the crashworthiness of electric vehicles, designing the optimized and safer battery pack is very essential. The deformed battery cell can result in catastrophic events like thermal runaway and thus it becomes crucial to study the mechanical response of battery cell. The goal of the research is to experimentally investigate the effect of mechanical deformation on Lithium-ion battery cell. The paper thoroughly studies the phenomenon of short circuiting at the time of failure. Various experiments are carried on 18650 cylindrical cells (NCA chemistry) under custom designed fume hood. The setup captures the failure modes of battery cell. The loading conditions have been designed considering the very possible physical conditions during crash event. The study has been done for radial compression, semicircular indentation, hemispherical indentation, flat circular indentation and case of three-point bending.

Design of real time active controls for structural dynamics problems requires a very precise mathematical model, to closely determine the system dynamic behavior, under virtual simulation. The finite element models can somehow be used as a mathematical model but due to complex shape/structure of the component, the size of discrete models resulting from finite element analysis is usually very large, causing the virtual simulation to be extremely computationally intensive and time consuming, also the boundary conditions applied are not very scalable, making the system deviate from its real dynamic behavior. Thus, this paper deals with the design of a Model Order Reduction technique, using orthogonal decomposition of system matrices, which can be used for creating accurate low-order dynamic model with scalable boundary conditions.

Electric Vehicles (EVs), with its inherent advantage of zero tailpipe emissions, are gaining importance because of aggressive push from government not only to reduce air pollution but also to reduce dependency of fossil fuel. EVs and necessary charging infrastructure along with ‘connected’ technology is redefining mobility. Considering the fast growing EV market, it becomes important for an EV Powertrain Architect to design and develop a powertrain solution having low engineering efforts and satisfying business, market and regulatory requirements at a competitive price. This paper presents a compact, flexible, convenient and smart featured simulation tool for an EV Powertrain Architect for estimating the specifications of key powertrain components such as traction battery and electric motor. The proposed tool takes into consideration the end-user as well as the regulatory requirements of range, maximum speed, acceleration and gradeability.

CNG has recently seen increased penetration within the automotive industry. Due to recent sanctions on diesel fuelled vehicles, manufactures have again shifted their attention to natural gas as a suitable alternative. Turbocharging of SI engines has seen widespread application due to its benefit in terms of engine downsizing and increasing engine performance [1]. This paper discusses the methodology involved in development of a multi cylinder turbocharged natural gas engine from an existing diesel engine. Various parameters such as valve timing, intake volume, runner length, etc. were studied using 1D simulation tool GT power and based on their results an optimized configuration was selected and a proto engine was built. Electronic throttle body was used to give better transient performance and emission control. Turbocharger selection and its location plays a critical role.

Major cause of air pollution in the world is due to burning of fossil fuels for transport application; around 23% GHG emissions are produced due to transport sector. Likewise, the major cause of air pollution in Indian cities is also due to transport sector. Marginal improvement in the fuel economy provide profound impact on surrounding air quality and lightweighting of vehicle mass is the key factor in improving fuel economy. The paper describes robust and integrated approach used for design and development of lightweight bus structures for Indian city bus applications. An attempt is made to demonstrate the use of environment friendly material like aluminium in development of lightweight superstrutured city buses for India. Exercise involved design, development and prototype manufacturing of 12m Low Entry and 12m Semi Low Floor (SLF) bus models.

Passive safety regulations specify minimum safety performance requirements of vehicle in terms of protecting its occupants and other road users in accident scenarios. Currently for majority cases, the compliance of vehicle design to passive safety regulations is assessed through physical testing. With increased number of products and more comprehensive passive safety requirements, the complexity of certification is getting challenged due to high cost involved in prototype parts and the market pressures for early product introduction through reduced product development timelines. One of the ways for addressing this challenge is to promote CAE based certification of vehicle designs for regulatory compliance. Since accuracy of CAE predictions have improved over a period of time, such an approach is accepted for few regulations like ECE-R 66/01, AIS069 etc which involves only loadings of the structures.

An excellent physical and mechanical property makes Aluminium (Al) alloy suitable alternative lightweight materials against steel and cast iron in automotive components. ICME is a computational tool, which integrates the materials information to engineering product performance analysis. MatCalc is ICME tool, which follows the chain rule of process, microstructure, property and performance relationship in materials development. This paper reports the development of Al 6061-T6 propeller shaft through forging process and the materials and process model of the Al yoke is simulated using MatCalc simulation software. Finite element analysis method is used for designing of Al 6061-T6 propeller shaft. The forged Al yoke is solutionized at temperature 550°C for 1 hr followed by artificial ageing at temperature 180°C for 16 hrs to improve the hardness and strength of the yoke.

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.

Two-stroke engine two- and three-wheelers comprise over half of the total vehicle population in South Asia and, as such, are likely to be significant contributors to particulate air pollution in large cities. Because there are no standards for particulate emissions from two-stroke engine gasoline vehicles, there is very little data available quantifying their emission levels. This study examined the procedure for measuring particulate emissions from two-stroke engines which comprise predominantly liquid droplets, and measured mass emissions from in-use three-wheelers to examine the impact of the engine condition, lubricant type and quantity, and fuel quality. The results are compared to smoke emission levels.

The paper discusses the methodology for measuring the sound absorption of sound package materials in a different sizes of reverberation chambers. The large reverberation chamber is based on test methods and requirements as per ASTM C423 and ISO 354 standards. Both the test standards are similar and recommend a reverberation chamber volume of at least 125 m3 and 200 m3 respectively for sound absorption measurements from 100 Hz to 5000 Hz. The test sample size requirements are from 5.5 to 6.7 m2 as per ASTM C423 and 10 to 12 m2 as per ISO 354. In the automotive sector passenger car, heavy truck, and commercial vehicle, the parts that are used are much smaller in size than the size prescribed in both the standards. The requirement is to study the critical parameters such as the chamber volume, sample size, reverberation time and cut-off frequency etc. which are affecting the sound absorption property of acoustic material.

Sound Quality (SQ) of brake and clutch pedal assembly plays an important role in contributing to vehicle interior noise and perception of sound. Quiet operation of brake and clutch units also reflects the vehicle built and material quality. Noise emitted from these sub-assemblies has to meet certain acceptance criteria as per different OEM requirements. Not much work has been carried on this over the years to characterize and quantify the same. An attempt has been made in this paper to study the sound quality of brake and clutch pedal assemblies at component level and validate the same by identifying the parameters affecting SQ. Effect on noise at different environmental conditions was studied with typical operating cycles in a hemi-anechoic chamber. The effect of sensor switches integrated within the clutch and brake pedal on sound quality is analyzed. It is found that the operating characteristics of switches drives the noise and SQ.

With the announcement, as per draft notification GSR 187 (E) dated 19th Feb 2016 issued by MoRTH (Ministry of Road Transport and Highways), on vehicle emission standards to leapfrog from BS IV to BS VI by 2020, diesel engines would be greatly facing challenges to meet the stringent emission requirements of 90% reduction in PM and 50% reduction in NOx emissions simultaneously. Up to BS IV, in-cylinder strategies utilizing higher fuel injection pressure, higher intake boost, lower to moderate EGR, optimized combustion chamber design and lower intake manifold temperature would be sufficient. But meeting emission levels at BS VI levels would require a combination of both in-cylinder combustion control and after treatment system [1]. However, unlike Europe and US markets where wide spread adoption of after treatment solution is viable, for Indian market it would be impeded by infrastructure availability, system cost and cost of ownership.

In order to reduce development time and costs, application of numerical prediction techniques has become common practice in the automotive industry. Among the wide range of simulation applications, prediction of the vehicle interior noise is still one of the most challenging ones. The Finite Element Method (FEM) is well known for acoustic predictions in the low-frequency range. As part of the development of a full sized bus model, noise levels at Driver Ear Levels (DEL) and Passenger Ear Levels (PEL) were targeted. The structural and acoustic analysis were performed for a bus to reduce interior noise in the low-frequency range. Various counter measures were identified and structural optimization/modifications were performed from virtual simulation to reduce the DEL and PEL. Structure-borne noise due to both road-induced vibration and engine vibration were considered by using FEM techniques.

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.

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.

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.

An open wheeled open cockpit high speed car with 800 CC MPFI engine was developed validated and run at 105 kmph. The key focus was to build a car with superior aerodynamic characteristics especially in terms of drag. This work discusses in detail about the design and simulation of car using CFD package followed by Wind Tunnel testing. The design of high speed car starts with design of seat according to the ergonomics of the driver followed by the space frame. Based on the space frame designed, the body panels are sketched and CAD model is developed. The CAD model is imported in CFD package for virtual testing and validated through wind tunnel results. For this 1:3 scale model was manufactured using Rapid Prototyping.