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Hydrogen is considered as one of the potential alternate fuel and when compared to other alternate fuels like CNG, LPG, Ethanol etc., it has unique properties due to absence of carbon. In the current work, Hydrogen engine of 2.5 L, four cylinder, spark ignited Turbocharged-Intercooled engine is developed for Mini Bus application. Multi-point fuel injection system is used for injecting the hydrogen in the intake manifold. Initially, boost simulation is performed to select the optimum compression ratio and turbocharger. The literature review has shown that in-order to get the minimum NOx emissions Hydrogen engines must be operated between equivalence ratios ranging from 0.5 to 0.6. In the present study, full throttle performance is conducted mainly with the above equivalence ratio range with minimum advance for Maximum Brake Torque (MBT) ignition timing. At each operating point, the performance, emissions and combustion parameters are recorded and analyzed in detail.

This paper discusses the development of an all speed governed diesel-natural gas dual fuel engine for agricultural farm tractor. A 45 hp, 2.9 liters diesel-natural gas dual fuel engine with a novel closed loop secondary fuel injection system was developed. A frugal approach without any modification of the base mechanical diesel fuel injection system was followed. This approach helped to minimize the cost impact, while meeting performance and emissions at par with neat diesel operation. Additional cost on gas injection system is redeemed by cost savings on diesel fuel. The dual fuel technology developed by Mahindra & Mahindra Ltd., substitutes on an average approximately 40% of diesel with compressed natural gas, meeting the TREM III A emission norms for dual fuel while meeting all application requirements. The governing performance of the tractor was found to be superior than base diesel tractor.

Being a safety critical aggregate, every aspect of brake system is considered significant in vehicles operations. Along with optimum performance of brake system in terms of deceleration generation, brake pedal feel or brake feel is considered as one of the key elements while evaluating brake system of vehicles. There are many factors such as liner and drum condition, road surface, friction between linkages which impress the pedal feel. Out of these, in this paper we will be discussing the factors which influence the brake pedal feel in relation to the driver comfort and confidence building. Under optimum braking condition, brake operation must be completed with pedal effort not very less or not very high, brake pedal feel must be firm throughout the operation, in such a way that it will not create fatigue and at the same time it will give enough confidence to the driver while operating with acceptable travel.

Squeak and rattle concerns accounts for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are major quality concern for automotive OEM’s. Objectionable door noises such as squeak and rattle are among the top 10 IQS concerns under any OEM nameplate. Customers perceive Squeak and rattle noises inside a cabin as a major negative indicator of vehicle build quality and durability. Door squeak and rattle issues not only affects customer satisfaction index, but also increase warranty cost to OEM significantly. Especially, issues related to door, irritate customers due to material incompatibilities. Squeaks are friction-induced noises generated by stick-slip phenomenon between interfacing surfaces. Several factors, such as material property, friction coefficient, relative velocity, temperature, and humidity, are involved in squeak noise causes.

Body-over-Frame is the primary type of construction used in SUVs, pick-ups, and other commercial vehicles in India. In this type of construction, the body, engine, suspensions etc. are mounted on the ladder frame. Since the frame acts as the skeleton of the vehicle, optimal design of frame at the concept stage of the vehicle program is critical for meeting all structural performance targets. Frontloading of these targets aids in architecture development and reduces future design modifications. The natural frequency response from the frame directly affects the NVH performance of the vehicle. This paper focuses on frontloading the natural frequency targets by performing concept-level simulations on the ladder frame even before creation of 3D concept data. A parametric beam model is created based on the reference vehicles. The beam model has been validated with correlation of more than 85% compared with CAE and physical testing outputs of existing vehicles.

With the increasing demand for light weight engines, the design of FEAD (Front end accessory drive) Brackets has gradually shifted from conservative cast iron design to optimized aluminum design. Hence there is a requirement for a virtual validation procedure that is robust and accurate. The FEAD brackets for the engine are subjected to periodic vibrations (engine excitations) and random vibrations (Road excitations), the former being the more dominant of the two as road excitations are isolated by the power train mounts. Hence these brackets are susceptible to fatigue failures. The paper describes a virtual validation procedure adopted for FEAD brackets that gives accurate stress prediction and thereby ensures accuracy in predicted fatigue factor of safety for design. The simulated dynamic stresses are later compared with the test results and a good correlation is observed.

Plenum is the part located between the front windshield and the bonnet of an automobile . It is primarily used as an air inlet to the HVAC during fresh air mode operation. It’s secondary functions include water drainage, aesthetic cover to hide the gap between windshield to bonnet, concealing wiper motors and mechanisms etc. The plenum consists mainly two sub parts viz. upper plenum and lower plenum. Conventional plenum design which is found in majority of global OEMs employ a plastic upper plenum and a metal lower plenum which spans across the entire width of engine compartment. This conventional lower plenum is bulky, consumes more packaging space and has more weight. In this paper, we propose a novel design for the plenum lower to overcome above mentioned limitations of the conventional design. This novel design employs a dry and wet box concept for its working and is made up of complete plastic material.

Brake groan noise is resolved without any major change in the design of brake system and vehicle sub-system components in the development phase of a utility vehicle. The groan noise is observed during the end of the stopping of the vehicle under moderate braking. The concerned NVH issue is perceived as unacceptable noise in the passenger compartment. Groan induced vibration is subjectively felt on steering and seat frame. A typical process is established to successfully reproduce the groan which helped in precisely evaluating the effect of modifications proposed. The temperature range of the disc which has the highest probability to produce the groan noise is found out experimentally. The transfer path analysis is carried out to find the path contributions from suspension. Acoustic transfer functions from considered paths are measured with the suspension removed from vehicle.

In today’s scenario, internal combustion engines have conflicting requirements of high power density and best in class weight. High power density leads to higher loads on engine components and calls for a material addition to meet the durability targets. Lightweight design not only helps to improve fuel economy but also reduces the overall cost of the engine. Material change from cast iron to aluminium has a huge potential for weight reduction as aluminium has 62% lesser mass density. But this light-weighting impacts the stiffness of the parts as elastic modulus drops by around 50%. Hence, this calls for revisiting the design and usage of optimization tools for load-bearing members on the engine to arrive at optimized sections and ribbing profiles. This paper discusses the optimization approach for one of the engine components i.e., the FEAD (front end accessory drive) bracket.

In automotive product development, design and development of the chassis plays an important role since all the internal and external loads pass through the vehicle chassis. Durability, NVH, Dynamics as well as overall vehicle performance is dependent on the chassis structure. Even though passenger vehicle chassis has a ladder frame or a monocoque construction, small commercial vehicle chassis is a hybrid chassis with the cabin welded to the ladder frame. As mileage is critical for sale of SCVs, making a light-weight chassis is also important. This creates a trade-off between the performance and weight which needs to be optimized. In this study, a parametric beam model of the ladder frame & the cabin of the vehicle is created in COMSOL Multiphysics. The structure has been parameterized into the long member & crossmember geometry & sections. The model calculates the first 12 natural frequencies, global stiffness, and weight.

The SAE J1100 based standard cargo volume index methods and predefined luggage objects are very specific to United States population. The European luggage volume calculation and standard luggage calculations are primarily based on DIN and ISO standards. Luggage volume declaration by manufacturers are based on any of these methods. The calculations are complicated and there is a possibility of declaring different values for similar luggage compartments. The major purchase decision of vehicle is based on its luggage capacity and current methods are very limited to make an intelligent decision by a customer. Market specific customer usage patterns for luggage requirements and protecting them in vehicle architecture upfront in concept stage is important to retain the market position and buying preference of customers. The usage patterns is collected from customer clinics and marketing inputs.

The main objective of the project is to develop the hydrogen-fuelled vehicles for transport application. Exhaustive lab tests on engine & vehicle was done to access the hydrogen (H₂) behavior at varying operating conditions. Fifteen such hydrogen-fuelled vehicles were developed by Mahindra with integration of the optimized engine, fuel storage system, fuelling system and safety features to demonstrate these hydrogen vehicles. These vehicles are refueled at a dedicated hydrogen-refueling facility. Detailed calibration was done with hydrogen for meeting the performance and emissions characteristics of the engine. In this experimental investigation Electronic Control Unit (ECU)-based timed manifold injection system was developed. Hydrogen is injected before the intake manifold and the quantity of hydrogen injection is depending on the load, speed and operating conditions.

In Current scenario all Vehicle Manufacturer are looking towards cost effectiveness in their product development without compromising product quality and performance. With this reference, development of low cost FEAD (Front End Accessory Drive) system with stretch fit belt & idlers for multiple accessories has emerged as one of the alternative smart engineering solution against the FEAD with auto tensioner. The beauty of this low cost FEAD system is not only the cost saving but also the long lasting performance without affecting component life. In the current work, development of a low cost FEAD for 3 cylinder 1.5 litre diesel engine has been presented. It was one of the challenges to introduce stretch fit belt for 3 cylinder engine considering the high torsional vibration. The performance of this FEAD system was evaluated in terms of accessories pulley slip and belt flapping. The component durability was assessed both at engine as well as at vehicle level.

Overall in-vehicle visibility is considered as a key safety parameter essentially mandated due to the increasing traffic scenario as seen in developing countries. Driver side bottom corner visibility is one such parameter primarily defined by A-pillar bottom and outside rear-view mirror (OSRVM). While defining the OSRVM package requirements such as size, position and regulatory aspects, it is also vital to consider other influencing parameters such as position of pillars, waist-line height, and Instrument panel which affect the in-vehicle visibility. This study explains the various package considerations, methods to optimize OSRVM position, shape and housing design in order to maximize the in-vehicle visibility considering the road and traffic conditions. A detailed study on in-vehicle visibility impacted by OSRVM packaging explained and had been verified for the results.

Light weighting is the Current trends in automotive to achieve better fuel economy which helps for meeting fuel economy standards & to offset the higher fuel prices. Thus there is a need to develop composite running board which is light weight & structurally sound enough to meet the performance. The present paper provides a composite running board assembly for an automobile. The running board assembly includes a board, an insert body and a plurality of brackets. Upon stepping of a passenger on the board, the board transfers load on the insert body which subsequently transfers the load to the plurality of brackets thus facilitating even distribution of the load on the automobile body. This paper also put lights on the use of improved TRIZ application - an approach to inventive problem solving for designing highly affordable & light weight running board. The cost & weight reduction achieved with innovative design is about 40 % & 35 % comparing to existing cost & weight.

The carbonless structure of Hydrogen is considered as a potential fuel for future automotive propulsion system to reduce reliance on energy imports and elimination of carbon containing emissions. There are a lot of research on fuel cells, which yields very promising results, yet at other side it has several drawbacks such as cost, bulkiness and low efficiency at high loads. Here the hydrogen fuelled internal combustion engine appears on the scene. The working principle of an internal combustion engine fuelled with hydrogen is same as any spark ignition engine. This paper reviews optimistic features and current boundaries that are associated with the use of hydrogen as SI engine fuel, along with the recent advancements in hydrogen (H2) powered engine. An overview of highly favorable engine specific properties of hydrogen with regards to its combustion characteristics and challenges that must be surmounted in order to establish a “Hydrogen Economy” are described.

An inadequate sealing of the combustion chamber gasket interface may have severe consequences on both the performance & emission of an engine. In this investigation, both the distribution of the contact pressure on the gasket and the stresses of the cylinder head at different loading conditions are explored and improved by modifying the design. A single cylinder gasoline engine cylinder head assembly has been analyzed by means of an uncoupled FEM simulation to find the sealing pressure of the multi-layer steel (MLS) gasket, strength & deformation of the components involved. The thermal loads are computed separately from CFD simulations of cylinder head assembly. The cylinder head assembly consisting of head, blocks, liner, cam shaft holder, bolts, gaskets, valve guides & valve seats, is one of the most complicated sub-assembly of an IC engine.

This paper describes vinyl ester based SMC (Sheet molding composite) material for oil sump part in automotive application. This sheet moulding composite is a ready to mould glass-fibre reinforced vinyl ester material primarily used in compression moulding process. This vinyl ester resin is compounded with glass fibre to meet the product functional requirements. Oil sump is a structural component under bonnet that forms the bottommost part of the crankcase and also contain the engine oil before and after it has been circulated through the engine. Generally, metals are preferred material for this application. In this paper, fibre filled vinyl ester based thermoset resin (SMC) material has been explored for oil sump application. They possess excellent properties in terms of tensile strength, modulus, impact strength, dimensional stability, high/low temperature resistance and oil resistance.

Tractor weight transfer is the most common farm-related cause of fatalities nowadays. As in India it is getting mandatory for all safety devices across all HP ranges. Considering any changes in the weight from an attachment such as Rops, PTO device, tow hook and draw bar etc. can shift the center of gravity towards the weight. center of gravity is higher on a tractor because the tractor needs to be higher in order to complete operations over crops and rough terrain. Terrains, attachments, weights, and speeds can change the tractor’s resistance to turning over. This center of gravity placement disperses the weight so that 30 percent of the tractor’s weight is on the front axle and 70 percent is on the rear axle for two-wheel drive propelled tractors and it must remain within the tractor’s stability baseline for the tractor to remain in an upright position.

This paper describes the suitability of recycled polyethylene terephthalate (RPET) material for canopy strip in a commercial vehicle. The material described in this paper is a PET compound recycled from used PET bottles and reinforced with glass fibers so as to meet the product's functional requirements. The application described in this paper is a Canopy strip which is a structural exterior plastic part. Canopy strip acts as a structural frame to hold the Vinyl canopy in both sides of the vehicle. Functionally, the part demands a material with adequate mechanical and thermal properties. Generally, PET bottles are thrown after use thereby creating land pollution. PET being inert takes an extremely long time to degrade thereby occupying huge amount of space in landfills and directly affecting rain water percolation. This work focused on recycling the PET bottles and compounding them suitably so as convert them into useful automotive parts.