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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.

With the increase in the number of automobiles on road, there is a very strong emphasis on reducing the air pollution which led to evolution of stringent emission norms. To meet these stringent emission norms, the ideal solution is to optimize the engine hardware and the combustion system to reduce the emission at source thereby reducing the dependency on exhaust after treatment system. Gasoline Direct Injection (GDI) engines are gaining popularity worldwide as they provide a balance between fun to drive and fuel efficiency. Controlling the particle emissions especially Particle Number (PN) is a challenge in GDI engines due to the nature of its combustion system. In this study, experiments were performed on a 1.2Litre 3-cylinder 250bar GDI engine to capture the effect of injection strategies on PN.

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.

Rotavator is an active tillage implement for breaking the Soil and for the preparation of seed bed for cultivation. The Farmers are currently facing problem due to usage of sub optimal speed of Rotavator which results in more fuel consumption, takes more time for completion of operation. Also, the Current Rental models work on Tractor + Implement as rental combination and customer not able to rent Rotavator as a standalone implement due to non-availability of Tracking information such as hours of utilization on Rotavator. Farmers not able to maintain the service periodicity, if oil change not done in prescribed duration then it may result in improper maintenance and breakdown of the Rotavator. To overcome these problems a smart Rotavator developed consists of an electronic unit fitted on the Rotavator shaft to measure the speed of the shaft rotation and in turn convert to Rotavator speed and also able to convert into Hours of usage based on the starting and stopping of the rotavator.

There is a higher demand for quieter tractors in the agri-industry, as the continued exposure to noise levels have disastrous effects on operator’s health. To meet the world-wide regulatory norms and to be the global market leader, its mandatory to develop the comfortable tractor which meets homologation requirements and customer expectations. Typically, Operator Ear Level (OEL) noise has been evaluated in the test, after First Proto has been made. This approach increases cost associated with product development due to late changes of modifications and testing trails causing delay in time-to-market aspect. Hence, there is a need to develop the methodology for Predicting tractor OEL noise in virtual environment and propose changes at early stage of product development. At first, full vehicle comprising of skid, sheet metals and Intake-exhaust systems modelled has been built using Finite Element (FE) Preprocessor.

Fuel efficiency is critical aspect for commercial vehicles as fuel is major part of operational costs. To complicate scenario further, fuel efficiency testing, unlike in passenger cars is more time consuming and laborious. Thus, to save on development cost and save time in actual testing, simulations plays crucial role. Typically, actual vehicle speed and gear usage is captured using reference vehicle in desired route and used it for simulation of target vehicle. Limitation to this approach is captured duty cycle is specific to powertrain and driver behavior of reference vehicle. Any change in powertrain or vehicle resistance or driver of target vehicle will alter duty cycle and hence duty cycle of reference vehicle is no more valid for simulation assessment. This paper demonstrates approach which uses combination of tools to address this challenge. Simulation approach proposed here have three parts.

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.

During the cold start conditions engine must overcome higher friction loss, at the cost of fuel penalty till the optimum temperatures are reached in coolant and lubrication circuits. The lower thermal capacity of the lubrication oil (with respect to the coolant) inverses the relation of viscosity with temperature, improves engine thermal efficiency benefit. Engine oil takes full NEDC test cycle duration to reach 90°C. This leads to higher friction loss throughout the test cycle, contributing a significant increase in fuel consumption. Increasing oil temperature reduces viscosity, thereby reducing the engine friction. This helps to identify the focus for thermal management in the direction of speeding up the temperature rise during a cold engine starting. This work aims at the study and experiment of an exhaust recovery mechanism to improve the NEDC fuel economy.

Within the last decade, due to increasing fuel prices, unstable political situation in major oil producing nations and global warming, there is an increased demand for fuel efficient and environment friendly vehicles. In this context, research is being concentrated in the field of advanced, greener powertrain configurations ranging from hybrids to EVs to fuel cells to HCCI engines. The efficacy for any of the above stated powertrain technology, lies in the optimum component specification. Component specification, operational reliability, & life prediction are highly dependent on the traffic condition, driving nature and vary from country to country. For developing countries, like India, where the traffic & drive pattern are dense & slow moving, there is a dire need for generating load cycle based on Real World Usage Profile (RWUP). The paper will propose a systematic approach to create load cycles in order to derive component specifications for the powertrain based on RWUP.

Gear design is one of the most critical components in the Mechanical Power Transmission industry. Among all the gear design parameters pressure angle is the most critical parameter, which mainly affects the load carrying capacity of the gear. Generally gears are designed with a symmetric pressure angle for drive and coast side. It means that both flank side of gear are able to have same load carrying capacity. In some applications, such as in wind turbines, the gears experience only uni-directional loading. In such cases, the geometry of the drive side need not be symmetric to the coast side. This allows for the design of gears with asymmetric teeth. Therefore new gear designs are needed because of the increasing performance requirements, such as high load capacity, high endurance, long life, and high speed. These gears provide flexibility to designers due to their non-standard design.

Engine radiated noise has complex behavior as engine assembly consist different components, varying dynamic forces with wide range of speed. For open station tractor, engine noise is major contributor and hence needs to be optimized for regulatory norms as well customer comfort. The awareness about NVH comfort in domestic market as well as export market is increasing as customer have become more demanding. This forces OEM’s to put serious efforts to ensure the OEL noise / Engine noise is at acceptable levels. Identifying the optimized countermeasures to reduce the engine noise during the early design phase has a greater impact in reducing product development time and cost. This paper describes about a process that has been established for evaluating engine radiated noise and to improve the overall NVH performance.

With the increasing need to have faster product development and yet achieve the optimum design, thrust on accurate FEA of components and system is felt. The connecting rod is an important component of the crank train and it has a significant mass contribution in multi-cylinder engine. Principal focus is directed to connecting rods having load ratio greater than or equal to 2. As the connecting rod operates in elastic range (i.e. high cycle fatigue life region) stress life approach is adopted for fatigue life evaluation. The three fold purpose of this paper is to establish an accurate FE modelling technique and analysis procedure that simulates the test conditions, aids in accurate fatigue life prediction and most importantly provides a simple procedure for virtual validation of connecting rod. To achieve this objective static strain measurement and fatigue test of connecting rod is carried out on a test bench.

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.

Validation of vehicle structure by use of finite element analysis is at the core of reduction of product development time. In the early phase of validation it is required to evaluate the strength of the vehicle structure to account for the loading during physical validation and service loading. In service the vehicle is subjected to variable loads. These act upon the components that originate from road roughness, maneuvers and power train loads. All systems in the vehicle represent more or less complicated elastic structures subjected to time varying loads. A time domain dynamic assessment of the vehicle structure is time consuming and expensive. Also in the early phase of design wherein several design iterations need to be carried out for design validation, it is practically impossible to conduct a dynamic analysis and fatigue life assessment. Extreme static load cases are traditionally being used for this process.

This paper details about the approach and challenges in converting a conventional vehicle platform designed for diesel/gasoline powertrain into an electrified one. It is not always feasible to accommodate electric powertrain in conventional platforms based on the target requirements. Electrification of conventional vehicles will cut back dependence on fossil fuels, emission of greenhouse gases and emission of pollutants. Fossil fuel are going to be depleted in few decades. Moreover, the emission from traditional vehicle has raised a huge threat to the atmosphere. Auto OEM’s have recognized that electric drive vehicles are critical to the future of the industry. However, some difficulties exist to more noteworthy selection: the view of cost, EV range, access to charging, potential impacts, and absence of open mindfulness about the accessibility and common sense of these vehicles.

This paper details the methodology used to show the importance of Low rolling resistance tires in Electric Vehicles. Fuel efficiency and range is paramount with most of the electric vehicle buyers. Although many people are now becoming aware of low rolling resistance tires but its development started way back in 1990’s. It is always challenging to achieve low rolling resistance in smaller tires of size 12 inch or 13 inch along meeting the other critical vehicle parameters such as ride and handling, NVH, durability and many more. The reduction in rolling resistance can also affect the traction properties of tires. In case of very low rolling resistance tires the traction will be very less but it can badly affect the other vehicle parameters. Selection of tires further depend upon the RWUP (Real World Usage Profile). It means the vehicle is targeted for which region and what is the condition of roads there.

Indian Automobile Industry has started using Six Sigma for Vehicle Design and process improvement to compete with Global competition. This Paper describes how the Tools of Six Sigma shall be used as an Effective Tool for both redefining the Design and the Process Improvement. This Paper talks on the evolution of DMADV approach in Indian Automobile Industry compared to the related Trends in Other Manufacturing Sectors. The Author describes how the warranty failures in Commercial Segment Vehicle Category which was the selling talk for the Competition was addressed in Leading Indian Automobile OEM. As this Failure was adversely impacting customer satisfaction and no solution seemed forthcoming, top Management indicated to use a radically different approach to solve the problem within a years’ time.

The noise and vibration performance of diesel fueled automotives is critical for overall customer comfort. The stationary vehicle with engine running idle (Vehicle Idle) is a very common operating condition in city driving cycle. Hence it is most common comfort assessment criteria for diesel vehicles. Simulations and optimization of it in an early stage of product development cycle is priority for all OEMs. In vehicle idle condition, powertrain is the only major source of Noise and Vibrations. The key to First Time Right Idle NVH simulations and optimization remains being able to optimize all Transfer paths, from powertrain mounts to Driver Ear. This Paper talks about the approach established for simulations and optimization of powertrain forces entering in to frame by optimizing powertrain mount hard points and stiffness. Powertrain forces optimized through set process are further used to predict the vehicle passenger compartment noise and steering vibrations.

Turbocharged common rail direct injection engines offer multiple benefits compared to their naturally aspirated counterparts by allowing for a significant increase in the power and torque output, while simultaneously improving the specific fuel consumption and smoke. They also make it possible for the engine to operate at a leaner air/fuel mixture ratio, thereby reducing particulate matter emission and permitting higher EGR flow rates. In the present work, a two cylinder, naturally aspirated common rail injected engine for use on a load carrier platform has been fitted with a turbocharger for improving the power and torque output, so that the engine can be used in a vehicle with a higher kerb weight. The basic architecture and hardware remain unchanged between the naturally aspirated and turbocharged versions. A fixed geometry, waste gated turbocharger with intercooling is used.

Recently fuel economy and stringent emission norms are the ever growing concern in automotive global scenario. So, automotive engineers are constantly seeking new cost effective methodologies and techniques to achieve considerable weight reduction and improved performance. Nowadays Automotive OEMs are using Aluminum Oil sump (which is a structured part of an engine and supports considerable amount of transmission housing weight) for better emission, reducing the engine height, engine weight and NVH levels. Our present work reveals the concept of ‘Hybrid oil sump’ which made by sheet metal and aluminum in such a way that weight and cost reduced by 20% and 30 % respectively, without compromising NVH and strength properties. Exactly it deals the iteration part of design to arrive the optimum model, various structural modifications since it carries considerable amount of weight of transmission.