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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.

Foundry industries are very much familiar and rich experience of producing ferrous castings mainly Flake Graphite (FG) and Spheroidal Graphite (SG) cast iron. Grey cast iron material is mainly used for dampening applications and spheroidal graphite cast iron is used in structural applications wherein high strength and moderate ductility is necessary to meet the functional requirements. However, both types of cast iron grades are very much suitable in terms of manufacturing in an economical way. Those grades are commercially available and being consumed in various industries like automotive, agriculture etc, High strength SG Iron grades also being manufactured by modifying the alloying elements with copper, chromium, manganese andcobalt. but it has its own limitation of reduction in elongation when moving from low to high strength SG iron material. To overcome this limitation a new cast iron developed by modifying the chemical composition.

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.

Due to recent advancements in interior noise level and the excessive use of different grade leathers and plastics in automotive interiors, squeak noise is one of the top customer complaints. Squeak is caused by friction induced vibration due to material incompatibility. To improve costumer perception, interior designs are following zero gap philosophy with little control on tolerances leading to squeak issues. Often manufacturers are left with costly passive treatments like coatings and felts. The best option is to select a compatible material with color and finish; however, this will reduce the design freedom. Material compatibility or stick-slip behavior can be analyzed with a tribology test stand. However, this test is performed on a specimen rather than actual geometry. There were instances, when a material pair was found incompatible when tested on a specimen, but never showed any issue in actual part and vice versa.

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.

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.

During the vehicle launch (i.e. moving the vehicle from “0” speed), the clutch would be slowly engaged by the Driver or Transmission Control Unit (in Automatic Transmission/Automatic Manual Transmission vehicle) for smooth torque transfer between engine and transmission. The clutch is designed to transfer max engine torque with min heat generation. During the clutch engagement, the difference in flywheel and gearbox input shaft speed is called the clutch slipping phase which then leads to a huge amount of energy being dissipated in terms heat due to friction. As a result, clutch surface temperature increases consistently, when the surface temperature crosses the threshold limit, the clutch wears out quickly or burns spontaneously. Hence it is crucial to predict the energy dissipation and temperature variation in various components of clutch assembly through virtual simulation.

The present work is focussed on the real-world challenges of a dual mass flywheel (DMF) equipped vehicle in the Indian market. DMFs are widely used to isolate the drivetrain from the high torsional vibrations induced by the engine. While DMFs can significantly improve noise, vibration and harshness (NVH) characteristics of a vehicle, there are multiple challenges experienced in real-world operating conditions when compared with the single mass flywheel (SMF). The present work explains the challenges of using a DMF in a high power-density diesel powertrain for a multi-purpose vehicle (MPV) application in the Indian market. Measurements on the flat-road operating conditions revealed that the DMF vehicle is very sensitive for launch behaviour and requires a higher clutch modulation. Vibration measurements at the driver’s seat confirm that the SMF vehicle could be launched more comfortably at the engine idle speed of 850 RPM.

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.

Till recently supercharging was the most accepted technique for boost solution in gasoline engines. Recent advents in turbochargers introduced turbocharging technology into gasoline engines. Turbocharging of gasoline engines has helped in powertrains with higher power density and less overall weight. Along with the advantages in performance, new challenges arise, both in terms of thermal management as well as overall acoustic performance of powertrains. The study focuses mainly on NVH aspects of turbocharging of gasoline engines. Compressor surge is a most common phenomenon in turbochargers. As the operating point on the compressor map moves closer to the surge line, the compressor starts to generate noise. The amplitude and frequency of the noise depends on the proximity of the operating point to the surge line. The severity of noise can be reduced by selecting a turbocharger with enough compressor surge margin.

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.

The stringent emission regulations coupled with tighter CO2 targets demand extreme optimization of the diesel engines. In this context, it is important to minimize the cylinder bore distortions in cold and hot conditions. The cold bore distortion is primarily due to the assembly forces applied by the cylinder head bolts whereas the hot distortion is a resultant of local metal temperatures and structural rigidity. The present work describes the extreme optimization techniques used to reduce the bore distortion of a modern high power-density (60 kW / lit) diesel engine, Moreover, the benefits of reducing the bore distortion are quantified in terms of cylinder system friction, blowby rate, oil consumption (OC) and ash loading rate of the diesel particulate filter (DPF). An optimized torque plate honing is used to reduce the bore distortion in cold conditions.

Battery Electric Vehicles (BEVs) are gaining momentum all around the world and India is not far behind in terms of EV sales. The principle difference between BEVs and Internal Combustion Engine based Vehicles (hereafter known as ICEs) is that BEVs run on electric motors and don’t have Internal Combustion based engines that generate significant noise while running. The engine noise contributes to noise pollution, but it is useful in alerting the pedestrians about the incoming vehicle and can function as a passive safety system. The lack of such noise can be a safety threat to pedestrians, cyclists, wildlife etc. Many countries around the world have mandated, or are in the process of mandating, a pass-by noise generating system to alert pedestrians about the incoming vehicle. This paper is an attempt to study various pass-by noise generating systems used worldwide in electric four-wheelers.

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.

High speed diesel engines are difficult to start in cold conditions (at subzero temperature) because the cylinder head and cylinder block absorbs heat of compression and thus preventing ignition due to the high surface to volume ratio. Also the coolant and the engine oil become viscous at subzero temperature and make the condition unfavorable for starting. Combustion optimization along with the help of a heating aid can make these engines to start quickly without any engine misbehavior. Cold startability is the ability of an engine to start within a specified time and continue to run without any malfunctioning. Combustion instability will lead to the misfiring of the engine unless it is calibrated properly. The European countries are subjected to a minimum temperature of -20°C to -25°C. So the intention of this work is to optimize the cold startability of Mahindra's Multi-Purpose Vehicle (MPV) up to -25°C which is to be sold in European countries.

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.