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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.

Dual mass flywheel (DMF) is an excellent solution to improve the noise, vibration, and harshness (NVH) characteristic of any vehicle by isolating the driveline from the engine torsional vibrations. For the same reason, DMF’s are widely used in high power-density diesel and gasoline engines. However, the real-world usage conditions pose a lot of challenges to the robustness of the DMF. In the present work, by capturing the Real-World Usage Profile (RWUP) conditions, a new methodology is developed to evaluate the robustness of a DMF fitted in a Sports utility vehicle (SUV). Ventilation holes are provided on clutch housing to improve convective heat transfer. Improvement in convective heat transfer will increase the life and will reduce clutch burning concerns. Cities like Mumbai, Chennai, Bangalore, roads will have clogged waters during rainy season. When the vehicle was driven in such roads, water enters inside the clutch housing through ventilation holes.

The Indian automotive industry has migrated from BS IV (Bharat stage IV) to BS VI (Bharat Stage VI) emission norms from 1st April 2020. This two-step migration of the emission regulations from BS IV to BS VI demands significant engineering efforts to design and integrate highly complex exhaust after-treatment system (EATS). In the present work, the methodology used to evaluate the EATS of a high power-density 1.5-liter diesel engine is discussed in detail. The EATS assembly of the engine consists of a diesel oxidation catalyst (DOC), a diesel particulate filter with selective catalytic reduction coating (sDPF), urea dosing module and urea mixer. Typically, all these components that are needed for emission control are integrated into a single canning of shell thickness ~1.5mm. Moreover, the complete EATS is directly mounted onto the engine with suitable mounting brackets on the cylinder block and cylinder head.

This paper details the methodology used to prevent Thermal events in a vehicle at design and development stages which can lead to vehicle fire or Thermal events. Vehicle Safety is always been in prime focus for designers while introducing newer products in markets for the customers. It is now common to see vehicles catching on fire in roads and in parking places leading to destruction of the surroundings as well as hazard to the passengers. Thermal events can take place due to the heat dissipated by the heat emitters such as Engine, Turbo, Alternator, Exhaust System etc. So the most critical area where Thermal event can take place are under hood which includes the complete engine compartment and under body. The extent of fire depends on the fire source, characteristics of the materials used in constructing and furnishing the vehicle.

From International Energy Statistics (IES) survey, China, US and India are top three countries in emitting CO2 emissions. Further, worldwide national governments are focused to control CO2 emissions at source by stringent regulatory limits. OEMs and Research laboratories are working on several technology options such as advanced fuel injection system, optimizing in cylinder combustion system, thermal management and reduced engine friction to meet this legal requirements. In this paper, research work focused on improving combustion system through selection optimum bowl geometry and increasing volumetric efficiency through valve timings, profile and intake system using both 1D and 3D-CFD numerical approach. The main objective of this approach to utilize fossil fuel to its maximum potential in a single cylinder Naturally Aspirated (NA) water cooled engine with CRDI.

The Micro-hybrid technology otherwise called as stop start system offers a significant improvement in fuel economy particularly in urban driving conditions, where more often the engine idles unnecessarily at traffic signals/jams. Micro-hybrid technology stops the engine at traffic signals/jams and starts the engine automatically on clearance of traffic signals/jams leading to reduced fuel consumption and emissions. This is achieved by monitoring several vehicle and engine parameters through appropriate sensing elements. In this study, the system architecture and functional definitions of start/stop system is defined. Equivalence class, boundary value and decision-table testing are used to generate test cases. On generation of test cases, their relevance on on-road robustness and scope for optimization towards time/efforts are analyzed. In the process, a matrix of different conditions and criteria are formulated. Under these conditions, the system behavior is evaluated.

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.

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.

Batteries have become increasingly important in automotives with increase in vehicle electrical loads. Therefore the reliability of battery is a critical issue in automotive applications. It has been noticed that most batteries have limited cycle durability, that is, the total capacity drops when a battery is charged and discharged for a number of cycles. If a battery is too weak to offer sufficient energy, it should be replaced at the right time. But current problem is that there is no reliable method to quantify the capacity loss and to estimate the remaining capacity of battery. Complete discharge, which is the only way of capacity estimation, which will effect the battery plates therefore it cannot be used too frequently. This paper summarizes the experimental work in the development of the battery status estimation algorithm.

Selection of EGR system is very complex for a particular engine application. The performance of the EGR system depends highly on the Cooler Heat Transfer Efficiency. Cooler effectiveness drops over a period of operation due to soot deposition, HC condensation, and fuel quality. This phenomenon is called as Cooler Fouling. Fouling cannot be avoided completely but the level of performance drop over time has to be studied and minimized. The minimum pressure drop and the highest efficiency in fouled condition is the target for selection of a cooler. In this study, various parameter combinations like tube shape and profile, tube length, number of tubes, tube diameter, and pitch of corrugations, which influence the cooler performance were tested. A better understanding of each of its effect on cooler effectiveness and fouling behavior was obtained. The tube shape was changed from rectangular to circular, also from smooth surface to corrugate.

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.

This paper discusses design and optimization process for the integration of exhaust manifold with turbocharger for a 3 cylinder diesel engine, simulation activities (CAE and CFD), and validation of manifold while upgrading to meet current BS6 emissions. Exhaust after-treatment system needs to be upgraded from a simple DOC (Diesel Oxidation Catalyst) to a complex DOC+sDPF (Selective catalytic reduction coated on Diesel Particulate Filter) to meet the BS6 emission norms for this engine. To avoid thermal losses and achieve a faster light-off temperature in the catalyst, the exhaust after-treatment (EATS) system needs to be placed close to the engine - exactly at the outlet of the turbocharger. This has given to challenges in packaging the EATS. The turbocharger in case of BS4 is placed near the 2nd cylinder of the engine, but this position will not allow placing the BS6 EATS.

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.

In recent times, Battery electric vehicles (BEV) have gained a lot of popularity since they can contribute immensely to control the urban air pollution. However, to consider the BEVs as a sustainable mobility solution, a significant improvement is needed in several aspects including performance, range, cost, weight and recharging time. In the present work, the acceleration performance of an electric vehicle is improved to match with its diesel variant by optimizing the accelerator pedal map strategy. Due to weight and cost constraints, the battery and electric machine capacity of the electric variant of the vehicle was considerably lower (41 % lesser power and 44% lesser torque). However, the expectation from the customers is to have no noticeable difference in the low-end performance feel between the variants.

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.

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.

Proper lubrication is essential for any gear box & axle to get optimized performance. For getting desired life of gear train, we have to maintain minimum oil level inside the gear box or axle, whereas in case of rotating parts such as bearings and shafts, we have to provide sealing such as o rings & oil seals to stop oil coming out from the housing. But, if sealing is not proper seepage & leakage start and reduce the oil level inside the gear box. Oil deficiency leads to scuffing failure in gears and later occurrence of gear & bearing seizure ultimately fails the system. To sustain proper lubrication, we must seal the interfaces appropriately. There are different types of sealing available. Sealing is also depended on application and its location. To protect seal from external environment, we adopt a unique arrangement called slinger which enhances the life of seal.

Automotive clutches are rotary components which transmits the torque from the engine to the transmission. During the engagement, due to the difference in speed of the shafts the friction lining initially slips until it makes a complete engagement. Enormous amount of heat is generated due to the slippage of the friction lining, leading to poor shift quality and clutch failure. Depending on the road & traffic conditions, and frequency of engagement and disengagement of the clutch, it generates transient heating and cooling cycles. Hill fade test with maximum GVW conditions being the worst case scenario for the clutch. A test was conducted to understand the performance of the clutch, in which clutch burning was observed. The clutch lining got blackened and burning smell was perceived. The friction coefficient drops sharply to a point until it cannot transmit the torque required to encounter the slope. This further worsen clutch slippage and lead to more severe temperature rise.