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The present work discusses the developed simulation model aimed to predict the heat rejection (HR) performance and external pressure drop characteristics of automotive charge air cooler (CAC). Heat rejection and airside pressure drop characteristics of CAC were predicted for the conditions of different charge air mass flow rates and different cooling air velocities. The lack of detailed research on CAC performance prediction has motivated the development of the proposed simulation model. The present 1-D simulation has been developed based on the signal library of AMESIM application tool. Input parameters for this simulation such as core size, tube pitch, tube height, number of tubes, fin density, louver angle, louver pitch, charge air mass flow rate, cooling air velocity, charge air inlet temperature, and ambient temperature. Heat rejection curve and airside pressure drop of CAC were the output of the present simulation.

This paper discusses the methodology setup for grill opening area prediction at the early development phase of the product development lifecycle, using a commercially available 1D simulation tool- AMESIM. Representative under hood has been modeled using Grill, Condenser, Radiator, intercooler, fan, and engine components. Vehicle velocity is used as an input to derive the airflow passing through the grill and other under-hood components based on ram air coefficient, pressure drop through different components (Grill, Heat exchanger, Fan & Engine). This airflow is used to predict the top tank temperature of the radiator. Derived airflow is correlated with airflow obtained from CFD simulation. A balance has been achieved between cooling drag & fan power consumption at different grill opening areas for target top tank temperature. Top tank temperature has been predicted at two different extreme engine heat rejection operating points.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. The engine cooling system plays a vital role in meeting the stringent emission norms and improving the vehicle fuel economy apart from maintaining the operating temperature of engine. The airflow through vehicle subsystems like the grille, bumper, the heat exchangers, the fan and shroud and engine bay are called as front-end flow. Front end flow is crucial factor in engine cooling system as well as in determining the aerodynamic drag of vehicle. The airflow through the engine compartment is determined by the front-end vehicle geometry, the CRFM and CAC package, the engine back restriction and the engine compartment geometry including the inlet and outlet sections. This paper discusses the 1D modelling method for front-end airflow rate prediction and thermal performance by 1D method. The underbody components are stacked using heat stack and simulated in pressure mode.

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.

Connected vehicle services have come a long way from the early days of telematics, both in terms of breadth of the class of vehicles, and in terms of richness or complexity of the data being handled for Enhancing Customer Experience. The Connectivity Control unit (CCU) is a gateway device for the vehicle to the outside world. While it enables transmission of vehicle data along with the location information. CCU is currently validated in the vehicle to check functionality. It has cost, time drawbacks and prevents effective testing of many scenarios. Bench level validation will not be able to complete functionality validation. There is subset of validation tools or semi-automated solutions are available in the market, but they are not fully functional, and critically cannot perform end to end validation. Automated Test setup for CCU in lab simulating the entire field data of the vehicle with modifiable characteristics.

Major focus was given on the Comfort, Fuel efficiency & Safety during the development of the passenger cars, which certainly drives the vehicle business of Original Equipment Manufacturer (OEM’s). The air Conditioning in a car, plays an important role in the area of comfort of the passengers and fuel efficiency point of view. Especially Heat Exchanger plays a pivotal role in the air conditioning system. So, it’s a challenge for the OEM’s to select and design the optimal heat exchanger from the supplier, which meets the performance and packaging requirements during the design phase of the product development cycle. The objective of this paper to focus on analytical calculation or framework was developed using an excel tool considering the effect of variable geometry of fin which includes louver pitch, louver angle and louver length in a multi-pass condenser. Further, this theoretical calculation was validated using experimental data and CFD simulation.

In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

As the FTP-75 drive cycle does not have a prescribed gear shift pattern, automotive OEMs have the flexibility to design. Conventionally, gear shift pattern was formulated based on trial and error method, typically with 10 to 12 iterations on chassis dynamometer. It was a time consuming (i.e. ~ 3 to 4 months) and expensive process. This approach led to declaring poor fuel economy (FE). A simulation procedure was required to generate a gear shift pattern that gives optimal trade-off amongst conflicting objectives (FE, performance and emissions). As a result, a simulation tool was developed in MATLAB to generate an optimum gear shift pattern. Three different SUV/UV models were used as test vehicles in this study. Chassis dyno testing was conducted, and data was collected using the base and optimized gear shift patterns. Dyno test results with optimized gear shift pattern showed FE improvement of ~ 4 to 5% while retaining the NOx margin well above engineering targets.

Exhaust gas recirculation (EGR) is an effective strategy to control NOx emissions in diesel engines. EGR reduces NOx through lowering the oxygen concentration in the combustion chamber, as well as through heat absorption. The stringent emission norms have forced diesel engines to further improve thermal efficiency and reduce nitrogen oxides (NOx). Throttle control is adopted in diesel intake system to control the EGR & fresh charge flow and to meet the emissions norms. In three or lesser cylinder. diesel engines, predominantly single and two-cylinder diesel engines, there is a higher possibility of the exhaust gas reaching the intake throttle and Particulate matter getting deposited on the throttle body. This can significantly affect the idling stability and intake restriction in prolonged usage. In idling condition, the clogged throttle body stagnates the fresh charge from entering the cylinder. The work aims at the study of flow pattern for EGR reaching the throttle body.

In the era of fierce competition, launching a defect free product on time would be the key to success. In a modern automobile, the transmission system is designed with utmost care in order to transfer the maximum power from engine to driveline smoothly and efficiently. Optimized design of all the transmission components is necessary in order to meet the power requirement with the least possible weight. This optimization may require gear designs with different internal diameters. The assembly of these gears may not be possible on a solid transmission shaft. To facilitate assembling while retaining optimum design of transmission parts, a separate bush is designed to overcome this limitation. Some bushes may require a flange to restrict any free play of the mounted gear in its axial direction. During complete system level testing of one newly developed manual transmission, bush failure was observed.

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.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. Even if there is a slight reduction in product cost and time has a high significant impact on business. Engineers are under tremendous pressure to develop competitive and give better product concern resolution at the earliest. To arrest the failure of this thermostat vent, an innovative approach was used to relocate de-aeration restrictor on the hose to the thermostat root. Thus, resolving the product concern by increasing the strength of the vent at root and providing good business impact on cost savings. Physical testing has provided an effective way to smoothen product development for concern resolution. This Paper highlights approach on an attempt to field failure simulation with existing and modified design with lab test results.

This paper explains the methodology to design a high power-density diesel engine capable of 180 bar peak firing pressure yet achieving the lowest level of mechanical friction. The base engine architecture consists of an 8 mm crank-offset which is an optimized value to have the lowest piston side forces. The honing specification is changed from a standard plateau honing to an improved torque plate slide honing with optimized surface finish values. The cumulative tangential force of the piston rings is reduced to an extreme value of 28.5 N. A rectangular special coated top ring and a low-friction architecture oil ring are used to reduce the friction without increasing the blow-by and oil consumption. A special low-friction coating is applied on the piston skirt in addition to the optimized skirt profile to have reduced contact pressure. The piston pin is coated with diamond-like carbon (DLC) coating to have the lowest friction.

The ever-increasing customer expectations put a lot of pressure on car manufacturers to constantly reduce the noise, vibration, and harshness (NVH) levels. This paper presents the holistic approach used to achieve best-in-class NVH levels in a modern high-power density 1.5 lit 4-cylinder diesel engine. In order to define the NVH targets for the engine, global benchmark engines were analysed with similar cubic capacity, power density, number of cylinders and charging system. Moreover, a benchmark diesel engine (considered as best-in-class in NVH) was measured in a semi-anechoic chamber to define the engine-level NVH targets of the new engine. The architecture selection and design of all the critical components were done giving due consideration to NVH behaviour while keeping a check on the weight and cost.

Automated manual transmission (AMT) is often preferred by car manufacturers as entry-level automation technology. The AMT technology can provide the comfort of an automatic gearbox at a reasonable cost impact over manual transmission (MT). This paper explains the unique approach to define the gear-shift map of a compact sports utility vehicle (SUV) considering the unique requirements of the Indian market. The real-world measurements revealed that an aggressive shift pattern with delayed upshifts and quick downshifts can deliver good low-end drivability and performance while compromising on fuel economy (FE). Moreover, the chassis dyno measurements in the modified Indian drive cycle (MIDC) indicated lower FE values. On the other hand, a shift pattern with early upshifts and delayed downshifts could help in achieving a better FE while compromising on drivability and performance. Hence, a unique approach is used to derive the most optimal gear-shift map for each operating gear.

Child injury performance evaluation is becoming critical part of almost all legal and consumer ratings-based vehicle safety evaluation protocols. Most of New CAR Assessment Programs (NCAP) now have separate ratings exclusively to evaluate child restraint system effectiveness and child dummy performance under various crash testing modes. OEM’s have need and challenge to maximize injury performance. Sled tests are conventionally used for tuning restraints like seat belts and airbags for driver and co-driver under various frontal type test conditions. However, second row seats are used for CRS/ Child injury performance evaluations. In the present study an attempt is made to simulate child injury performance of P3 dummy positioned on second row seat on defined child seat for 64 kmph frontal Offset deformable barrier type test conforming to Global NCAP. Sled pulses are carefully tuned to capture key injury patterns. Thence restraint parameters are tuned to improve child dummy injuries

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.