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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.

Aerodynamics of on-road vehicles has come to the limelight in the recent years. Better aerodynamic design of vehicle would improve vehicle fuel efficiency with increased acceleration performance. To obtain best aerodynamic body, the series of design modifications and different testing methodologies must be involved in vehicle design and validation phase. Wind tunnel aerodynamic force measurement, road load determination and computational fluid dynamics were the common methods used to evaluate the aerodynamic behavior of the vehicle body. As a novel approach, the present work discusses about the on-road (Real time) testing methodology that is aimed to evaluate the aerodynamic performance of vehicle body using surface pressure mapping. A 64-Channel digital pressure scanner has been utilized in this work for mapping the pressure at different locations of the typical vehicle body.

It is imperative that all automobile manufacturers conduct vehicle level benchmarking at the initial stage of any new project. From the benchmark information, the manufacturers can set relevant targets for their own vehicles under development. In this regard, an accurate prediction of the engine operating points can improve the correlation of the measured fuel economy of the benchmark vehicle. The present work describes a novel method that can be used for the accurate prediction of the engine operating points of any benchmark vehicle. Since the idea of instrumenting the crankshaft/driveshaft with torque transducers is a costlier and time-consuming process, the proposed method can be effective in reducing the benchmarking. Hence, the objective of this work is to develop a mathematical model to calculate the real-time engine operating points (engine speed and torque) using parameters like vehicle speed, accelerator pedal map, driveline inertia, vehicle coastdown force and gradient.

Turbocharging of diesel engines have undergone various phases of technological advancements proving merits with engine performance. Since VGTs are finding their applications in many automotive engines, it is also crucial on finding out ways to extract maximum benefits from the system. Pneumatic actuated VGTs control the vanes positioning with the help of mechanical linkages and don’t prove good in transient response with relatively slower boost build up. The electronic controlled VGT operates with the aid of DC motor which is linked to the engine management system. The position sensor senses the current position of the actuator which is controlled by the engine management system for delivering the desired boost pressure. The eVGT system thus provides very quick response and accurate control of boost pressure in all the vehicle driving conditions.

Ride comfort, drivability and driving stability are important factors defining vehicle performance and customer satisfaction. The IC powertrain is the source for the vibration that adversely affects the vehicle performance. The IC powertrain is composed of reciprocating and rotating components which result in unbalanced forces, moments during operation and produce vibrations at the vehicle supporting members. The vibration reduction is possible by minimizing unbalanced forces and/or by providing anti-vibration mounts at the powertrain-vehicle interface. The power train is suspended on the vehicle frame via several flexible mounts, whose function is to isolate powertrain vibrations from the frame. Total six different modes of powertrain vibration namely - roll, yaw, pitch, vertical, lateral and longitudinal need to be isolated. Powertrain mount stiffness and location is critical in this regard.

Diesel engines have occupied a significant position in passenger car applications in the present automotive sector. Turbochargers find a very prominent role in diesel engines of all applications in order to achieve desired power and better fuel economy. Gaining higher torque at lower engine speeds with low smoke levels is a very tough task with fixed geometry turbochargers due to availability of lower air mass resulting in higher smoke emissions. Variable geometry turbochargers are capable of providing better torque at lower speeds and reduced smoke emissions on Common Rail Diesel engines. The Variable Geometry Turbocharger types used in this study are straight profile nozzle vanes (sample A) and curved profile nozzle vanes (sample B). The curved profile vanes as seen in sample B results in reduced variation of circumferential pressure distortions.

Differential in Gear Box play vital role in Tractors for assisting it in turning and also to take straight path. Light weight machine always have advantage in terms of fuel economy and performance. Weight optimized rotating part have additional benefits of saving power loss, against stationary dead weight. Differential Housing is such a part, which rotates during the vehicle motion and torque transmission. [1] This paper describes a method by which weight of the Differential Housing is optimized. In this particular body of work, additional constraints of avoiding any change in existing cold forged parts like Bevel Gear & Pinion. This also have additional benefit of enhanced flow of Oil inside Differential Housing for better lubrication of Bevel Gears and Pinion. This resulted in weight saving of Differential Housing and finally fuel economy of Tractor.

This paper deals with the study of the phenomenon of crevice corrosion of aluminium by using an example of a corrosion failure of a joint in the automobile coolant circuit. A number of joint failures were studied to understand the corrosion pattern and for various metallurgical aspects like chemistry, hardness and microstructure. The corrosion products were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). This analysis indicated that the corrosion products mostly contained Aluminium Oxides with other contaminants like chlorides. The studies revealed that the clamped joint of the aluminium part and rubber hose led to the formation of a crevice with the engine coolant acting as the corrosive medium. The corrosion behavior at the location was affected by environmental factors like temperature, pH and chloride contamination.

Air conditioning systems are one of the significant auxiliary loads on the vehicle powertrain. In an Electric Vehicle (EV) where the available energy is limited, it becomes crucial to optimize the overall energy consumption of the auxiliary loads. The major power consuming components in an automotive HVAC system (Heating, Ventilation and Air Conditioning) are: Compressor, Cabin blower, Condenser cooling fan and the Control devices. Significant progress is already made in enhancing the energy efficiency of the above-mentioned power consuming components part of vehicle HVAC system. Alternate energy sources are being explored recently, to reduce the energy demand from vehicle. One such proposal is to harness the abundant solar energy available, through solar panels and consume this energy to supplement the power required for HVAC system components. Solar panels convert solar energy to electrical energy by the principle of the photovoltaic effect.

The complexity of Urban driving conditions and the human behavior introduces undesired variabilities while establishing Fuel economy for a vehicle. These variabilities pose a great challenge while trying to determine that single figure for assessment of vehicle’s fuel efficiency on an urban driving cycle. This becomes even more challenging when two or more vehicles are simultaneously evaluated with respect to a reference vehicle. The attempt to fit a generalized linear model, between Fuel Economy as predicted variable and components of a driving cycle as predictor variables produced oxymoronic and counter-institutive results. This is primarily due to existence of multi-collinearity among the predictor variables. The context of the study is to consider the event of driving on a cycle as a random sampling experiment. The outcome of a driving cycle is summarized into a list of predictor variables or components.

Design of powertrain mounting bracket is always a challenge in achieving good NVH characteristics and durability with less weight. For this activity engine mount load is necessary to optimize the weight to meet durability and NVH targets. This paper introduces a new method to calculate engine mount loads from chassis accelerations. The method starts by measuring chassis acceleration near engine mount location, then reproducing the same chassis acceleration in Multi Axis Shaker Table (MAST), and finally extracting the load in engine mount using testing (using load cell). The MAST test actuator displacement input is imported into ADAMS and engine mount loads are extracted. The extracted loads are correlated with physical test results. The correlation includes load time history and peak-to-peak load range. It is recommended to implement this method in early vehicle design phases. Implementing engine mount bracket weight optimization is desirable in early design stages.

The never-ending concern on the air quality and atmospheric pollution has paved way for more stringent emission legislations. Existing Diesel engine hardware face several problems on meeting the tough emission limits and they require more additional features to comply with the emission standards. The current research work throws light on the air path control approach to meet the Bharat stage 4 emission norms on 2.2 L Sports Utility Vehicle engine operating with EGR cooler and the techniques followed to meet the same emission norms without the application of EGR cooler which was successfully implemented on the vehicles enabling reduction of hardware. Also the migration of 2.2 L engine from 88 kW operating on Compression ratio 18.5 to 103 kW at a lower Compression ratio of 16.5 is a challenging process to achieve Nitrogen oxide emissions reduction at part loads.

Improving the fuel economy of the vehicle resulting in energy conservation on long run is a challenging task in the automotive field without compromising the emission margins. Fuel economy improvement by effective driving is the main focus of this paper by the proper utilization of gears which can enable good fuel economy even when the vehicle is driven by different drivers. GSI technique was implemented on Sports utility vehicle operating with 2.2 l engine. Tests were carried with GSI and the effect of fuel consumption and emissions were compared to the regular driving cycle. Optimization of various gear shifting points were analyzed and implemented for better fuel economy keeping the drivability in mind, meeting the BS4 emission norms comfortably. The experiments were carried out in both cold and hot conditions to check the effect of GSI and positive results of fuel economy improvement was yielded.

The combustion phenomenon of diesel engines has got a very major impact on the performance and exhaust emission levels. Several important factors like engine components design, combustion chamber design, Exhaust gas recirculation, exhaust after treatments systems, engine operating parameters etc. decide the quality of combustion. The role of fuel injector is crucial on achieving the desired engine performance and emissions. Efficient combustion depends on the quantity of fuel injected, penetration, atomization and optimum timing of injection. The nozzle through flow, cone angle, no of sprays and nozzle tip penetration are the factors which lead to the selection of perfect injector for a given engine. This paper focusses on the selection of the best fit injector suiting the BS6 application on evaluating the performance and emission characteristics. Injectors used were with varying cone angles and NTP.

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.

Migration to BS6 emission norms from BS4 levels involves strenuous efforts involving advanced technology and higher cost. The challenging part is on achieving the stringent emission norms without compromising the engine fuel economy, performance and NVH factors. Selection of hardware and attaining an optimal behaviour is therefore vital. This article focuses on the evaluation of three different configuration of turbochargers for the same engine to meet the BS6 emission norms and performance. The turbocharger samples used measure the same compressor diameter with varying trim ratios. Simulation and testing of turbochargers ensured positive results for confirmation of the system. Parameters like low speed torque, smoke and compressor efficiency were evaluated and analysed for all configurations. The safe limits of surge and choke regions of all the compressors were also studied and verified.

Air conditioning systems are one of the significant auxiliary loads on the vehicle powertrain. In an Electric Vehicle (EV) where the available energy is limited, it becomes crucial to optimize the overall energy consumption of the auxiliary loads. The major power consuming components in an automotive HVAC system (Heating, Ventilation and Air Conditioning) are: Compressor, Cabin blower, Condenser cooling fan and the Control devices. Significant progress is already made in enhancing the energy efficiency of the above-mentioned power consuming components part of vehicle HVAC system. Alternate energy sources are being explored recently, to reduce the energy demand from vehicle. One such proposal is to harness the abundant solar energy available, through solar panels and consume this energy to supplement the power required for HVAC system components. Solar panels convert solar energy to electrical energy by the principle of the photovoltaic effect.

With the implementation of stringent PM emission norms in various countries for diesel vehicles, the legislation demands a PM mass limit as low as 4.5mg/km in the NEDC cycle, starting from Euro5. This makes the usage of Diesel Particulate Filters (DPF) mandatory. The same is going to be mandated for upcoming BSV emission norms in India. Thus it becomes imperative to know the functional aspects of a DPF and their impacts. Basically there are two major functions of a DPF- Soot mass filtration and Soot burning or Regeneration. This paper highlights usage of DPF in Indian context from the perspective of one of the major aspects of DPF regeneration-Regeneration Interval, which is basically governed by vehicle/engine out smoke. Regeneration interval also has direct or indirect influence on life of engine of a vehicle and average fuel economy of a vehicle which will also be touched upon herein.

Diesel engines are known for their excellent low-end torque, better drivability, performance, and better fuel economy. The increase in customer demands pushes to deliver higher power and torque along with fuel economy. This requirement puts a great challenge on the overall weight of the engine. This paper explains the holistic approach followed along with optimizing the rocker arm cover to achieve the weight target without compromising on durability and cost in the commercial segment 2.5-liter Diesel Engine. This paper presents a complete overview of the design and development of Rocker Arm (RA) cover to meet Strength, Durability, NVH and Aesthetic in Commercial Engine where base design is in aluminum which is mounted on cylinder head with a separate breather system. From aluminum the base design of Rocker arm cover is optimized to sheet metal where in there is reduction of 43% in weight and cost saving of 13%.

Tractors in the field are exposed to adverse operating conditions and are surrounded by dust and dirt. The tiny, thin and sharp broken straw and husks surround the system in reaper operation. The tractors which are equipped with air conditioning system tend to show detrimental effects in cooling performance. The compressor trips frequently by excess pressure developed in the system due to condenser clogging and hence cooling performance is reduced considerably. The air conditioning performance reduces due to the clogged condenser located on the top roof compartment of operator’s cabin, which is better design than keeping in front of radiator where clogging happens every hour and customer need to stop the tractor to clean it with specific blower.