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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.

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.

The emission norms around the world are continuously changing and getting stringent with every revision. India is on its way to make its emission norms at par with that prevailing in the developed nations. The cold-start condition is an important factor affecting vehicle emissions from gasoline direct injection (GDI) and port fuel injection (PFI) vehicles. In this paper, the effects of change in torque converter losses on emissions are experimentally investigated in a TGDI AT vehicle. The instant engagement of the torque converter puts a sudden load on the engine and thus affects its stability. Thus, to overcome the stability issue, Engine Torque has to be simultaneously increased for smooth engagement. As a result, the likelihood of the slightly leaner air-fuel mixture in the cylinder, which results in higher NOx formation, is much greater in an AT vehicle than that of a similar MT vehicle.

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.

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.

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.

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.

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.

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.

Achieving higher emission norms involves various techniques and it has always been a challenging task on meeting the same. Improving the exhaust temperature is indispensable in order to enhance better conversion efficiency on the after-treatment systems. This paper clearly investigates on the various strategies involved to improve the exhaust temperatures of selective catalytic reduction and post injection strategies to meet the emission norms. On the basis of MIDC operation, key load points were selected and split injections with three pulses were implemented. The variation of both the post injection timing and quantity were performed in this paper in order to evaluate the optimum output. The effect of post injection timing and quantity variation on hydrocarbon emissions, carbon monoxide, diesel oxidation catalyst temperatures was observed on all load points. The above strategy was also evaluated on generating the pressure crank angle data.

Design and development of high-pressure pipe involves number of design validation plans for robust design in diesel engine. The fundamental behavior of two-cylinder diesel engine with parallel stroke involves high vibration which generates stress on components mounted on crankcase resulting into earlier fatigue failure. In this paper, the innovative approach of using optimized design of vibration damper for resolving high vibration stress concerns in fuel system is discussed. The vibration dampers were designed meeting both performance and durability aspects in two-cylinder diesel engine applicable for both passenger and commercial vehicle. This paper highlights the design approach involving experimental stress measurements and design optimization based on part development feasibility.

The Introduction of Corporate Average Fuel Economy (henceforth will be addressed as CAFE) regulations demand suitable technological upgrades to meet the significant increase in targets of vehicle fleet fuel economy. Engine Downsizing and Friction Reduction measures help in getting one step closer to the target. In a Conventional Oil Pump, the pump discharge flow and pressure are a direct function of operating speed. There is no control over lubricant flow which results in increased power and fuel consumption due to its unnecessary pumping characteristics irrespective of the actual engine demand. This paper discusses the introduction of a variable displacement oil pump (henceforth will be addressed as VDOP) that was adapted to a 1.5-liter 3 Cylinder Diesel Engine. This approach helps the system to reduce parasitic losses as the oil flow is regulated based on the mechanical needs of the engine. The flow is regulated with help of a solenoid valve which receives input from the ECU.

Lubrication systems play a major role not only in the durability of modern IC engines but also in performance and emissions. The design of the lubrication system influences the brake thermal efficiency of the engine. Also, efficient lubrication reduces the engine's CO2 emissions significantly. Thus, it is critical for an IC engine to have a well-designed lubrication system that performs efficiently at all engine operating conditions. The conventional lubrication system has a fixed-displacement oil pump that can cater to a particular speed range. However, a fully variable displacement oil pump can cater to a wide range of speeds, thereby enhancing the engine fuel efficiency as the oil flow rates can be controlled precisely based on the engine speed and load conditions. This paper primarily discusses the optimization of a lubrication system with a Variable Displacement Oil Pump (VDOP) and a map-controlled Piston Cooling Jet (PCJ) for a passenger car diesel engine.

In recent time, with inception of BS VI emission regulation with more focus on fuel economy and emission, many engine parts which were conventionally made from metal are getting replaced with plastic components for reducing weight to attain better fuel economy. EGR is commonly used technique to reduce emissions in diesel engine along with after treatment devices. EGR reduces peak combustion temperature inside the combustion chamber thereby reducing NOx. EGR is bypassed from the exhaust manifold, cooled down in EGR cooler and mixed with intake air at upstream of the intake manifold. Throttle valve is used for controlling the charged air flow to cylinders for different vehicle operating conditions. With compact engine layout EGR mixer are often located near to throttle valve thereby increasing the possibility of soot deposition on throttle valve.

Current high rating thermal loaded engines must have super-efficient lubrication system to provide clean oil at appropriate pressure and appropriate lube oil temperature to every part of the engine at all engine RPM speeds and loads. So oil pump not only have to satisfy above parameters but also it should be durable till engine life. Gerotor pumps are internal rotary positive-displacement pumps in which the outer rotor has one tooth more than the inner rotor. The gear profiles have a cycloidal shape. Both are meshed in conjugate to each other. Gerotor takes up engine power through crankshaft and deliver to various engine consumers at required pressure and required time. Over the complete engine rpm speed and loads range, oil pump need to perform efficiently to provide proper functioning of the engine. Otherwise low oil pressure leads to more friction in the pump, seizure of bearings and final failure of the engine .High oil pressure can lead to failure in oil filter, gaskets and seal.