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Engine calibration involves the interaction of electronic components with various engine systems like intake system, exhaust system, ignition system, etc. Emissions are the by-products of combustion of fuel and air inside the combustion chamber. After-treatment systems generally take up the responsibility to scrape out harmful emissions from the engines. However, a good engine calibration will focus on emission reduction at source i.e., during the combustion itself. Thus, the intake of air and fuel in proper amount at each engine operating point is crucial for optimized engine performance and minimal emissions. The Intake system is an integral part of any internal combustion engine and it plays an important role to improve its performance and emission. Generally, for a SI engine, maintaining the stoichiometric A/F ratio is a challenging endeavour from an operational standpoint.

Due to recent infrastructural development and emerging competitive automotive markets, there is seen a huge shift in customer’s demand and vehicle drivability pattern in commercial vehicle industry. Now apart from ensuring better vehicle durability and best in class tyre life and fuel mileage, a vehicle manufacturer also has to focus on other key attributes like driver’s safety and ride comfort. Thus, for ensuring enhanced drivability, key parameters for ensuring better vehicle handling includes optimization of bump steer and brake steer. Both bump steer and brake steer are vehicle’s undesirable phenomenon where a driver is forced to constantly make steering wheel correction in order to safely maneuver the vehicle in the desired path.

CNG has proven to be a concrete alternative to gasoline and diesel fuel for sustained mobility. Due to stringent emission norms and sanctions being imposed on diesel fuel vehicles, OEMs have shifted their attention towards natural gas as an efficient and green fuel. Newly implemented BS VI emission norms in India have stressed on the reduction of Nitrogen Oxides (NOx) from the exhaust by almost 85% as compared to BS IV emission norms. Also, Indian Automotive market is fuel economy cautious. This challenges to focus on improving fuel economy but without increase in NOx emissions. Exhaust Gas Recirculation (EGR) has the potential to reduce the NOx emissions by decreasing the in-cylinder temperature. The objective of the paper is to model a CNG TCIC engine using 1D simulation in order to optimize the NOx emissions and maintain exhaust temperatures under failsafe limits.

Due to increasing pollution and climatic cries, newly implemented BS-VI emission norms in India have stressed the reduction of emission. For which many automobiles have been shifted to alternate fuels like CNG. Also, the Indian Automotive market is fuel economy cautious. This challenges to focus on improving fuel economy but without an increase in emissions. Crankcase blow-by gases can be an important source of particulate emission as well as other regulated and unregulated emissions. They can also contribute to the loss of lubricating oil and fouling of surface and engine components. Closed Crankcase Ventilation (CCV) or Open Crankcase Ventilation (OCV) is capable to reduce particulate emissions by removing the oil mist that is caused mainly due to blow-by in the combustion chamber. This paperwork is focused, to measure the effectiveness of the CCV and OCV systems on the engine-out emissions, primarily on the particulate emissions.

In heavy duty diesel engines, exhaust gas recirculation is often preferred choice to contain NOx emissions, in this a part of exhaust gas is tapped from exhaust manifold or later and recirculated to air intake pipe before intake manifold. Critical to such engines is the design of air intake pipe and intake manifold combination in view of proper exhaust gas mixing with intake air. The variation in exhaust gas mass fraction at each intake port should be as minimal as possible and this variation must be contained within +/− 10% band to have a minimal cylinder to cylinder variation of pollutants. Exhaust gas homogeneity for various intake configurations was studied using three-dimensional computational fluid dynamics for a 4 cylinder, 3.8 L, Diesel fuelled, common rail, turbocharged and intercooled heavy duty engine. Flow field was studied in the computational domain from the point before exhaust gas mixing till all the four intake ports.

A methodology for design and development of commercial vehicle cooling system is derived with an objective to minimize part cost, engineering resources and time to market. This approach is very useful in companies with more variant of engines and vehicles. For this it is identified to have a common cooling system for a set of engines. A systematic approach to develop cooling system based on heat rejection is conceptualised. Engines are classified based on heat loads in to various groups. The cooling package selected for a particular group is independent of type of vehicle (bus or truck), cab (day, sleeper, FES or FBS), Type of drive (LHD or RHD), Emission norm (BSIII or BSIV) and fuel (Diesel or CNG). These packages will cover up the entire range of vehicles and engines. The packaging space available for each group is derived and the cooling package size is finalised. Fan and fan pulley options are listed based on air flow and fuel efficiency requirements.