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Euro 6 emission norms are getting implemented in India from April 2020 and it is being viewed as one of the greatest challenges ever faced by the Indian automotive industry. In order to achieve such stringent emission norms along with top performance for vehicle, a good strategy should be incorporated to control system out NOx emissions and soot regeneration. Extruded Vanadium catalyst is deployed for this passive regeneration system with DOC (Diesel Oxidation Catalyst), DPF (Diesel Particulate Filter) and SCR (Selective Catalyst Reduction), where the amount of catalyst loading in DOC plays an apex role in deciding conversion efficiency of SCR and passive regeneration capabilities. This study mainly focuses on the impact of catalyst loading of DOC over SCR efficiency. NO2 to NOx ratio should be close to 0.5 for optimum conversion efficiency of SCR. Catalyst loading in DOC decides the amount of NO2 coming upstream to SCR.

Euro 6 emission norms are getting implemented in India from April 2020 and it is being viewed as one of the greatest challenges ever faced by the Indian automotive industry. In order to achieve such stringent emission norms a good strategy will be to optimize the engine out emission through in cylinder emission control techniques and a right sized after treatment system has to be used for this optimized engine. There exist several factors and trade-off between these should be established for in cylinder optimization of emissions. Since the turbocharger plays an apex role in controlling both the performance and engine out emissions of a CI engine, turbocharger selection is a crucial step in the development of new generation of Euro 6 engines in India. Such engines are equipped with additional actuators such as Intake Throttle Valve and Exhaust Throttle Valve and combination of these flap operations with turbocharger output plays a prominent role in controlling performance and emission.

Turbo lag is a very common phenomenon with all diesel engines using the turbo charger to boost power output from an engine. Naturally aspirated diesel engine which is more polluting, heavier, having higher power losses makes a diesel engine more lethargic. Turbocharged diesel engine is fuel efficient, having lower emissions and better power. A smaller sized turbocharged diesel engine delivers power equivalent to larger sized engine; Turbo Lag is the time required to change power output in response to throttle inputs. Turbo lag results in slow increase of speed when we press the accelerator pedal. Turbo lag becomes a real cause of concern when rapid changes in power are required. This is due to the time required for a turbocharger and exhaust system to generate the required boost.

Diesel engines are facing stringent norms and future survival with its lower availability is one of the biggest concerns for OEMs of heavy duty commercial vehicles. This is leading to uplifting of new, latent and innovative techniques to achieve these norms with best possible BSFC to reduce overall diesel consumption. The prime objective of this study is to identify and explore the latent strength of pre and post injection on engine performance, emissions and oil dilution due to soot. The post injection strategy has the potential to reduce soot with almost same NOx and fuel consumption depending on the delay of post injection and its quantity. It aids to increase the engine out temperatures for assistance of after-treatment devices, thus meeting higher temperature requirements for NOx and PM conversion for stringent norms of BSVI.

Air Pollution is a major concern in our country due to which Indian Government has taken a decision to move from BS-IV to BS-VI which is nearly 90% reduction in NOx and 50% in particulate matter along with addition of particulate number regulation for BS-VI in comparison to BS-IV norms in very short span of time. Vehicle manufacturers are also having the challenge to produce low cost and fuel efficient product with BS-VI solution in order to meet tightening emission regulations and increasing needs of lower fuel consumption. Detailed study is done with different approaches to meet BS-VI emission which is elaborately explained in different aspect of engine design and after treatment parameter with its pros and cons. After Treatment selection plays an important role in engine development to meet stringent emission legislations and customer demands. Strategies for BS-VI were described with the advantage and drawbacks for after treatment selection.

BSIV implementation for commercial vehicle in pans India effectively from April 2017. It’s very challenging job for performance and emission engineer to meet engine performance & fuel economy with stringent emission norms for high power and torque density HD diesel engine. In Altitude, lack of air availability & combustion energy passes by mechanical waste gate, lead to lower boost at partial load in waste gate region; which in turn leads to poor engine performance & fuel efficiency and higher turbo speed. To control the turbocharger design speed limit various methodologies adopted like engine derating or optimizing the combustion parameters leads to poor vehicle performance. Combustion parameter optimsation is having limited scope for turbocharger speed control.

Selective Catalytic Reduction has established itself to significantly reduce NOx emissions from diesel engines. Typically, in this technology, aqueous urea solution is injected into hot exhaust stream which chemically decomposes to form ammonia and then reacts with NOx to form safe byproducts as H2O and N2 over the catalyst surface. However, incomplete thermal decomposition of urea not only reduces the NOx conversion efficiency and increases the ammonia slip, but also leads to the formation of solid crystals that adversely affect the performance of the system by increasing the back pressure and lowering the overall fuel economy. The present study discusses about the main reasons that lead to crystal formation in a vanadium based SCR system on a six cylinder 5.6l diesel engine and also design considerations of decomposition tube that affect the formation of crystals and ways to mitigate them.

Nowadays technology is changing day by day and so as the expectation of the customers. Customers relate their vehicle and their reputation. Smoke coming out of vehicle affects badly on the reputation of the customer that is why today’s customer wants smoke free vehicle during transient condition. Low Air Fuel Ratio leads to smoke due to rich combustion mixture. Smoke could be generated due to turbo leg, sudden acceleration, gear changing, cold condition, altitude etc. During sudden acceleration, turbo leg leads to rich mixture which is favourable condition for smoke generation. It is difficult to reduce turbo leg in waste gate type turbocharger while maintaining EGR requirement in EGR based Engine. Smoke can be optimized by controlling fuelling in sudden acceleration or in transient condition. However it might adversely affect on vehicle pick up and could improve fuel economy.