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With implementation of stringent BSVI emission norms and regulations like OBD-II on vehicle, it is essential to define the life of exhaust after treatment along with the vehicle. Diesel after treatment generally consists of DOC, DPF and SCR. Lubricating oil contains phosphorus and zinc which adversely affect the DOC. Unburned hydrocarbons (UNHBC) and SOF in tail pipe get accumulated in the DPF. This requires regeneration process where in, high temperatures in exhaust after treatment (EATS) burn the adsorbed Sulphur or phosphorus, thereby improving the conversion efficiencies. Repeated regenerations lead to ash accumulation in DPF and this reduces its capability for soot accumulation. Sulphur in the exhaust impacts SCR through NOx conversion. The present study analyzes the effect of (1) Chemical aging (2) Thermal aging on 3.77 liter diesel engine after treatment. A test cycle was prepared to run the durability for EATS.

The intensifying demand of cleaner fuelled vehicles considering current norms of BSIV and upcoming stringent norms of BSVI with low cost solutions has promoted the development of CNG and dual fuel vehicles. CNG vehicle is anticipated to discover its extensive use for environment fortification and effective deployment of energy capitals. Thus, CNG vehicles can be pretty effective in averting environment deterioration. CNG has low carbon to hydrogen ratio, this leads to very low CO2 emissions compared to gasoline and diesel vehicles. CNG engines have the potential of low NOx and particulate emissions. Natural gas vehicle development has been directed on the way to current use of direct injection and port injection with S.I. engines. Generally for low cost development, all OEMs prefer optimization of existing engines. Similarly for this project, a diesel engine was converted to S.I. engine for development of low emission CNG engine.

Diesel engines have always been popular for their low end torque and lugging abilities. With their higher thermal efficiencies through technical advancements, diesel engines are preferred powertrains in mass transportation of goods as well as people [14] [15]. A diesel engine always banks on excess air, which is subjected to higher compression ratios so as to achieve temperatures, enough to facilitate auto-ignition of diesel. With the advent of turbocharging and intercooling, the air availability is further enhanced, ensuring better combustion efficiency, lesser HC, CO and particulate matter (PM) emissions together with improved fuel efficiencies [2] [15]. Higher air availability also has its own shortcomings in the form of higher NOx (Nitrogen oxides) emissions. With stringent emission norms in place, reduction of NOx as well as PM, without sacrificing performance and fuel economy, is of utmost importance.

During the last few decades, concerns have grown on the negative effects that diesel particulate matter has on health. Because of this, particulate emissions were subjected to restrictions and various emission-reduction technologies were developed. It is ironic that some of these technologies led to reductions in the legislated total particulate mass while neglecting the number of particles. Focusing on the mass is not necessarily correct, because it might well be that not the mass but the number of particles and the characteristics of them (size, composition) have a higher impact on health. During the diesel engine combustion process, soot particles are produced which is very harmful for the atmosphere. Particulate matter is composed of much organic and inorganic composition which was analyzed after the optimization of SCR and EGR engine out.

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.

Engine down speeding is rapidly picking up momentum in many segment of world market. Numerous engine down speeding packages from OEM have been tailored to take advantage of the increased efficiencies associated with engine down speeding. Running engine at lower rpm has numerous advantages. The most obvious of these is reduced fuel consumption, since the engine can spend more time running within its optimum efficiency range. By down speeding, the engine is made to run at low speeds and with high torques. For the same power, the engine is operated at higher specific load- Brake Mean Effective pressure (BMEP) which results in higher efficiency and reduced fuel consumption-Brake Specific Fuel Consumption (BSFC). The reasons for increased fuel efficiency are reduced engine friction due to low piston speeds, reduced relative heat transfer and increased thermodynamic efficiency.

Increased options and flexibility in common rail direct injection provides a great opportunity for combustion optimization using fuel and air system with proper combustion chamber configuration. This paper elaborates the experimental work conducted for combustion optimization with combinations of piston bowl, intake port swirl, injector specifications and turbo charging on a 3.8 l four valve diesel engine of LDT application equipped with common rail fuel injection system and waste gate turbo charge. In meeting the target emission norms with internal engine measures, the design of the piston bowl and the nozzle configuration perform a defining role. Through simulations the best option had been carried out parametrically investigate the influence of piston bowl geometry and nozzle characteristics on the performance of the combustion system.

Exhaust gas recirculation is one important measure to achieve the Bharat Stage IV, Bharat Stage V as well as the Euro V emissions legislation. EGR is one of the most promising solutions to reduce NOx to achieve Bharat Stage IV emission norms for any high specific power engine. An emissions and performance study was conducted to explore the effects of EGR and multiple injections on particulate, NOx, and BSFC. Recent work has shown that multiple injections are effective at reducing particulate. Thus, it was of interest to examine the possibility of simultaneously reducing particulate and NOx with the combined use of EGR and multiple injections. The tests were conducted on a four cylinder four valve light duty truck engine. Tests were done at emission modes (A, B & C Modes) with EGR are variation along with different injection strategies. The fuel system used was an electronically controlled, common rail injector and supporting hardware.

Diesel exhaust is a complex mixture of combustion products of diesel fuel, and the exact composition of the mixture depends on the nature of the engine, operating conditions, lubricating oil, additives, emission control system, combustion parameters and fuel composition. In a diesel engine, NOx (NO & NO2) and PM (Particulate Matter) are the most critical constituents for the emission legislation. In order to control the PM emission of diesel engine and comply with increasingly stringent exhaust legislation, more information is required on the components and genesis of PM. In general, PM from diesel engines is classified into two fractions: Insoluble Organic Fraction (ISOF) and Soluble Organic Fraction (SOF). In this experimental study, a series of 13 mode ESC cycle were run on a light duty diesel engine after optimization of combustion parameters (Injection Pressure, Injection Timing, Multiple Injections, EGR rate, etc) in successive tests and PM component was analyzed.

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.

An efficient after treatment technique is driven by the need to maintain strict emission norms for heavy-duty and medium-duty ground vehicles. SCR being an advanced active emission technology system for diesel engine, is one of the most cost-effective and fuel-efficient technologies available for complying with the stringent NOx emission legislations. The design of the SCR system involves catalyst selection, complex controller development like urea dosing strategy and the interaction between engine setup and after treatment system. For this purpose, the SCR model must be computationally efficient to evaluate the complete efficiency along with to take care for the NH3 slip also. The SCR model was prepared with respect to SCR inlet temperature and ratio of NOx and ammonia to study the behavior of NOx conversion efficiency keeping consideration of NH3 slip also required for optimizing the calibration.