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Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines. A dual fuel (Diesel-CNG) engine is a base diesel engine fitted with a dual fuel conversion kit to enable use of clean burning alternative fuel like compressed natural gas. In this engine diesel and natural gas are burned simultaneously. Natural gas is fed into the cylinder along with intake air; the amount of diesel injection is reduced accordingly. Dual fuel engines have number of potential advantages like fuel flexibility, higher compression ratio, and better efficiency and less modifications on existing diesel engines. It is an ecological friendly technology due to lower PM and smoke emissions and retains the efficiency of diesel combustion.

The evolution of engine technology has so far seen the most beneficial side of progress in the fields of transportation, agriculture, and mobility. With the advent of innovation, there is also an impact on our environment that needs to be balanced. This is where fuels like CNG, LPG, LNG, etc. outperform conventional fossil fuels in terms of pollution & operational cost. This paper enlightens on the use of innovative dual-fuel technology where diesel & CNG fuels are used for combustion simultaneously inside the combustion chamber. Dual fuel system adaptation for farm application ensures self-reliance of the farmer where he can generate Bio-CNG to use the renewable fuel for farming making him less dependent on conventional fossil fuel thus promoting a green economy. The dual-fuel system is adapted to the existing in-use diesel engine with minimum modifications. This makes it feasible to retrofit a CNG fuel system on an existing diesel engine to operate it on dual fuel mode.

CNG has recently seen increased penetration within the automotive industry. Due to recent sanctions on diesel fuelled vehicles, manufactures have again shifted their attention to natural gas as a suitable alternative. Turbocharging of SI engines has seen widespread application due to its benefit in terms of engine downsizing and increasing engine performance [1]. This paper discusses the methodology involved in development of a multi cylinder turbocharged natural gas engine from an existing diesel engine. Various parameters such as valve timing, intake volume, runner length, etc. were studied using 1D simulation tool GT power and based on their results an optimized configuration was selected and a proto engine was built. Electronic throttle body was used to give better transient performance and emission control. Turbocharger selection and its location plays a critical role.

Environmental pollution has proven to be a big threat to our eco-system and pollution from automobiles using conventional fuels is a major contributor to this. Alternative fuels are the only immediate option that can help us counter the ever rising environmental pollution. In today’s date we cannot directly replace an IC engine, so the most efficient option available is using a fuel that can work with the IC engines other than gasoline and diesel. CNG proves to be the most promising fuel. A diesel engine converted to stoichiometric CNG engine was used for optimization. The paper deals with the improvement of engine power from 50HP to 60HP and up-gradation of the emission from BS-III to BS-IV norms of a multi-cylinder naturally aspirated engine. This was achieved by varying the compression ratio, valve-lift profile, intake plenum volume, runner length, spark-advance timing, fuel injection location, exhaust pipe length and catalytic converter selection.

Single cylinder and two cylinder diesel engines are widely used as a source of power generation, three wheelers, agricultural machines and in small house-hold applications in India as well as other Asian countries. Use of high end technologies in such engines are very expensive and also becoming complex. Therefore simple mechanically controlled components are used for these engines which make them simple in operation and maintenance. In order to meet stringent emission norms, there is a need for the development of these engines. In the present work, an existing two cylinder naturally aspirated DI diesel engine is upgraded with Turbocharged & Intercooled (TCIC) version to meet the revised stringent stage-II emission limits. The two cylinder diesel engine has been upgraded with optimum selection of turbocharger, intercooler and EGR valve to control the EGR mass flow rate.

Diethyl Ether (DEE) is a promising oxygenated renewable bio-base resource fuel used for diesel engines, owing to its high ignition quality. An experimental investigation has been carried out to evaluate the effects of DEE blends with diesel on the combustion, performance and emission characteristics of a direct injection diesel engine. The engine tests are carried out for 10%, 25%, 50%, 75% and 100% of the full load. In this study, 2%, 5%, 8%, 10%, 15%, 20% and 25% of DEE (by volume) are blended with diesel. Beyond 25% DEE blend, the viscosity and density of the blended fuel reduces as compared to the acceptable limits, that can further reduces the lubricity and create potential wear problems in sensitive fuel injection pump and fuel injector design. The laboratory fuel tests showed that DEE can be mixed in any proportion in diesel fuel. The blended fuel retains the desirable physical properties of diesel fuel but includes the cleaner burning capability of DEE.

Single cylinder and two cylinder diesel engines are having prevalent applications for as a source of power generation, three wheelers, agricultural machines, small house-hold applications as well as in mobile towers in India and other south Asian countries. As emission limits for these segment of engines are becoming stricter than the existing limits, it is necessary to upgrade these engines to meet the various emission limits applicable. The design features & technical characteristics of these engines are very simple and primitive, hence, it is extremely difficult and challenging to make these engines emission compliant. By using the relevant simulation tools, the task of emissionising these engines can be made simple to a greater extent. It gives a greater flexibility and ease in analyzing, designing, and operating complex engine systems.

As competent and low-pollution alternative fuel, CNG has revealed its excellence over engine performance and emissions. In recent years, CNG is considered as the diesel engine alternative fuel for heavy-duty engine applications due to its lower emissions and cost effective after-treatment systems. Due to the implementation of stricter emission norms over the years, the evolution of the fuel supply system has become more robust and electronically controlled. In the case of CNG engines, most of the engines were equipped with MPFI fuel system, for its precise fuel control abilities and controlling emission parameters. However, this MPFI system encompasses severe design changes in the intake manifold and is cost worthy to OEMs over the SPFI fuel system. MPFI system adds on the overall cost of the engine unit and its maintenance when compared to SPFI system.

Development of future efficient and cleaner heavy duty engines are no longer limited to laboratory development under standard conditions. In order to address the global issues like climate change and poor air quality in its true sense, future advanced and existing heavy duty diesel engines should also be demonstrating emission conformity compliance as per legislations under real driving conditions using PEMS testing. In India starting from Apr 2023, heavy duty vehicles would be tested for in-service conformity and presently they are under monitoring phase. With the introduction of RDE (Real Driving Emission) the effort, cost and time requirements could be tremendous in order to meet conformity compliance over real driving conditions including the range of ambient conditions for the said period as per the norms.

Diesel engines dominate in Heavy-Duty applications due to its better fuel economy, higher durability and larger reliability. Fuels derived from petroleum resources are depleting daily and it’s become a scarce resource for future generation to come. With growing environmental consciousness of the adverse implications brought by excessive usage of fossil fuels, the battle for finding alternative fuels as their substitution is getting heated up. At present, renewable energy from bio-fuels has been peddled as one of the most promising substitution for petroleum derived diesel. Using bio-ethanol blended diesel fuel for automobile can significantly reduce diesel usage and exhaust greenhouse gases. Bio-ethanol can be produced by alcoholic fermentation of sucrose or simple sugars. The main drawback is that ethanol is immiscible with diesel fuel over a wide range of temperatures, and the hygroscopic nature of ethanol leading to phase separation in blend.

In India, B7 (a biodiesel mix of 7% by volume in diesel) has been approved for use in diesel engines. Due to the depletion of fossil fuel supplies and tight pollution requirements, alternative diesel fuel has become critical. However, given the properties of diesel, no direct renewable alternative fuel can totally replace diesel. As a result, one of the solutions may be to replace part of the diesel with ethanol. In this inquisition, the impact of various diesel-ethanol blends, counting ED7.7, ED10, ED15 and ED20, were examined on two in-use multi-cylinder engines complying to different emission norms. The two engines under consideration complies with CPCB-I and CPCB-II, which is an Indian legal requirement for stationary Genset engines. For both engines, a 5-mode steady-state test cycle was considered. For each mode, the engine’s performance characteristics, including power, torque, and BSFC, were tested and described.

Currently, on-road transport contributes nearly 12% of India’s total energy related carbon dioxide (CO2) emissions that are expected to be doubled by 2040. Following the global trends of increasingly stringent greenhouse gas emissions (GHG) and criteria emissions, India will likely impose equivalent Bharat Stage (BS) regulations mandating simultaneous reduction in CO2 emissions and nearly 90% lower nitrogen oxides (NOx) from the current BS-VI levels. Consequently, Indian automakers would likely face tremendous challenges in meeting such emission reduction requirements while balancing performance and the total cost of ownership (TCO) trade-offs. Therefore, it is conceivable that cost-effective system improvements for the existing internal combustion engine (ICE) powertrains would be of high strategic importance for the automakers.

Following global trends of increasingly stringent greenhouse gas (GHG) and criteria pollutant regulations, India will likely introduce within the next decade equivalent Bharat Stage (BS) regulations for Diesel engines requiring simultaneous reduction in CO2 emissions and up to 90% reduction in NOx emission from current BS-VI levels. Consequently, automakers are likely to face tremendous challenges in meeting such emission reduction requirements while maintaining performance and vehicle total cost of ownership (TCO), especially in the Indian market, which has experienced significant tightening of emission regulation during the past decade. Therefore, it is conceivable that cost effective approaches for improving existing diesel engines platforms for future regulations would be of high strategic importance for automakers.