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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.

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.

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.

Particulate matter is one of the major pollutant responsible for deteriorating air quality, particularly in urban centers. Information on contributing sources with the share from different sources is a first and one of the important steps in controlling pollution. Diverse sources, anthropogenic as well as natural, like industries, transport, domestic burning, construction, wind-blown dust, road dust contribute to particulate matter pollution. Receptor modeling is a scientific method which is utilized for assessment of the contribution of various sources based on chemical characteristics of particulate matter sources and ambient air particulate matter. Representative data of fractions of various chemical species in the particulate matter from the different sources i.e. source fingerprint is an essential input for the receptor modeling approach.

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.

This paper discusses experimental outcome of port fuel injected engines operated on gasoline mode and LPG mode. Eight Passenger car PFI engines were tested by using computerized engine data acquisition and control system on gasoline mode and LPG mode. Objectives of this experimental study were 1) To establish generic performance trend for group of newly introduced gasoline/LPG passenger car bi-fuel engines in Indian market. This trend has been established. 2) To compare performance of one sample engine in gasoline and LPG mode. This performance has been compared from performance characteristics curves in both modes. 3) To establish methodology to compare and contrast the performance of various types of Gasoline/LPG passenger car engines. This methodology has been established for a group of engines. 4) To define new normalized figure of merit suitable for the performance comparison of passenger car engines. A parameter power per unit displacement has been defined.

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.

The paper deals with the simulation of a Light Commercial Vehicle (LCV) using vehicle performance algorithms. This method speeds up the product development process. Also by using these kind of methodology in vehicle simulation there is much noticeable reduction in cost of testing. The simulation model is used for parametric studies of the vehicle and also to attain objectives such as to optimize transmission ratio, full load acceleration, maximum tractive force, gradient performance, fuel consumption and the exhaust emission. In this case study, simulation model of a CNG, LCV is used to analyze the performances similar to that done in a chassis dynamometer. The simulation leads to the prediction and evaluation of various parameters such as fuel consumption, exhaust emissions, full load acceleration, gradient performance & maximum tractive effort for Indian Driving Cycle.

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.

CNG has long since been established as a front runner amongst other available alternative fuels. In India, its infrastructure and penetration far exceeds others. While other, more efficient alternatives are been researched, CNG has established itself in the market as the alternative fuel of choice for majority of Indians. CNG technology has evolved itself from the basic venturi system to the more efficient sequential injection system nowadays. While the efficiency of an engine using sequential injection CNG has increased, the inherent problem with respect to lower volumetric efficiency and hence less power still persists. Direct injection CNG technology is seen as the solution to this age old problem. In the older days, the lack of technological expertise in SI direct fuel injection provided a stumbling block for development of direct gas injection.

The desire for higher fuel economy, improved performance and driveability expectations of customers from engines are gradually increasing along with stringent emission regulations set by the government. Many original engine manufacturing companies are prompted to consider the application of higher function variable valve actuation mechanisms in their next generation vehicles as a solution. The VVA is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine. The VVA allows lift, duration or timing (in various combinations) of the intake and/or exhaust valves to be changed while the engine is in operation. Engine designers are prompted to consider Variable Valve Actuation (VVA) system because of the inherent compromises with fixed valve events. The major goal of a VVA engine is to control the amount of air inducted into the engine which is a direct measure of torque.

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.

Energy dispersive X-ray fluorescence (EDXRF) analysis have made it possible to conduct elemental analysis on a variety of fields, including those with environmental, automotive, geological, chemical, pharmaceutical, archaeology, and biological origins. The ability of EDXRF to deliver quick, non-destructive, and multi-elemental analytical findings with increased sensitivity is of great importance. It is a vital tool for quality control and quality assurance applications. Thus, EDXRF plays an important role to compare batch-to-batch products for meeting quality standards. This paper presents application of EDXRF as an effective tool for quick qualitative and quantitative evaluation of given samples.

Real Driving Emission (RDE) norms have changed the way vehicles are required to be calibrated and developed. This has moved the legislative requirements from predictable lab conditions to more realistic, real world conditions. Current Indian legislation allows certification for Heavy Duty (HD) applications on engine level and therefore decoupled from vehicle and the real world scenarios such as uncertainty and randomness in driver behavior, traffic conditions, road profiles, ambient conditions etc. which are not captured. Upcoming RDE legislation to be implemented in year 2023, has made it necessary to integrate engine with vehicle to consider the impact of various parameters on engine operating points and therefore on tail pipe emissions. This paper focusses upon the methodology developed using RDE cycle generator tool (RCG) for generating on-road parameters which influences the zone of engine operation and resulting emission levels.

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.

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.

The design and development of a hydrogen powered spark-ignition engine, aimed for installation on a vehicle for on-road application. The experiment was conducted at WOT (Wide Open Throttle) condition at a speed of 4000 rpm with an excess air-fuel ratio of 1.3, 1.5, 2.2, 2.5, 3, 3.75, and 4.0. The ignition timing was optimized for maximum torque at each value of the excess air ratio. The various parameters analyzed such as in-cylinder pressure, Pressure and Volume, Logarithm of Pressure and Volume, Mass fraction burned, Cummulative heat release, Net heat release, Rate of pressure rise, and Mean gas temperature. The results show that there is a profound effect of excess air-fuel ratio on the engine’s mean effective pressure, output power, Brake thermal efficiency, Volumetric efficiency, Brake specific fuel consumption, and NOx emissions. The peak cylinder pressure decreases with an increase in excess air-fuel ratio and NOx emissions are reduced due to reduced mean gas temperature.