Search Results

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.

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.

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.

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.

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.

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.

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.

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.

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.

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 project was undertaken with an objective to develop methodology by formulating set of procedures that would help in achieving the end goal. Once methodology is established, it paves way to optimize the end results more effectively which results in reduced lead time during product development. Methodology can either be based on pure experimental investigations or by simulations. Combination of mathematical and empirical approach is inherently followed in simulations, which helps in reducing the testing time and overall cost. Commercial vehicles (CV) have seen paradigm shift in the fuel consumption (FC) certification approaches, with an intention to align with 2016 Paris climate agreement. Use of simulation tool like VECTO for commercial vehicle FC certification has gained momentum in Europe. Overall experience gained in commercial vehicle FC simulation has motivated us to leverage the learnings for off-road applications like agricultural tractors.

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.

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.

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.

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.

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.

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.

Hydrogen internal combustion engines (H2ICE) offer a cost-effective solution to decarbonize transport by combining a lower carbon intensity fuel with mature and established internal combustion engine technology. While vehicles running with hydrogen have been demonstrated over the years, this fuel's physical and chemical properties require modifications and upgrades on the vehicle from an engine and system-level perspective. In addition, market-specific regulatory and economic factors can also constrain the realization of optimal hydrogen powertrain architectures. Therefore, this paper reviews the impact of hydrogen use on combustion, injection, air management, and after-treatment systems, indicating the different strategies used to enable effective H2ICE strategies from an efficiency, cost, and safety standpoint.

Researchers are under pressure to investigate and discover ways to improve the efficacy and reduce emissions from ICE due to the depletion of energy resources and the growing concern over global warming. Hydrogen is viewed as a promising fuel and has been investigated as a potential fuel in combustion because to several desirable qualities like carbon-less content and strong flammability limitations. When equated to other alternative fuels like LPG, CNG, LNG, etc., hydrogen has inimitable qualities because it lacks carbon, making it one of the promising alternatives fuels. In order to achieve zero CO2 emissions for traffic applications in the near future, hydrogen being an automotive fuel in ICE is a solution. The ICE powered by hydrogen is prepared for that. The actual drawbacks of using hydrogen in ICE generally are manufacturing, storage, and development of the requisite infrastructure. Hydrogen can be produced in its many forms.