The Influence Of Natural Gas And Hydrogen Co-combustion With Diesel Fuel On Engine Exhaust Emissions And In-cylinder Gas Composition

Reduction of exhaust emissions is a major research task in diesel engine development in view of increasing concern regarding environmental protection and stringent exhaust gas regulations. Simultaneous reduction of NOx emissions and particulate matter is quite difficult due to the soot/NOx trade-off and is often accompanied by fuel consumption penalties. Towards this aim, automotive engineers have proposed various solutions, one of which is the use of alternative gaseous fuels as a supplement for the commercial liquid diesel fuel. This type of engine, which operates fuelled simultaneously with conventional diesel oil and gaseous fuel, is called “dual fuel” diesel engine. Among alternative gaseous fuels, natural gas is considered to be quite promising due to its low cost and its higher auto-ignition temperature compared to other gaseous fuels facilitating thus its use on existing diesel engines. Previous research studies revealed that natural gas/diesel engine operation results in deterioration of brake engine efficiency, CO and HC emissions compared to conventional diesel fuel operation. In attempt to curtail these negative effects, various theoretical and experimental studies were carried out examining the influence of various parameters such as pilot fuel quantity, diesel fuel injection timing advance and intake charge conditions on “dual fuel” engine performance characteristics and pollutant emissions. However, there are more to know about the proper combination of these engine parameters to attain the optimum results regarding reduction of CO and HC emissions without further deteriorating, if not improving, brake engine efficiency. Hence, in the present study, a theoretical investigation is conducted using an engine simulation model to examine the effect of the aforementioned parameters on performance and exhaust emissions of a natural gas/diesel engine. Predictions are produced for a high-speed natural gas/diesel engine performance characteristics and NO, CO and Soot emissions at diverse engine speeds and loads using a comprehensive two-zone combustion model. The main objective of this comparative assessment is to elaborate the relative impact of each one of the above mentioned parameters on engine performance characteristics and exhaust emissions. Furthermore, an endeavor is made to determine the optimum combinations of these engine operational parameters. The conclusions of this study may be proven to be considerably valuable for the application of this technology on existing DI diesel engines.

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Comparative Evaluation of the Effect of Intake Charge Temperature, Pilot Fuel Quantity and Injection Advance on Dual Fuel Compression Ignition Engine Performance Characteristics and Emitted Pollutants

Volume 3: Combustion Science and Engineering ◽

10.1115/imece2009-10435 ◽

2009 ◽

Cited By ~ 7

Author(s):

Roussos G. Papagiannakis ◽

Theodoros C. Zannis ◽

Elias A. Yfantis ◽

Dimitrios T. Hountalas

Keyword(s):

Diesel Engine ◽

Natural Gas ◽

Diesel Fuel ◽

Diesel Engines ◽

High Speed ◽

Engine Performance ◽

Exhaust Emissions ◽

Performance Characteristics ◽

Dual Fuel ◽

Pilot Fuel

The simultaneous reduction of nitrogen oxide emissions and particulate matter in a compression ignition environment is quite difficult due to the soot/NOx trade off and it is often accompanied by fuel consumption penalties. Thus, fuel reformulation is also essential for the curtailment of diesel pollutant emissions along with the optimization of combustion-related design factors and exhaust after-treatment equipment. Various solutions have been proposed for improving the combustion process of conventional diesel engines and reducing the exhaust emissions without making serious modifications on the engine, one of which is the use of natural gas as a supplement for the conventional diesel fuel (Dual Fuel Natural Gas/Diesel Engines). Natural gas is considered to be quite promising since its cost is relative lower compared to conventional fuels and it has high auto-ignition temperature compared to other gaseous fuels facilitating thus its use on future and existing fleet of small high speed direct injection diesel engines without serious modifications on their structure. Moreover, natural gas does not generate particulates when burned in engines. The most common natural gas/diesel operating mode is referred to as the Pilot Ignited Natural Gas Diesel Engine (P.I.N.G.D.E). Here, the primary fuel is natural gas that controls the engine power output, while the pilot diesel fuel injected near the end of the compression stroke autoignites and creates ignition sources for the surrounding gaseous fuel mixture to be burned. Previous research studies have shown that the main disadvantage of this dual fuel combustion is its negative impact on engine efficiency compared to the normal diesel operation, while carbon monoxide emissions are also increased. The specific engine operating mode, in comparison with conventional diesel fuel operation, suffers from low brake engine efficiency and high carbon monoxide (CO) emissions. The influence becomes more evident at part load conditions. Intake charge temperature, pilot fuel quantity and injection advance are some of the engine parameters which influence significantly the combustion mechanism inside the combustion chamber of a Pilot Ignited Natural Gas Diesel Engine. In order to be examined the effect of these parameters on performance and exhaust emissions of a natural gas/diesel engine a theoretical investigation has been conducted by using a numerical simulation. In order to be examined the effect of increased air inlet temperature combined with increased pilot fuel quantity and its injection timing on performance and exhaust emissions of a pilot ignited natural gas-diesel engine, a theoretical investigation has been conducted by using a comprehensive two-zone phenomenological model. The results concerning engine performance characteristics and NO, CO and Soot emissions for various engine operating conditions (i.e. load and engine speed), comes from the employment of a comprehensive two-zone phenomenological model which had been applied on a high-speed natural gas/diesel engine. The main objectives of this comparative assessment are to record and to comparatively evaluate the relative impact each one of the above mentioned parameters on engine performance characteristics and emitted pollutants. Furthermore, the present investigation deals with the determining of optimum combinations between the parameters referred before since at high engine load conditions, the simultaneous increase some of the specific parameters may lead in undesirable results about engine performance characteristics. The conclusions of the specific investigation will be extremely valuable for the application of this technology on existing DI diesel engines.

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HIGH-RESPONSE COMPLEX FOR ANALYZING DROPLETS AND VAPORS IN AEROSOL CLOUDS FORMED IN THE ATMOSPHEREDUE TO LIQUID DISPERSION

PROGRESS IN DETONATION RESEARCH ◽

10.30826/icpcd12a20 ◽

2020 ◽

Author(s):

A. V. ZAGNIT'KO ◽

◽

N. P. ZARETSKIY ◽

I. D. MATSUKOV ◽

V. V. PIMENOV ◽

...

Keyword(s):

Remote Control ◽

Natural Gas ◽

Diesel Fuel ◽

Liquefied Natural Gas ◽

High Response ◽

Liquid Dispersion ◽

Diagnostic Complex ◽

Response Complex

The high-response diagnostic complex for remote control and analyses of droplets and vapors of mazut, oil, gasoline, kerosene, diesel fuel and liquefied natural gas in the clouds and turbulent aerosolflows in the atmosphere with volume up to 107 m3 is described.

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