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Showing 1 to 13 of 13 for “"Natural gas engine"”.
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Nitric oxide conversion in a spark-ignited natural gas engine
A large percentage of stationary engine applications are natural gas fueled. The cleanest of these large bore engines currently produce on the order of one gram of NOx per brake-horsepower hour (g/bhp-hr) of work done. The goal of this work is to reduce these emissions to 0.1 g/bhp-hr levels. …
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Optimizing power cylinder lubrication on a large bore natural gas engine
… integral compressors, located along America's natural gas pipelines, pump natural gas across the United States. These compressors are powered by 2-stroke, large bore natural gas burning engines. Lowering the operating costs, reducing the emissions, and ensuring that these engines remain …
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Reduction of natural gas engine emissions using a novel aftertreatment system
… an exhaust aftertreatment system to reduce gaseous and particulate matter emissions from natural gas fueled vehicles. Specific objectives of this study were to evaluate and characterize emissions from a natural gas fueled vehicle powered by a Cummins C8.3G+ engine with and without the …
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Computational fluid dynamics modeling of a large bore two-stroke natural gas engine
Natural gas fueled engines have been used for many years in stationary applications such as gas compression and electric power generation. In the United States alone, there are over 8,000 large bore (bore >30 cm) slow speed (speed < 500 rpm) natural gas engines in use. The most common configuration …
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Oxidation catalyst degradation in the exhaust stream of a large bore 2-stroke natural gas engine
Lean burn 2-stroke natural gas engines are commonly used for power generation and gas compression. These engines, however, contribute to air pollution primarily through emissions of carbon monoxide, volatile organic compounds and some unburned hydrocarbons. Oxidation catalysts aid in reducing these …
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Diluted Operation of a Heavy-Duty Natural Gas Engine - Aiming at Improved Effciency, Emission and Maximum Load
Most heavy-duty engines are diesel operated. Severe emission regulations, high fuel prices, high technology costs (e.g. catalysts, fuel injection systems) and unsustainably in supplying fuel are enough reasons to convenience engine developers to explore alternative technologies or fuels. Using …
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An Experimental Investigation of the Injection Process in a Direct-Injected Natural Gas Engine Using PLIF and CARS
A set of scaling factors derived from the conservation equations effectively collapsed fuel jet penetration measurements under both motoring and stationary piston conditions. The scaling factors are based on the pseudo diameter of the jet, which is the diameter of an equivalent sonic jet expanded …
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Evaluation of advanced air-fuel ratio control strategies and their effects on three-way catalysts in a stoichiometric, spark ignited, natural gas engine
Engine emissions are a growing concern in the 21st century. As the world works to combat rising pollution levels, engine emissions are under scrutiny. Natural gas engines are increasing in popularity over diesel engines, due to the high availability of fuel and fewer pollutant emissions than …
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Reducing emissions of a large bore two stroke cycle engine using a natural gas and hydrogen mixture
… combustion temperatures. A challenge for engine researchers is to identify methods to lower combustion temperatures while maintaining complete combustion. Blending hydrogen into an engine's fuel can lower in-cylinder combustion temperatures and reduce pollutant emissions. Hydrogen has a …
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The catalytic reduction of emissions from a natural gas fueled spark ignited engine
Activity in converting gasoline engines to operate on natural gas has increased in recent years due to the passage of The Clean Air Act of 1990 and The National Energy Policy in 1992 (EP ACT). Both policies require companies with large vehicle fleets to purchase a number of alternatively fueled …
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Selective catalytic reduction: testing, numeric modeling, and control strategies
… was installed on a Cooper Bessemer GMV-4 natural gas engine. Transient data was taken of commercially available SCR Catalysts. These transient tests are used to quantify SCR catalyst response. Space velocity, catalyst temperature, inlet NOx concentration, and ammonia to NOx molar feed …
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Fundamental studies of flame propagation in lean-burn natural gas engines
<p>Lean-burn natural gas engines offer enhanced thermal efficiencies and reduced soot and NOx emissions. However, cycle-to-cycle variability in combustion that can result from unreliable ignition, variability in equivalence ratio and quenching is a challenge. Reliability of ignition can be improved …