Integration of an Energy Storage in Connection with the Combustion Chamber of a Diesel Engine to Reduce the NOx Emission

The assembly consistency of a diesel engine will affect its nitrogen oxides (NOx) emission variation. In order to improve the NOx emissions of diesel engines, a study was carried out based on the assembly tolerance variation of the diesel engine’s combustion system. Firstly, a diesel engine which meets the Euro VI standards together with the experimental data is obtained. The mesh model and combustion model of the engine combustion system are built in the Converge software (version 2.4, Tecplot, Bellevue, DC, USA), and the experimental data is used to calibrate the combustion model obtained in the Converge software. Then, the four-factor and three-level orthogonal simulation experiments are carried out on the dimension parameters that include nozzle extension height, throat diameter, shrinkage diameter and combustion chamber depth. Through mathematical analysis on the experimental data, the results show that the variation of nozzle extension height and combustion chamber depth have a strong influence on NOx emission results, and the variation of combustion chamber diameter also has a weak influence on NOx production. According to the regression model obtained from the analysis, there is a quadratic function relating the nozzle extension height and NOx emissions and the amount of NOx increases with increasing nozzle extension height. The relationship between emission performance and size parameters is complex. In the selected size range, the influence of the variation of the chamber diameter on NOx is linear. The variation of the chamber depth also has an effect on NOx production, and the simulation results vary with the change of assembly tolerance variation. Thus, in the engine assembly process, it is necessary to strictly control the nozzle extension height and combustion chamber depth. The research results are useful to improve the NOx emission of diesel engine and provide a basis for the control strategy of selective catalytic reduction (SCR) devices.

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Experimental Study on Emissions of Hydrogen Enriched Diesel Engine With Varied Combustion Chamber Geometry

Volume 1: Biofuels, Hydrogen, Syngas, and Alternate Fuels; CHP and Hybrid Power and Energy Systems; Concentrating Solar Power; Energy Storage; Environmental, Economic, and Policy Considerations of Advanced Energy Systems; Geothermal, Ocean, and Emerging Energy Technologies; Photovoltaics; Posters; Solar Chemistry; Sustainable Building Energy Systems; Sustainable Infrastructure and Transportation; Thermodynamic Analysis of Energy Systems; Wind Energy Systems and Technologies ◽

10.1115/es2016-59164 ◽

2016 ◽

Author(s):

Jyothi Us ◽

K. Vijaya Kumar Reddy

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Flow Rate ◽

Internal Combustion Engines ◽

Fossil Fuels ◽

Nox Emission ◽

Emission Characteristics ◽

Oxides Of Nitrogen ◽

Piston Bowl ◽

Combustion Properties

The depletion of fossil fuels and its emissions promoted the researchers to search for substitute fuels and their controlled combustion. Hydrogen is considered as one of the best fuels for internal combustion engines because of its unique combustion properties. Currently, there are very few commercial devices that utilize hydrogen combustion for the production of heat, which is mainly due to the limited availability of hydrogen fuel. As the accompanying environmental legislation will clearly favour clean technologies, the emergence of hydrogen as an energy carrier will modify this situation. To achieve controlled combustion, an attempt was made at investigating the effect of change of piston geometry on the emission characteristics of diesel engine enriched with hydrogen at optimum flow rate. Experiments were conducted to study the effect of varied piston bowl geometry on the emission characteristics of diesel engine enriched with hydrogen at a flow rate of 6 lpm on four stroke single cylinder diesel engine at constant speed of 1500 rpm for different loads. For flow rates above 6 lpm knocking tendency was observed due to raise in temperature and peak pressures with addition of hydrogen. The experiments were conducted with standard hemispherical, toroidal and re-entrant toroidal piston bowl geometry at 6 lpm flow rate of hydrogen duly ensuring the same compression ratio in all three cases. The emissions for diesel engine enriched with hydrogen in hemispherical combustion chamber at 6 lpm flow rate were reduced by 27.1%, 37.5% and 10.8% of unburnt hydrocarbons (UHC), Carbon monoxide (CO) and smoke density respectively when compared to diesel fuel alone operation at rated load. This is mainly due to high combustion temperatures which lead to complete burning of fuel and reduction in carbon content with addition of hydrogen. However, there was a 14% increase in oxides of Nitrogen (NOx) emission due to high combustion temperatures by hydrogen induction. With toroidal and reentrant geometry of the combustion chambers at 6 lpm flow rate of hydrogen, the emission parameters were further reduced notably. Further there is an increase in NOx emission was observed in dual fuel mode compared to standard piston due to high cylinder temperatures and pressures. The obtained results show that at part load conditions with enriched hydrogen, the percentage reduction of NOx emission was engine load dependent, being least increase at low loads and high increase at high loads. The reduction in emission particulates with varied combustion chamber bowl geometry was due to improved swirl motion of high turbulence of air in the combustion.

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NOx Reduction of a Medium Speed Diesel Engine Using a Charge Air Moisturizer System

ASME 2006 Internal Combustion Engine Division Fall Technical Conference (ICEF2006) ◽

10.1115/icef2006-1548 ◽

2006 ◽

Cited By ~ 3

Author(s):

Hyoung-Keun Park ◽

Sang-Hak Ghal ◽

Byong-Seok Kim ◽

Ki-Doo Kim ◽

Jong-Suk Kim

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Nox Reduction ◽

Water Injection ◽

Combustion Process ◽

Hot Water ◽

Nox Emission ◽

Injection System ◽

Medium Speed ◽

A Charge

It is well known that water can be used to prevent NOx formation during a combustion process. It is based on the principle by decreasing flame temperature with increasing the specific heat capacity of combustion air by adding water to a combustion chamber. Introducing water into a charge air enables much more water addition into a combustion chamber than other methods, which can reduce NOx emission to lower level than the others. The method has also the advantage of low installation cost. In a general water injection system for a charge air only hot water is sprayed into the charge air and vaporized, but more effective means to introduce water into the charge air is needed because only small amount of water is evaporated in hot water injection system. In this study, steam and hot moisturizing water are injected simultaneously. The steam supplies steady additional energy for evaporation of the water and can be vapor by itself. The new method was evaluated for NOx reduction performance on a medium speed diesel engine. NOx emission was reduced to 10∼38% on the 27∼59gram water per kilogram dry air.

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