سوخت و احتراق

سوخت و احتراق

A Computational Study of the Effects of Combustion Chamber Geometries on Combustion Process and Emission in a DI Diesel Engine

نویسندگان
صمد جعفرمدار
مجتبی خباز زاده
گروه مهندسی مکانیک، دانشکده فنی، دانشگاه ارومیه،ایران
چکیده
A computational study aiming to investigate the effect of combustion chamber geometry on combustion process and emission has been carried out in a direct injection diesel engine. The combustion process and emission of three different combustion chamber geometries were considered, and combustion process behaviors such as variation of mean pressure, velocity, heat release rate, emission production and flame movement were revealed. The results also proved that the chamber shape has significant effects on the combustion and emission behaviors. They also showed that reentrant combustion chamber released less Soot and NOx emissions because of intense swirl, tumble and low temperature combustion. Also it was known that depth of chamber is an effective parameter on NOx and soot formation. The results of this model for cylindrical combustion chamber geometry were compared with the corresponding experimental data and proved to be good agreement. Generally it was found that the shape of Omega is the best selection for piston head, but it strongly needs strongly to match chamber geometry with spray characteristics.

تازه های تحقیق

This study has revealed that flame behavior is strongly dependent on combustion chamber geometry. The reentrant chamber prevents the flame from spreading over the squish region and fast mixing, makes a great reduction in exhaust soot by increasing swirl and tumble. Also because of the low temperature in the cylinder, the chamber is confirmed from NOx viewpoint. The result of this model for the NOx emission and pressure cylinder at the cylindrical combustion chamber are compared with the corresponding experimental data, and prove to be in good agreement. But it should be noticed that the nozzle position is in strict relation with soot production. Combustion chamber optimization is not sufficient by itself and accurate optimization in injector position by combustion chamber is needed to have a large reduction in emissions.

 

کلیدواژه‌ها
chamber geometry
Modeling
Emission
combustion process
Swirl
tumble

عنوان مقاله English

A Computational Study of the Effects of Combustion Chamber Geometries on Combustion Process and Emission in a DI Diesel Engine

نویسندگان English

Samad Jafarmadar
Mojtaba Khanbabazadeh
Department of Mechanical Engineering, Faculty of Engineering, Urmia University, Iran
چکیده English

process and emission has been carried out in a direct injection diesel engine. The combustion process and emission of three different combustion chamber geometries were considered, and combustion process behaviors such as variation of mean pressure, velocity, heat release rate, emission production and flame movement were revealed. The results also proved that the chamber shape has significant effects on the combustion and emission behaviors. They also showed that reentrant combustion chamber released less Soot and NOx emissions because of intense swirl, tumble and low temperature combustion. Also it was known that depth of chamber is an effective parameter on NOx and soot formation. The results of this model for cylindrical combustion chamber geometry were compared with the corresponding experimental data and proved to be good agreement. Generally it was found that the shape of Omega is the best selection for piston head, but it strongly needs strongly to match chamber geometry with spray characteristics.

کلیدواژه‌ها English

: chamber geometry
modeling
emission
combustion process
swirl
tumble
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