homogenous charge compression ignition (hcci) combustion is spontaneous multi-site combustion of a nominally premixed air/fuel mixture that exhibits high rate of pressure rise and short combustion duration. to avoid excessive pressure rise rate and knocking, hcci engines are fueled with highly diluted mixture using a combination of excess air and/or egr. hcci combustion is attractive due to ext...

Combustion mechanism of a 300 MW pulverized coal boiler is analyzed and the optimization of the performance of the boiler is carried out. The flow field, temperature field, devolatilization, char combustion and CO generation in the boiler furnace under actual condition is obtained by using Fluent. Three methods to improve the efficiency of boiler combustion are proposed based on the pulverized ...

In this paper, the effect of adding hydrogen to the composition of methane and air in a micro combustor is investigated by a three-dimensional numerical method. First, the results of the current study in determining the wall temperature of the micro combustion chamber are compared with those obtained from the experimental and numerical results of the previous research. By confirming the numeric...

This paper reports a comparative study of burning Thai rice husk, sunflower shells and fine rubberwood sawdust as well as co-firing of the sawdust and shredded eucalyptus bark in the swirling fluidizedbed combustor (SFBC). All experiments for firing individual fuels were performed for the combustor heat input of ∼300 kWth. However, in the co-firing tests, the fuel mixture was delivered at a fix...

The formation of thermal NO and fuel type NO emission under the air staged combustion in a tower pulverized coal fired boiler that burners are arranged in the front and the rear wall are investigated in this paper. Effects of the distribution of oxygen in the main combustion zone on NOx are then analyze qualitatively. The results show that when the SOFA ratio is 34.98%, NOx yield is at the mini...

Diesel and biodiesel spray combustion in a high temperature and high pressure environment was investigated in a constant volume combustion chamber. The effects of ambient gas temperature and ambient oxygen concentration on the combustion process were studied. The ambient temperatures varied from 800 K to 1200K, while the ambient oxygen concentrations varied from 21% to 9%. The results indicate ...

In view of the economy and environmental impacts of the energy utilization, most of the heat transfer industries such as steel mills, glass plants and forging shops, foundry process and furnaces are focusing on energy efficient strategies and implementing new technologies. Gas Technology Institute (GTI) and Air Liquide Chicago Research Centre (ALCRC) have applied Oscillating Combustion Technolo...

In order to lower the Nitrogen Oxides (NOx) concentration in internal combustion engine emissions and to improve performance, Exhaust Gas Recirculation (EGR) and Scavenging mechanism are introduced. EGR recirculates a fraction of the exhaust gas back into the cylinders, thus diluting the intake air. This lowers the maximum combustion temperature and, since the formation of NOx is heavily depend...

In internal combustion engines, exhaust valve and its seat gain considerable temperature as the hot gases exit through them. So, the rate of heat transfer should be under control. In this study, the contact heat transfer coefficient has been estimated. An experimental study on an Air-Cooled internal combustion engine cylinder head has been considered. Using the measured temperatures of sensors ...