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 ...

The development of combustion systems to minimize the emission of pollutants and to increase the system’s efficiency involves modifications of the combustion process using premixed systems and highly turbulent swirl stabilized flames. However, these modifications of the combustion process usually lead to stability problems caused by the appearance of combustion-driven oscillations. Therefore, i...

The objective of this study is to investigate the combustion in a pilot-ignited supercharged dual-fuel engine, fueled with different types of gaseous fuels under various equivalence ratios. It is found that if certain operating conditions are maintained, conventional dual-fuel engine combustion mode can be transformed to the combustion mode with the two-stage heat release. This mode of combusti...

Gasoline compression ignition (GCI) has been shown as one of the advanced combustion concepts that could potentially provide a pathway to achieve cleaner and more efficient combustion engines. Fuel and air in GCI are not fully premixed compared to homogeneous charge compression ignition (HCCI), which is a completely kinetic-controlled combustion system. Therefore, the combustion phasing can be ...

Modern combustion devices are designed to balance the need for efficient performance with the need for robust performance. Presently available design techniques are capable of meaningfully informing how this balance should be struck. To truly optimize the efficiency and robustness of a combustor, however, the predictive capabilities of numerical simulations will have to be more heavily relied u...

The combustion characteristics of both pure propane hydrates and the mixtures of hydrates and quartz sands were investigated by combustion experiments. The flame propagation, flame appearance, burning time and temperature in different hydrate layers were studied. For pure propane hydrate combustion, the initial flame falls in the “premixed” category. The flame propagates very rapidly, mainly as...

Hypersonic air-breathing engines rely on scramjet combustion processes, which involvehigh speed, compressible, and highly turbulent flows. The combustion environment andthe turbulent flames at the heart of these engines are difficult to simulate and study in thelaboratory under well controlled conditions. Typically, wind-tunnel testing is performedthat more closely approximates ...

porous media has interesting features in compared with free flame combustion due to the extended of the lean flammability limits and lower emissions. advanced new generation of internal combustion (ic) engines are expected to have far better emissions levels both gaseous and particulate matter, at the same time having far lower fuel consumption on a wide range of operating condition. these crit...