The Numerical Simulation Of The Combustion And Heat Transfer In The Hearth Of Fuel-Oil Or Fuel-Gas Boiler By CFX

The paper attaches great importance on the study of the temperature field, velocity field of the boiler and variation of the density of releasing pollutants, such as nitrogen oxide, carbon dioxide etc. through numerical simulation of the oil boiler with different shell structure under different working situations.Through analysis and comparison in the distribution of temperature field and velocity field and the influences of the pollutants releasing under the condition of different velocity of entry air flow in the numerical simulation of oil boiler in different working situations, it shows that the more faster the air flow is, the more evener the distribution of the temperature field and the more wider the heated area inside the boiler, but the more smaller the flame filling proportion and the highest temperature value and the more lower the utilization ratio of the fuel; and in the meanwhile, the more faster the velocity of the mixture of smoke and air in the shell in favor of transmitting heat in respect of velocity field, and the more lower the density of nitrogen oxide with regard to the releasing pollutants.During the study of numerical simulation of pipe-water-cooling-wall oil boiler, place several pipe-water-cooling walls inside the oil boiler to watch the operational aspect, and the result shows that heat exchange inside the boiler goes on well, but combustion of the fuel is not complete and the partial temperature of the oil boiler gets a little higher which can result in thermal stress and should be improved.During the study of numerical simulation of membrane-type-water-cooling-wall oil boiler, under the same condition as that during the study of pipe-water-cooling-wall oil boiler, it turns out the former one has a better leakproofness and a higher heat utilization ratio in turn because of the increase of the heated area inside the boiler.In conclusion, the paper has got some practical analytical results in boiler design and has enriched the boiler study, and also has certain instructive meanings to resolve some practical engineering problems.