| This text is the buner's numerical simulation part of "study and application of production technology characteristic of new cement produced with the dry method of the high prototype",which is the sub subject of the national high-tech research (863 Program) "Industrialization and Key Preparation Technology of Low Environmental Impact Cement."(serial number of project: 2002AA335050)The performance research of burning device is a key of cement trade development as offering heat source to the device. But carrying on computer three-dimension visual artificial work have many questions that yet not received rational theory support, which caused manufacture and the burning device using of rotary kilns to be all at experience stage.Then it is the active demand that industrial development of cement saves energy and reduces the cost to carry on research to it through the Hi-Tech means.According to the actual burner geometry parameters, we use CFD commercial software of Fluent to do a numerical simulation of gas-solid flow and pulverized coal combustion in the kiln burner combustion.The purpose of subject research is to grasp hot simulation of structural parameter influencing regularity and pollute gas distribute which can decompose theoretical foundation to the newly systematic burning device when designed, thus achieve the goal of guiding the burning device at home to improve and industrialized production practices of this system.This text introduction used Gambit to do accurate three-dimension simulation for the structure of burning device. The result shows:The method when insert the law step by step and sinning law is a set of schemes optimizing complicated structural modeling.At the same time, to analyze result of swirl design and calculation parameter showed the burn have more characteristic of reflux area that proves its existence can improve burning rate of the coal powder and thermal efficiency. In the article according to imitate, fruit analysis form mechanism of the pollute and temperature field, velocity field, component field,etc when the structure operates.And compared with every parameter influence in the field of the structural design to get the best operation mode are as follow: swirl wind speed is 160m/s, direct current wind speed is 240m/s,velocity of coal mass flow is 0.97 m/s . And the angle of best swirl is 25 degrees, explained the characteristic with low pollutants and this structure can offer the burning of poor coal at the same time.The innovation herein is lighted and lain in:(1) At the first time we with Gambit model the complex burner structure. Therefore breakthrough exists in the precision modeling of burner, and the negative impact reduces the approximate numerical simulation modeling results.(2) Firstly successfully added chemical reactions to the coal combustion, avoided no discussion on composition, and make numerical simulation results more accurate. The result is very identical real condition of production. This has verified the feasibility that the numerical simulation employs in the cement trade too, and has offered the theoretical foundation for designing when using the CFD technology guides the burning device in the future.(3) The attempt employs CFD technology to compare different structure and parameter to imitate for the first time, and has analyzed to the result. All that is a breakthrough to the research in this respect on structure paraments. |
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