The Simulating Of Gas Combustion In Tunnul Kiln

Tunnel kiln is expensively applied in the process of making inorganic non-metal materials. It often consists of preheating zone, burning zone and cooling zone. The structure, burning setup and arts parameters decide how to acquire the profitable temperature system and atmosphere system. At the same time, they also affect the temperature uniformity and NOx outputs out of tunnel kiln. If the structure setups and function parameters are irrational, there will lead to the following results: prolonging the burning period, reducing the quality of the products, reducing the utilization of energy sources, sharpening environment pollutions and affecting the economy benefits and social benefits seriously.By the numerical simulation of tunnel kiln, we can optimize the structure of tunnel kiln, burning setup and burning arts and crafts parameters, which provide the theoretic foundation for designing the kiln and controlling them.We set up the models and mesh the models with Tet/Hybrid grids.according to the real structure of the tunnel kiln. By using the computer numerical simulation and the standard k-εmodel of a CFD software, we simulate the distribution of temperature uniformity and NOx output on the different conditions. We analyse how the changes of burning setups and arts parameters affect the temperature uniformity and NOx output.The results show that:(1)As the excess air coefficient augments, the temperature reduces and the temperature uniformity improves on the conditions of the same parameters. (2)The excess air coefficients have a notable effect on NO outputs. The NO outputs are relative to the concentration and temperature of oxygen. When the excess air coefficient is 1.1, the output of NO reaches the maximum; (3) When the nozzle is in the position lack of symmetry, the temperature uniformity is good and the NO outputs is high too. On the contray, when the nozzle is in the symmetry position, the temperature uniformity is bad and the NO outputs are low too.