数值模拟在锅炉安全运行中的应用

Application of Numerical Simulation Methods to the Boiler's Safe Operation

四角切圆燃烧锅炉在运行中遇到的诸多问题如炉膛结渣、水冷壁爆管、过热器区域的左、右温度偏差、燃烧稳定性等均与炉膛温度分布密不可分。炉膛温度分布是否合理,炉膛配风至关重要。炉膛配风若不合理,严重影响锅炉的安全运行。炉膛的配风调整十分复杂,通过空气动力场试验获得的数据比较有限,同时需要花费大量的人力物力。以元宝山电厂3号炉为例,利用应用软件GAMBIT和FLU-ENT,模拟切圆燃烧锅炉的配风。通过模拟不同工况下炉内配风,分析不同工况下炉内空气动力场,得到一二次风的最佳配比,获得良好的炉内动力场分布。数值模拟为锅炉的安全运行提供参考的数据,为优化锅炉的安全经济运行提供参考方案,同时节约大量的人力物力,数值模拟在锅炉安全运行中必将会得到广泛的应用。

The problems occurring in the operation of a tangentiaUy fired boiler, such as slag, water-wall tube failure, the thermal imbalance of the overheater, and combustion stability, are closely connected with the temperature distribution in the furnace. The air distribution is a key to the temperature distribution. However, controlling the air distribution is very difficult, and the aerodynamic field trials can only offer limited data. This paper simulates the air distribution of a tangentially fired boiler by using the software ＂GAMBIT＂ and ＂FLUENT＂. Taking the 3^# boiler in the Yuanbaoshan Power Plant as an example, the optimal compounding of the primary and second airs is obtained by the simulation and the optimized air field can be obtained by analyzing the air distribution of the tangentially fired boiler under different conditions. Numerical simulation can be used for providing reference data and reference operation plans for safe operation of boilers. Numerical simulation methods would be extensively applied to boiler operations in the future.