小型蒸汽锅炉水煤浆燃烧行为的数值模拟研究

Investigating coal-water slurry combustion in a small steam boiler through numerical simulation

为了将水煤浆燃烧技术应用于国内中小型锅炉的改造,本文是以Fluent17.0为计算平台,以国内某小型水煤浆蒸汽锅炉为研究对象,采用数值模拟方法研究了水煤浆在炉膛内的燃烧和传热特性。基于Gambit2.4建立了锅炉炉膛的三维物理模型,并以六面体结构网格对计算区域进行了网格划分。基于Fluent17.0,在充分考虑水煤浆的雾化特点和水汽化吸热的基础上,详细研究了助燃空气预热温度变化对炉内水煤浆燃烧、炉膛温度分布和水冷壁换热的影响。研究结果表明,当助燃空气预热温度为523K时,水煤浆可在该锅炉炉膛内实现良好的燃烧,且能量利用也能达到较高水平。

This paper utilizes Fluent 17.0 as the computational platform to study the combustion and heat transfer characteristics of coal-water slurry in a domestic small-scale steam boiler through numerical simulation methods.A threedimensional physical model of the boiler furnace was constructed using Gambit 2.4,and a hexahedral structured mesh was applied to the computational domain.Based on Fluent 17.0,and considering the atomization characteristics of coalwater slurry and the heat absorption of water vaporization,this study thoroughly investigates the effects of variations in the preheating temperature of combustion-supporting air on the combustion of coal-water slurry within the furnace,temperature distribution in the furnace,and heat transfer to the water-cooled walls.The results show that with the combustionsupporting air preheated to 753°C,coal-water slurry can achieve efficient combustion in this boiler furnace,also reaching a higher level of energy utilization.