增压锅炉过热器三维数值模拟及热偏差分析

NUMERICAL MODELING AND ANALYSIS OF THERMAL DEFLECTION FOR THE OVERHEATER OF SUPERCHARGE BOILER

本文选择简化的增压锅炉过热器整体模型作为计算区域,综合考虑过热器热力特性、水力特性和结构特性,给出合理的边界条件,利用FLUENT软件对过热器内部流场进行流动与传热的三维数值模拟,得到蒸汽质量流量、蒸汽密度、蒸汽焓值以及热偏差等参数的分布规律。简化的整体模型计算方法克服了大量弯曲长管束网格划分的难题,实现了过热器内流场的整体计算。计算结果和实际数据能够较好地吻合,较准确地反映出该锅炉的实际情况。为进一步确立过热器管束壁温分布规律提供理论基础。

Simplified modeling of overheater of supercharge boiler is selected as numerical region. Using FLUENT to numerically simulate the flow field of flowing and heat transfer inside of the overheater in three dimension, coupled with considering its property of heat, water power and structure, the regularity of distribution of stream mass flux, density and enthalpy. This method solves problem to set grids of large number of bend and long pipes, and the flow field as a whole can be computed well. The result of simulation can fit the data of experiments and the actual condition of the boiler can be reflected well. This paper also provides a groundwork of theory to research the regularity of distribution of wall temperature of pipes.