Abstract:

This study established a heat transfer model for a multi-layer composite insulation structure applied to steam pipelines, conducting experiments on DN200mm pipelines to investigate the impact of various insulation structures and materials on insulation performance. The model's accuracy was validated against experimental data, facilitating the determination of the optimal insulation plan under diverse operating conditions. Experimental findings indicated that the pipe surface heat flow density decreased with the addition of convective layers and airbag layers, while it gradually diminished with increased shawl thickness and overall insulation thickness. However, an increase in reflective layers initially decreased and then increased the heat flow density. The heat transfer model predictions closely aligned with experimental data, showing a deviation of less than 6%. Economic analysis advised against using convective layer as insulation material. The recommended optimal insulation solution substantially reduced the system's total heating cost. The optimal insulation thickness value increased with the increase of the medium temperature and pipe diameter. Particularly for high-temperature pipelines exceeding 400℃, adopting composite insulation structures can yield over 30% savings compared to single aluminum silicate insulation.

Key words: heat transfer, composite insulation structure, optimal insulation solution, economic analysis

摘要：

建立了蒸汽管道多层复合保温结构传热模型，采用DN200mm管道实验研究了不同保温结构和保温材料对隔热性能的影响，根据实验数据验证了数学模型准确性，并以此为基础给出了不同工况下最佳保温方案的确定方法。实验结果显示，管道表面热流密度随着对流层的加入和气囊层数的增加而降低，随披肩厚度和保温总厚度的增加逐渐降低，而反射层数量增加热流密度先降低后升高。传热模型预测结果与实验数据高度吻合，相差不到6%。从经济性分析，不宜采用对流层作为保温材料。最终确定的最佳保温方案能够显著降低系统的供热总成本，最优保温厚度值随管内介质温度和管径的增加而升高。对于温度大于400℃的高温管道，采用复合保温结构相比于单一硅酸铝保温可节省超过30%的投资。

关键词: 传热, 复合保温结构, 最优保温方案, 经济性分析