百万千瓦二次再热机组再热蒸汽系统压力损失系数的分析研究

Analysis and Research of Reheat Steam System Pressure Loss Factor for 1000MW Double Reheat Thermal Power Plant

GB50660-2011《大中型火力发电厂设计规范》推荐的超超临界机组再热蒸汽系统压力损失系数为7%～9%,但二次再热机组的再热系统压力损失系数的取值范围值得进一步分析研究。根据设计参数选取了一系列不同直径、壁厚的管道规格,利用AFT流体分析软件对某百万千瓦二次再热机组再热蒸汽系统的压力损失进行了模拟计算,并依据汽轮机入口压力对热耗的影响,对管道投资和收益进行经济性对比分析。对于百万千瓦二次再热机组而言,一级再热系统的压力损失系数宜为6.7%～7.0%,二级再热系统的压力损失系数宜为8.29%～9.13%。

The advised reheat steam system pressure loss coefficient of ultra-supercritical unit is 7% to 9% by Code for Design of Fossil Fired Power Plant GB50660-2011, which is worth to be further studied for double reheat thermal power plant. The reheat steam system pressure loss of one 1000 MW double reheat thermal power plant was simulated by AFT fluid analysis software based on a series of pipes with different diameter and wall thickness selected by design parameters. Then the initial investment and profit economy were calculated and compared according to the effect of steam turbine inlet pressure on heat consumption. For 1000 MW double reheat thermal power plant, the reasonable pressure loss coefficient is 6.7% to 7.0% for the first stage reheat steam system, and is 8.29% to 9.13% for the second stage reheat steam system.