热力管网管损原因数值模拟分析

Numerical Simulation Analysis of Causes of Mass Loss in Heat Supply Networks

湖北某热力有限公司开发区热力管网由原“高参数”改为“低参数”运行,出现了管损过大的问题,剖析管损根源有非常重要的意义,利用湿蒸汽模型对该问题进行了数值模拟研究。首先,按原设计的“高参数”对其中的管段进行了校核,模拟中未出现蒸汽冷凝现象,计算值与原设计值接近。其次,对“低参数”运行进行了模拟,结果显示,阻力比原设计增加25%,在干管中发生了蒸汽冷凝,发现了蒸汽管道非平衡冷凝“回温”特征,这个研究结果也与有关文献公布的实际测试吻合。阻力增加是管损过大的原因之一,蒸汽干管出现冷凝,增加了疏水损失,这是管损过大的第二个原因。建议采用“高参数”供汽方案对管网实施改造。

A heat power in Hubei limited the heat pipe network from the original"high parameter"to"low parameter"operation,resulting in a problem that the mass loss was too large,so it has very important significance to analyze the root cause.The problem was studied by numerical simulation using the wet steam model,in which the pipe sections were calibrated according to the"high parameter"of the original design,and there was no steam condensation in the simulation,and the calculated values were close to the original design values.On the other hand,the results of the simulation of the"low parameter"opera⁃tion showed that the resistance increased by 25%compared to the original design,and steam condensation occurred in the dry pipe,and the characteristics of"rewarming"of nonequilibrium condensation of the steam pipeline was found,which is consistent with actual test results published in the relevant literature.Increased resistance is one of the reasons for the mass loss,and increased hydrophobic loss due to condensation in the steam trunk is the second reason.Based on the results of the analysis,it is recommended that a"high pa⁃rameter"steam supply program be used to modify the pipe network.