秦柏　张强　张波　吴超

摘要：针对在天然气锅炉中，由于排烟温度较高，排烟热损失相对较大，过热状态的水蒸气随排烟到大气中造成水蒸气潜热的巨大浪費的问题，根据工程热力学和计算传热学相关理论，在天然气锅炉系统尾部加装翅片管换热器用来回收排烟过程中烟气的显热和水蒸气凝结时释放的潜热，用此来进行余热的深度回收。进一步通过数值模拟的方法，来研究烟气侧入口速度对翅片管换热器换热特性的影响，得出了入口速度在一定范围内，速度越大换热效果越好。从而合理选择烟气侧入口速度，为深度回收烟气热量提供理论依据。

关键词：

余热回收；烟气入口速度；换热特性；数值模拟

DOI：10.15938/j.jhust.2018.05.004

中图分类号： TK11

文献标志码： A

文章编号： 1007-2683（2018）05-0021-04

Abstract：In order to study the temperature distribution of the turbogenerator stator ，a aircooling Aiming at the problem that there is a huge loss of latent heat in water vapor caused by the high exhaust gas temperature in the natural gas boiler， relatively large exhaust heat loss and water vapor in a superheated state going into the atmosphere， based on relevant theories of engineering thermodynamics and heat transfer calculation， a finned tube exchanger is added to the natural gas boiler system to deeply recycle the sensible heat of flue gas in the gas extraction process and the latent heat released during the steam condensation process in order to recover the waste heat Based on this， the paper carries out a study on the influence of inlet velocity on the heat transfer performance of finned tube heat exchanger and through numerical simulation draws the conclusion that within a certain scope of inlet velocity， the heat transfer efficiency is better along with higher speed so as to select reasonable flue gas inlet velocity to achieve the goal of reducing the exhaust gas temperature， recovering deeply the flue gas heat

Keywords：waste heat recovery；the flue gas inlet velocity ；heat transferperformance；numerical simulation

0引言

人类文明社会的快速进步和创新型能源的不断涌现，能源的消耗量及消耗形式也发生了与时俱进的变化。传统锅炉，由于排烟温度较高，将会有大量水蒸气得不到回收，造成水蒸气潜热的巨大浪费[1]。

针对天然气锅炉排烟温度较高，回收过热状态下水蒸气的潜热难的问题，本文采用翅片管换热器回收烟气余热，文[2-4]中用实验的方法研究了螺旋翅片管束的排列方式对管束换热特性和流阻特性的影响，根据实验结果拟合得到传热系数和阻力系数的关系式，为翅片管换热器的设计提供理论支持和改进依据。翅片管换热器拥有良好的传热性能，采用翅片管换热器回收烟气余热，可以降低排烟温度，同时还可以回收温降过程中的显热和水蒸气冷凝时释放的相变潜热，提升锅炉的热效率[5]。……