天然气锅炉余热深度回收换热器换热特性研究

Influence of Flue Study on the Characteristics of Heat Exchange of Waste Heat Recovery of Natural Gas Boiler

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费的问题,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。

In order to study the temperature distribution of the turbo-generator stator,a air-cooling 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.