【摘要】 本文针对工业烟气不洁净的特点及常见换热器污垢热阻与清灰效果相互制约的问题,提出了一种高效、低阻及清灰效果好的蜂巢式烟气换热器。首先,基于所建立的积灰预测模型,获得了蜂巢式换热表面的积灰分布及形貌;接着,基于搭建的换热元件积灰特性在线测试平台,实验研究了蜂巢式换热表面的积灰和换热特性。结果表明,本文建立的积灰预测方法能够很好地预测蜂巢式换热表面的积灰及换热特性;最后,分析了横向节距和纵向节距对蜂巢式换热器积灰特性及积灰后换热和阻力特性的影响规律,拟合了积灰状态下污垢热阻渐近值的关联式,所有数据点的相对偏差不超过4%,有助于蜂巢布置换热器的工程应用。更多还原

【Abstract】 A honeycomb flue gas heat exchanger with high efficiency,low resistance and good cleaning effect was proposed to solve the mutual constraint problem of fouling thermal resistance and soot-blowing effect in flue gas heat exchangers.Firstly,the fouling distribution and morphology of honeycomb heat transfer surface were obtained based on the established fouling prediction model.Then,based on the built online experiment system for fouling characteristics of heat exchange elements,the fouling and heat transfer characteristics of honeycomb heat exchanger were studied experimentally.The results show that the fouling prediction method established in this paper can well predict the fouling and heat transfer characteristics of flue gas heat exchangers.Finally,effects of tube pitches on the fouling and thermal-hydraulic characteristics of the honeycomb heat exchanger were examined parametrically,and the correction of fouling thermal resistance was fitted to facilitate engineering applications.更多还原