Heat exchangers for residual heat recovery in coal-fired power plants face the issues of low heat transfer efficiency of flue gas side and the fly ash fouling. However, heat transfer enhancement structures always increase the fouling on the fin. Efficient methods are required to improve both heat transfer and anti-fouling performance of the heat exchanger. In present study, the thermal-hydraulic and anti-fouling performances of enhanced double H-type finned tubes are numerically investigated using the discrete phase model coupled with particle deposition and removal model. Five types of double H-type finned tubes with different layouts of grooves and longitudinal vortex generators (LVGs) are investigated to improve both thermal-hydraulic and anti-fouling performance of fin. The effects of particle diameter, flue gas velocity and layout of enhanced structures are discussed. It is found that the transverse vortex induced by grooves can lead to the secondary saltation of fly ash particles, which will significantly reduce particle deposition on fins. However, the longitudinal vortex generated by LVGs can result in the fly ash particles with saltation mode or suspension mode colliding with fin surface, which causes more particle deposition on fins. The recommended fin with three pairs of grooves and one pair of LVGs can enhance heat transfer by 12.92–16.63% with 21.75–30.72% flow resistance penalty and reduce the fouling rate by 2.4–23.7% for particle diameter under 20 μm. It can be considered as a promising heat transfer component for heat recovery in coal-fired power plants.

用于燃煤电厂中的余热回收的热交换器面临烟道气侧和粉煤灰结垢的传热效率低的问题。但是，传热增强结构总是会增加散热片上的结垢。需要有效的方法来改善热交换器的传热和防污性能。在本研究中，使用离散相模型与颗粒沉积和去除模型相结合，对增强型双H型翅片管的热工液压和防污性能进行了数值研究。研究了五种类型的具有不同沟槽布局和纵向涡流发生器（LVG）的双H型翅片管，以提高翅片的热工液压性能和防污性能。粒径的影响 讨论了烟气速度和增强结构的布置。发现由沟槽引起的横向涡流可导致飞灰颗粒的二次盐化，这将显着减少颗粒在鳍片上的沉积。但是，LVG产生的纵向涡流会导致盐分模式或悬浮模式的粉煤灰颗粒与鳍片表面发生碰撞，从而导致更多的颗粒沉积在鳍片上。推荐的带有三对凹槽和一对LVG的散热片可将热传递提高12.92–16.63％，流阻损失为21.75–30.72％，对于20μm以下的粒径，结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。发现由沟槽引起的横向涡流可导致飞灰颗粒的二次盐化，这将显着减少颗粒在鳍片上的沉积。但是，LVG产生的纵向涡流会导致盐分模式或悬浮模式的粉煤灰颗粒与鳍片表面发生碰撞，从而导致更多的颗粒沉积在鳍片上。推荐的带有三对凹槽和一对LVG的散热片可将热传递提高12.92–16.63％，流阻损失为21.75–30.72％，对于20μm以下的颗粒，结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。发现沟槽引起的横向涡流可导致粉煤灰颗粒的二次盐化，这将显着减少颗粒在鳍片上的沉积。但是，LVG产生的纵向涡流会导致盐分模式或悬浮模式的粉煤灰颗粒与鳍片表面发生碰撞，从而导致更多的颗粒沉积在鳍片上。推荐的带有三对凹槽和一对LVG的散热片可将热传递提高12.92–16.63％，流阻损失为21.75–30.72％，对于20μm以下的粒径，结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。LVG产生的纵向涡流可能导致盐分模式或悬浮模式的粉煤灰颗粒与鳍片表面碰撞，从而导致更多的颗粒沉积在鳍片上。推荐的带有三对凹槽和一对LVG的散热片可将热传递提高12.92–16.63％，流阻损失为21.75–30.72％，对于20μm以下的粒径，结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。LVG产生的纵向涡流可能导致盐分模式或悬浮模式的粉煤灰颗粒与鳍片表面碰撞，从而导致更多的颗粒沉积在鳍片上。推荐的带有三对凹槽和一对LVG的散热片可将热传递提高12.92–16.63％，流阻损失为21.75–30.72％，对于20μm以下的颗粒，结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。对于20μm以下的粒径，可减少72％的流动阻力损失，并降低结垢率2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。对于20μm以下的粒径，可降低72％的流动阻力，并使结垢率降低2.4–23.7％。它可以被认为是燃煤电厂热回收的有希望的传热组件。