This technology pertains to an H-type finned tube, specifically focusing on an axially penetrating H-type finned tube and its heat exchange tube bundle, applicable in various heat exchange and heating equipment across industries such as power, petroleum, chemical engineering, refrigeration, and metallurgy.

 

 

With the continuous rapid development of Chinas economy, issues related to energy supply shortages are becoming increasingly prominent, making energy conservation, emission reduction, and consumption reduction inevitable requirements for the countrys economic and social development. Heat exchangers, as important components of industrial processes in fields such as power, petroleum, chemical engineering, refrigeration, metallurgy, and even aerospace/rocketry, hold significant importance for safe and efficient operation. Among various heat exchange equipment, increasing the heat transfer area through fins is a common method to enhance heat transfer efficiency.

 

 

H-type finned tubes, also known as H-type fins or ribbed tubes, are named for their frontal shape resembling the letter "H." They are formed by symmetrically welding two steel plates with arcs onto a bare tube. Research and practice have shown that H-type finned tubes can significantly increase the heat transfer area, enlarge the cross-section of flue gas flow, reduce flue gas velocity, and decrease ash accumulation and wear. However, despite their good resistance to ash accumulation and wear, in the presence of ash-laden gas flow, due to the viscous effect of the fluid itself and the presence of adverse pressure gradients, flow separation inevitably occurs, forming a vortex stagnation zone on the lee side of the finned tube. This leads to continuous ash accumulation on the lee side, affecting the heat transfer efficiency of the finned tube and the safe and efficient operation of the heat exchanger.

 

 

The technology proposes an elliptical H-type finned tube. While the elliptical tube does reduce flow resistance compared to a circular tube, it does not disrupt the vortex stagnation zone due to minimal structural changes, thus providing limited improvement in ash accumulation. Various suggestions include installing certain longitudinal vortex generators to enhance heat transfer. However, compared to this, existing longitudinal vortex generators lack sufficient height perpendicular to the fins, leading to decreased heat transfer and ash accumulation resistance when the distance between fins is large. H-type finned tubes achieve heat exchange on discontinuous surfaces through various deformations of the outer edge of conventional H-type finned tubes. Although this structure can effectively increase the finning ratio and reduce fin spacing, the wear on the outer edge of the fins becomes more severe under high-speed ash-laden airflow, reducing the lifespan of the finned tubes.

 

 

To address the problems in the prior art, this technology aims to provide an axially penetrating H-type finned tube and its heat exchange tube bundle. By adding guide vanes to reduce flow separation and decrease the area of the vortex stagnation zone, ash accumulation on the lee side of the H-type finned tube is reduced, improving the operation of the heat exchanger.

 

 

The technology describes the current problems and challenges and proposes a structural optimization solution by adding guide vanes to the H-type finned tube. This design aims to reduce flow separation and the area of the vortex stagnation zone, thereby reducing ash accumulation and improving the operational efficiency and safety of the heat exchanger.

 

The technology offers a new design for H-type finned tubes used in industrial heat exchange equipment. Through structural improvements, it effectively addresses the issue of ash accumulation, presenting significant practical application value.