A Straight Fin Tube with Bended Fins Condensing Heat Exchanger

Abstract

A forced convection fin tube condensing heat exchanger for supplying heat includes a shell, burner and fin tubes bundle. The burner is at the top of the shell, circular fin tubes bundle installed around the burner tightly, circularly and coaxially. The flue channel which is formed by the shell and a row of fin tubes bundle is below the burner. The flue flows along the flue channel to flue outlet. There are front and rear water manifolds at the two ends of the fin tubes. Water baffles inside the rear water manifold divide the rear water manifold into water inlet and outlet areas. The water enters the small portion of circular fin tubes bundle from water inlet area, through the front water manifold, back to the water outlet area via the main portion of the circular fin tubes bundle. The use of bended fin tube to improves efficiency.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a national stage application and claims priority to PCT / CN2013 / 083871, filed on Sep. 21, 2013, which claims priority to CN 201210353552.1, filed on Sep. 21, 2012, the disclosures of which are incorporated herein by reference in their entireties.FIELD OF THE INVENTION[0002]This invention relates generally to equipment in the heating industry field. More particularly, the invention is related to a forced convection straight fin tube condensing heat exchanger for supplying heat.BACKGROUND OF THE INVENTION[0003]As far back as the Middle East oil crisis in the in 20th century, to save the energy, the high efficient condensing boiler was developed in Europe. The outstanding feature of the boiler is that the efficiency is 10% higher than the conventional boiler. Abundant water vapor in the flue is condensed and releases the latent heat of vaporization because the flue temperature can be decreased to below the dew point. This ...

AI Technical Summary

Benefits of technology

The present invention pertains to a heat exchanger that uses forced convection to transfer heat between flue gas and water. The heat exchanger includes a shell, burner, fin tubes, water inlet, water outlet, flue outlet, and a connector between the burner and air / gas mixture. A set of fin tubes is installed around the burner tightly and coaxially. The flue channel is formed by the shell and a row of fin tubes below the burner. The fins on the external of the heat exchanger tubes increase the heat transfer surface area, improving heat exchange efficiency and making the heat exchanger smaller for a given heat exchange capacity. An air pre-heater can also be added to increase efficiency.

Problems solved by technology

The conventional boiler has very high flue temperature because of the limitation of the structure.

However, condensing boiler can not only use sensible heat in the flue but also the latent heat because of the low flue temperature.

It decreases the heat exchanging efficiency.

The heat exchanger is not designed to absorb the sensible and latent heat when the water vapor condensing, and there is no condensate.

The life the condensing boiler will be shortened significantly if the carbon steel or cast iron is used because the boiler generates a lot of acid condensing water.

It is a proven technology to make cast aluminum heat exchanger, but the capacity is limited.

It is very difficult to make the big cast aluminum parts.

Typically, the bigger the cast, the higher the mold cost, the more complex manufacturing process and the higher scrap rate.

Because there are a lot of components involved in the manufacture of heat exchangers, manufacturing many sizes of heat exchangers is not good practice for mass production.

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