Finned Heat Exchanger with Elliptical Finned Tube

Finned Heat Exchanger with Elliptical Finned Tube

A finned heat exchanger with elliptical finned tubes is a type of heat exchanger that uses elliptical tubes as the base tubes and is equipped with fins on the outer surface of the tubes to enhance heat transfer efficiency.

Structure

Heat exchange tubes: The heat exchange tubes are elliptical in cross - section. The inner wall of the tube may be constructed with protrusions, which can be spirally extended along the length direction of the heat exchange tube, or set at at least one end of the long axis of the heat exchange tube, and the cross - section of the protrusion extends along the circumferential direction of the inner wall of the heat exchange tube. The shape of the protrusion can be serrated.

Fins: There are multiple fins evenly spaced. Each fin is provided with multiple elliptical through - holes, and the heat exchange tubes are respectively inserted into the overlapping through - holes of each fin. The fins may include multiple heat dissipation units, and each heat dissipation unit is provided with heat dissipation ribs on both sides of the through - hole. The heat dissipation ribs are arch - shaped and hollow, and are provided with heat dissipation holes.

Manifold tubes: Usually, there are two manifold tubes, which are arranged in parallel at intervals. Multiple heat exchange tubes are respectively arranged in parallel at intervals to form two columns, and the same ends of the heat exchange tubes in one column extend into one manifold tube, and the same ends of the heat exchange tubes in the other column extend into the other manifold tube.

Working principle

When the hot medium (such as steam, hot water, etc.) flows inside the elliptical finned tube, the heat is transferred to the fins through the tube wall. The temperature of the hot medium is higher than that of the surrounding air. According to the principle of heat conduction, the heat will be transferred from the high - temperature fin surface to the low - temperature air. At the same time, the air flows over the finned tube surface under the action of the fan, creating convection heat transfer between the fins and the air, so as to realize the heat transfer process and heat the air.

Advantages

High heat transfer efficiency: The elliptical tube has a longer heat transfer perimeter under the same cross - sectional area, resulting in a larger heat transfer area. At the same time, the special shape of the elliptical tube can enhance the turbulence degree of the air on the wind side, improve the overall heat transfer effect, and increase the heat transfer coefficient between fluids.

Low flow resistance: The shape of the elliptical tube can delay the separation point of the separated flow around the tube, reduce the pressure drop outside the tube, and has a smaller air - side resistance than the circular tube. For the flow inside the tube, the equivalent diameter of the pipeline decreases, which is beneficial to heat transfer.

Compact structure: The elliptical tube is easier to achieve a compact arrangement, which can reduce the overall volume of the heat exchanger and the floor area.

Long service life: The rectangular steel fins commonly used in elliptical finned tubes have high strength, and the base tube is not easy to freeze and crack in winter, with a long service life.