Streamline constant-amplitude parabolic corrugated fin for elliptical tube and fin heat exchanger

Abstract

Disclosed is a streamline constant-amplitude parabolic corrugated fin for an elliptical tube and fin heat exchanger. According to the direction of streamlines, from an air inlet to an air outlet, streamline parabolic convex corrugations 4 and streamline parabolic concave corrugations 5 with alternate convexes and concaves are made on a fin 1 by continuous stamping. Corrugation area edges (8) are both streamlined; before stamping, a center surface O-O of a front fin (a flat sheet) is determined with stream function values. All of the corrugations are the same in amplitude which is 0.1-0.9 times the spacing of fins. The streamlines allow no reflow to occur to the tail, which the fin 1 corresponds to, of a flat fin side passage of the tube and fin heat exchanger along the tube axial center section. Round tubes can be arranged in line or in a crossing manner. Convex corrugations 4 or concave corrugations 5 are symmetrically distributed around longitudinal and transverse center lines of tube holes 2. When fluid flows by the streamline constant-amplitude parabolic corrugated fin, part of the fluid flows in streamline passages formed by the convex corrugations 4 and the concave corrugations 5, flow resistance is reduced, and heat exchange capability of the fin is improved.

Description

technical field [0001] The invention relates to fins of an elliptical tube-tube-fin heat exchanger, in particular to a streamlined equal-amplitude parabolic corrugated fin of an elliptical tube-tube-fin heat exchanger. Background technique [0002] Tube-fin heat exchangers are widely used, and the total energy consumption is large, so it is very important to enhance the heat transfer characteristics of this type of heat exchanger. The thermal resistance of this type of heat exchanger is mainly concentrated on the fin side, so the energy consumption is also mainly consumed on the fin side. Generally, the working medium flowing in the tube of this type of heat exchanger is liquid, and the gas flowing on the fin side outside the tube is mostly air or other mixed gas. In order to reduce the thermal resistance on the gas side, installing fins on the outside of the tube can increase the heat transfer area and achieve the purpose of reducing thermal resistance. Thermal resistance...

AI Technical Summary

Problems solved by technology

[0003] Elliptical tube-and-fin heat exchangers have certain streamline characteristics compared with circular tubes due to their tube geometry, but when the tube size becomes larger or the flow rate increases, its streamlines become worse, and the flow of the fluid passing through the elliptical tube The detachment causes a large flow pressure loss, and forms a recirculation zone at the end of the oval tube that is not conducive to heat transfer

Existing fins do not improve fluid flow through the fin sides

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