Elliptical tube H-shaped fin heat exchanger for waste heat recovery

Abstract

The invention discloses an elliptical tube H-shaped fin heat exchanger for waste heat recovery. The elliptical tube H-shaped fin heat exchanger comprises an elliptical heat exchange tube, a plurality of groups of H-shaped fins and a heat exchanger surface, wherein the H-shaped fins are sleeved on the surface of the heat exchange tube; the heat exchanger surface consists of non-uniform triangular small wings, which are elliptically arranged, on the surfaces of the H-shaped fins around the elliptical heat exchange tube. When dusty flue gas flows through the surfaces of the H-shaped fins, the small wings disturb the fluid to enhance the heat exchange on the tube wall and the downstream side, and meanwhile, the deposition of particles on the tube wall is reduced; the pressure drop can be reduced by the elliptical tube while the particle adhesion is reduced. A plurality of longitudinal vortexes are arranged in a non-uniform manner; at the front and rear edges of the wing, the size of the small wings and the windward attack angle are larger; on the middle parts of the H-shaped fins, the size of the small wings and the attack angle are smaller; by using the device, the heat exchange surface in different flow states can be enhanced respectively, the heat exchange of the fins are effectively enhanced, the pressure drop is reduced, and the deposition of dust particles in the flue gas on the heat exchange surface is reduced, so that the heat exchanger can operate efficiently for a long time in the dusty flue gas.

Description

technical field [0001] The invention relates to a heat exchanger, in particular to an elliptical tube H-shaped fin heat exchanger suitable for waste heat recovery in industrial and power plant boiler economizers in the field of industrial low-temperature waste heat recovery. Background technique [0002] During the operation of industrial boilers and power plant boilers, a large amount of medium and low temperature flue gas will be generated, and the flue gas is usually discharged directly into the ambient air. Higher exhaust gas temperature will not only cause a large waste of waste heat resources, but also bring environmental pollution question. In order to reduce the exhaust gas temperature of the boiler and improve the heat utilization efficiency, an economizer is usually arranged in the tail flue of the boiler to reduce the temperature of the flue gas and recover part of the heat. The working fluid inside the economizer tube is water, and the outside of the tube is dus...

AI Technical Summary

Problems solved by technology

At present, the heat exchanger structure adopted in the industry is a round tube with straight fins. The windward area of ​​the round tube is large, the pressure drop loss and the dust accumulation in the wake area are serious, and the convective heat transfer coefficient of the straight fin is not high; Commonly used corrugated fins and slotted fins have high resistance, and are easy to accumulate dust and scale, so they are not suitable for flue gas environments; the longitudinal vortex generators reported in the literature have low resistance, but a single arrangement cannot meet the large heat transfer requirements

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