An inner liquid-distributing hood type condensing heat exchange tube

Abstract

The invention discloses an internal liquid-dividing hood-type condensed heat-exchanging pipe which can improve condensed phase change heat exchanging efficiency and belongs to the technical field of forced heat transfer. The condensed heat-exchanging pipe is formed by arranging an internal liquid-dividing hood with a microporous or seam structure inside a common external heat-exchanging pipe; condensed liquid formed in the heat-exchanging process flows through the micropore or the seam and is pumped and sucked into the liquid-dividing hood in time under the action of a liquid surface tension,so that the gas phase is separated from the liquid phase; the condensed liquid flows in the internal liquid-dividing hood and is drained out of the heat-exchanging pipe through the internal liquid-dividing hood; and steam is kept to flow in a clearance between the external heat-exchanging pipe and the internal liquid-dividing hood, so that the inner wall of the external heat-exchanging pipe contacts the steam to the maximum extent and a thin liquid film is formed on the inner wall surface of the external heat-exchanging pipe, and thus the condensed heat-exchanging coefficient is improved. Thetechnical problem that the heat transfer is deteriorated because a thick liquid film is formed in the direction of the pipe length in the condensed heat transfer process is fundamentally overcome; the internal liquid-dividing hood-type condensed heat-exchanging pipe is not affected by weight, so that the condensed heat transfer coefficient can be obviously improved on the ground and in a microgravity environment.

Description

technical field [0001] The invention belongs to the technical field of heat transfer enhancement, and relates to an internal liquid-distributing hood type condensation heat exchange tube for improving the thermal efficiency of condensation phase transformation in the tube. Background technique [0002] Condensing phase change heat exchangers (ie condensers) are widely used in refrigeration, air conditioning, power generation, petrochemical and other fields due to the high efficiency of phase change heat transfer. In some applications, such as using a low-grade heat source to drive the ORC cycle, it is necessary to reduce the temperature and pressure in the condenser in the Rankine cycle as much as possible, so that the condenser is in a small temperature difference (the temperature difference between the organic working medium in the tube and the air outside the tube or cooling water is small) Driven to work, resulting in an increase in heat transfer area and investment cost...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to change the separation of flow pattern and heat transfer in the traditional enhanced heat transfer method, solve the key problem that the thick liquid film is formed along the tube length direction in the condensation heat transfer, which makes the heat transfer worse, and provides a method different from the current one. The state-of-the-art internal liquid-distributing hood-type condensation heat exchange tube is based on the new idea of ​​regulating the condensation heat transfer flow pattern to improve the complete condensation heat transfer flow and heat transfer performance. It can start from the physical process of condensation, Starting from flow pattern control, fundamentally and greatly improve the efficiency of condensation phase change heat transfer

Images