Single-phase media hydrodynamics and heat transfer in heat exchangers with twisted profile tubes

Abstract

A profiled heat exchanger tube is the one in which some features have been incorporated into the tube geometry for heat transfer enhancement. They offer a perspective method of steam turbine shell-and-tube heat exchangers improvement. Twisted profile tubes (TPT) are widely used in power engineering. This paper presents some results of experimental and theoretical research of hydrodynamics and heat transfer in TPTs. It is revealed that the heat transfer coefficient for water flow in a TPT increases up to 80% compared to that of a plain tube. With a rise of media Reynolds number, the heat transfer rate in a TPT decreases in comparison to that of a plain tube, but for air flow in a TPT the heat transfer coefficients ratio does not depend on the Reynolds number value. Water flow hydraulic losses in TPTs increase from 15 to 100% depending on the tube profile parameters. © 2014 WIT Press.