Mechanism of Heat Transfer Enhancement in the Core Flow of a Tube and Its Numerical Simulation

ABSTRACT

The principle of heat transfer enhancement in the core flow of a tube has been proposed, in this paper, to make fluid temperature uniform in the core region of a tube and decrease flow resistance, which is different from heat transfer enhancement in the boundary flow of a tube. Two new models, representing heat transfer enhancement in the laminar and turbulent tube flow, have been established and numerically analyzed. Theoretical and numerical results indicate that heat transfer enhanced components designed according to the principle proposed in this paper will be benefit for increasing convective heat transfer coefficient, reducing flow resistance and raising the PEC value of a heat transfer enhanced tube. The presented principle, therefore, may help developing new type of heat transfer unit and designing heat exchanger with high heat transfer coefficient and low flow resistance.