RESEARCH ON HEAT TRANSFER AND FLOW CHARACTERISTICS OF CORRUGATED TUBES

摘要

Pointing at the special characteristics of flow field in corrugated tubes, a numerical simulation was performed d by using the RNG κ-ε turbulence model for three-dimensional fluid and the boundary condition of constant wall temperature in the tubes. The characteristics of turbulent flow and heat transfer in corrugated tubes of the diameter 16mm and the length 740mm were studied, with water at constant temperature as the medium and in different conditions of the velocity of flow at 0.5m/s, 0.8 m/s, 1.2 m/s. The temperature, velocity distribution, pressure value, turbulence intensity and the Nu number at different sections for fully developed fluid were obtained, which were compared with the results of smooth tubes. The numerical results showed that the quantity of heat transfer increased with the increase of the velocity of flow and the effect of turbulent enhanced heat transfer strengthened. It was found that the corrugated tubes can significantly enhance the heat transfer under the same diameter condition.