Experimental study of heat transfer intensification under vibration condition

Experimental and theoretical models for enhancement of heat transfer from a tube with rings rotating on the external surface were investigated. The rings were rotated on acting vibration forces (hula-hoop phenomenon). The working fluid flowing into the tube was water. The Reynolds number ranged from 800 to 2000. The amplitude range of the parameters of vibration was 0.1 mm to 1 mm, and the frequency range was 10 to 120 Hz. On the basis of a dimensionless analysis, a mathematical model for the heat-transfer process was developed. It was shown that the mean heat transfer coefficient became higher as the velocity of vibration increased. The experimental results were in good agreement with the theoretical model.