Augmentation of Thermal Energy Transportation by an Oscillatory Flow in Grooved Ducts

This paper deals with heat transportation by oscillatory flow in grooved ducts. The heat transportation rate, work rate, heat transportation efficiency and variances of fluid particles and heat were analyzed with the computer code FLUENT. The frequency and amplitude of the oscillatory flow was 0.05 Hz and 45 mm. The internal diameters of the contraction section and the expansion section were 6 and 12 mm respectively and the length of the contraction section was fixed to be 10 mm with the length of groove varying from 0 to 40 mm. We found : (1) Heat transportation rate reached about 4.5 times as large as that of smooth round pipe at the groove length of around 10-15 mm. (2) Heat transportation efficiency increased to about 6.4 times that of smooth pipe at the groove length of 20 mm. (3) The dispersion of fluid particles caused the augmentation of the heat transportation of grooved ducts with 40 mm≥groove length≥5 mm. (4) The grooved ducts with the groove length of 10-15 mm had the maximum value of the variance of fluid particles which accounted for their high heat transportation rates.